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Updated manual
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manual.md
@ -113,26 +113,28 @@ GLM.
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Core GLM features can be included using individual headers to allow faster user program compilations.
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Core GLM features can be included using individual headers to allow faster user program compilations.
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* <glm/vec2.hpp>: vec2, bvec2, dvec2, ivec2 and uvec2
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```cpp
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* <glm/vec3.hpp>: vec3, bvec3, dvec3, ivec3 and uvec3
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#include <glm/vec2.hpp> // vec2, bvec2, dvec2, ivec2 and uvec2
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* <glm/vec4.hpp>: vec4, bvec4, dvec4, ivec4 and uvec4
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#include <glm/vec3.hpp> // vec3, bvec3, dvec3, ivec3 and uvec3
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* <glm/mat2x2.hpp>: mat2, dmat2
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#include <glm/vec4.hpp> // vec4, bvec4, dvec4, ivec4 and uvec4
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* <glm/mat2x3.hpp>: mat2x3, dmat2x3
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#include <glm/mat2x2.hpp> // mat2, dmat2
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* <glm/mat2x4.hpp>: mat2x4, dmat2x4
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#include <glm/mat2x3.hpp> // mat2x3, dmat2x3
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* <glm/mat3x2.hpp>: mat3x2, dmat3x2
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#include <glm/mat2x4.hpp> // mat2x4, dmat2x4
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* <glm/mat3x3.hpp>: mat3, dmat3
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#include <glm/mat3x2.hpp> // mat3x2, dmat3x2
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* <glm/mat3x4.hpp>: mat3x4, dmat2
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#include <glm/mat3x3.hpp> // mat3, dmat3
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* <glm/mat4x2.hpp>: mat4x2, dmat4x2
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#include <glm/mat3x4.hpp> // mat3x4, dmat2
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* <glm/mat4x3.hpp>: mat4x3, dmat4x3
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#include <glm/mat4x2.hpp> // mat4x2, dmat4x2
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* <glm/mat4x4.hpp>: mat4, dmat4
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#include <glm/mat4x3.hpp> // mat4x3, dmat4x3
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* <glm/common.hpp>: all the GLSL common functions
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#include <glm/mat4x4.hpp> // mat4, dmat4
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* <glm/exponential.hpp>: all the GLSL exponential functions
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#include <glm/common.hpp> // all the GLSL common functions
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* <glm/geometry.hpp>: all the GLSL geometry functions
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#include <glm/exponential.hpp> // all the GLSL exponential functions
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* <glm/integer.hpp>: all the GLSL integer functions
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#include <glm/geometry.hpp> // all the GLSL geometry functions
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* <glm/matrix.hpp>: all the GLSL matrix functions
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#include <glm/integer.hpp> // all the GLSL integer functions
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* <glm/packing.hpp>: all the GLSL packing functions
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#include <glm/matrix.hpp> // all the GLSL matrix functions
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* <glm/trigonometric.hpp>: all the GLSL trigonometric functions
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#include <glm/packing.hpp> // all the GLSL packing functions
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* <glm/vector\_relational.hpp>: all the GLSL vector relational functions
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#include <glm/trigonometric.hpp> // all the GLSL trigonometric functions
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#include <glm/vector\_relational.hpp> // all the GLSL vector relational functions
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```
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### 1.2. Faster program compilation
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### 1.2. Faster program compilation
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@ -140,8 +142,7 @@ GLM is a header only library that makes a heavy usage of C++ templates.
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This design may significantly increase the compile time for files that use GLM. Hence, it is important to limit GLM inclusion to header and source files that actually use it. Likewise, GLM extensions should be
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This design may significantly increase the compile time for files that use GLM. Hence, it is important to limit GLM inclusion to header and source files that actually use it. Likewise, GLM extensions should be
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included only in program sources using them.
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included only in program sources using them.
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To further help compilation time, GLM 0.9.5 introduced
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To further help compilation time, GLM 0.9.5 introduced <glm/fwd.hpp> that provides forward declarations of GLM types.
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<glm/fwd.hpp> that provides forward declarations of GLM types.
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```cpp
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```cpp
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// Header file
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// Header file
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@ -298,66 +299,46 @@ functions so that the programmer must convert a swizzle operators to a
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vector type or call the () operator on a swizzle objects to pass it to
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vector type or call the () operator on a swizzle objects to pass it to
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another C++ functions.
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another C++ functions.
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---------------------------------------------------------------------------
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```cpp
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\#define GLM\_FORCE\_SWIZZLE
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#define GLM_FORCE_SWIZZLE
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#include <glm/glm.hpp>
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\#include <glm/glm.hpp>
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void foo()
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void foo()
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{
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{
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glm::vec4 Color(1.0f, 0.5f, 0.0f, 1.0f);
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> glm::vec4 Color(1.0f, 0.5f, 0.0f, 1.0f);
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...
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>
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> …
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// Generates compiler errors. Color.rgba is not a vector type.
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// Generates compiler errors. Color.rgba is not a vector type.
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glm::vec4 ClampedA = glm::clamp(Color.rgba, 0.f, 1.f); // ERROR
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> glm::vec4 ClampedA = glm::clamp(Color.rgba, 0.f, 1.f); // ERROR
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// We need to cast the swizzle operator into glm::vec4
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// We need to cast the swizzle operator into glm::vec4
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// With by using a constructor
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// With by using a constructor
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glm::vec4 ClampedB = glm::clamp(glm::vec4(Color.rgba), 0.f, 1.f); // OK
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> glm::vec4 ClampedB = glm::clamp(glm::vec4(Color.rgba), 0.f, 1.f); // OK
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// Or by using the () operator
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// Or by using the () operator
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glm::vec4 ClampedC = glm::clamp(Color.rgba(), 0.f, 1.f); // OK
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> glm::vec4 ClampedC = glm::clamp(Color.rgba(), 0.f, 1.f); // OK
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...
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>
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> …
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}
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}
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---------------------------------------------------------------------------
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```
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---------------------------------------------------------------------------
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3. Preprocessor options {#preprocessor-options .HeadingA}
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## 3. Preprocessor options
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=======================
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3.1. Default precision {#default-precision .HeadingB}
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### 3.1. Default precision
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----------------------
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In C++, it is not possible to implement GLSL default precision (GLSL
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In C++, it is not possible to implement GLSL default precision (GLSL 4.10 specification section 4.5.3) using GLSL syntax.
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4.10 specification section 4.5.3) using GLSL syntax.
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------------------------
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```cpp
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precision mediump int;
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precision mediump int;
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precision highp float;
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precision highp float;
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------------------------
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```
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------------------------
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To use the default precision functionality, GLM provides some defines
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To use the default precision functionality, GLM provides some defines that need to add before any include of glm.hpp:
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that need to add before any include of glm.hpp:
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----------------------------------------
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```cpp
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\#define GLM\_PRECISION\_MEDIUMP\_INT;
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#define GLM_PRECISION_MEDIUMP_INT
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#define GLM_PRECISION_HIGHP_FLOAT
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\#define GLM\_PRECISION\_HIGHP\_FLOAT;
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#include <glm/glm.hpp>
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```
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\#include <glm/glm.hpp>
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----------------------------------------
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----------------------------------------
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Available defines for floating point types (glm::vec\*, glm::mat\*):
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Available defines for floating point types (glm::vec\*, glm::mat\*):
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@ -374,53 +355,36 @@ GLM\_PRECISION\_HIGHP\_DOUBLE: High precision (default)
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Available defines for signed integer types (glm::ivec\*):
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Available defines for signed integer types (glm::ivec\*):
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GLM\_PRECISION\_LOWP\_INT: Low precision
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GLM\_PRECISION\_LOWP\_INT: Low precision
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GLM\_PRECISION\_MEDIUMP\_INT: Medium precision
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GLM\_PRECISION\_MEDIUMP\_INT: Medium precision
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GLM\_PRECISION\_HIGHP\_INT: High precision (default)
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GLM\_PRECISION\_HIGHP\_INT: High precision (default)
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Available defines for unsigned integer types (glm::uvec\*):
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Available defines for unsigned integer types (glm::uvec\*):
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GLM\_PRECISION\_LOWP\_UINT: Low precision
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GLM\_PRECISION\_LOWP\_UINT: Low precision
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GLM\_PRECISION\_MEDIUMP\_UINT: Medium precision
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GLM\_PRECISION\_MEDIUMP\_UINT: Medium precision
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GLM\_PRECISION\_HIGHP\_UINT: High precision (default)
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GLM\_PRECISION\_HIGHP\_UINT: High precision (default)
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3.2. Compile-time message system {#compile-time-message-system .HeadingB}
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### 3.2. Compile-time message system {#compile-time-message-system .HeadingB}
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--------------------------------
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GLM includes a notification system which can display some information at
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GLM includes a notification system which can display some information at build time:
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build time:
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- Platform: Windows, Linux, Native Client, QNX, etc.
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* Platform: Windows, Linux, Native Client, QNX, etc.
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* Compiler: Visual C++, Clang, GCC, ICC, etc.
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* Build model: 32bits or 64 bits
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* C++ version : C++98, C++11, MS extensions, etc.
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* Architecture: x86, SSE, AVX, etc.
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* Included extensions
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* etc.
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- Compiler: Visual C++, Clang, GCC, ICC, etc.
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This system is disabled by default. To enable this system, define GLM\_FORCE\_MESSAGES before any inclusion of <glm/glm.hpp>. The messages are generated only by compiler supporting \#program message and
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- Build model: 32bits or 64 bits
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- C++ version : C++98, C++11, MS extensions, etc.
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- Architecture: x86, SSE, AVX, etc.
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- Included extensions
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- etc.
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This system is disabled by default. To enable this system, define
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GLM\_FORCE\_MESSAGES before any inclusion of <glm/glm.hpp>. The
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messages are generated only by compiler supporting \#program message and
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only once per project build.
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only once per project build.
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-------------------------------
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```cpp
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\#define GLM\_FORCE\_MESSAGES
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#define GLM_FORCE_MESSAGES
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#include <glm/glm.hpp>
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```
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\#include <glm/glm.hpp>
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### 3.3. C++ language detection
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-------------------------------
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-------------------------------
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3.3. C++ language detection {#c-language-detection .HeadingB}
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---------------------------
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GLM will automatically take advantage of compilers’ language extensions
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GLM will automatically take advantage of compilers’ language extensions
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when enabled. To increase cross platform compatibility and to avoid
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when enabled. To increase cross platform compatibility and to avoid
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@ -428,128 +392,96 @@ compiler extensions, a programmer can define GLM\_FORCE\_CXX98 before
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any inclusion of <glm/glm.hpp> to restrict the language feature
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any inclusion of <glm/glm.hpp> to restrict the language feature
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set C++98:
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set C++98:
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-------------------------------
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```cpp
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\#define GLM\_FORCE\_CXX98
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#define GLM_FORCE_CXX98
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#include <glm/glm.hpp>
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\#include <glm/glm.hpp>
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```
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-------------------------------
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-------------------------------
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For C++11 and C++14, equivalent defines are available:
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For C++11 and C++14, equivalent defines are available:
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GLM\_FORCE\_CXX11, GLM\_FORCE\_CXX14.
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GLM\_FORCE\_CXX11, GLM\_FORCE\_CXX14.
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-------------------------------
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```cpp
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\#define GLM\_FORCE\_CXX11
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#define GLM_FORCE_CXX11
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#include <glm/glm.hpp>
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\#include <glm/glm.hpp>
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// If the compiler doesn’t support C++11, compiler errors will happen.
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-------------------------------
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```
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-------------------------------
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GLM\_FORCE\_CXX14 overrides GLM\_FORCE\_CXX11 and GLM\_FORCE\_CXX11
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GLM\_FORCE\_CXX14 overrides GLM\_FORCE\_CXX11 and GLM\_FORCE\_CXX11
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overrides GLM\_FORCE\_CXX98 defines.
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overrides GLM\_FORCE\_CXX98 defines.
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3.4. SIMD support {#simd-support .HeadingB}
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### 3.4. SIMD support
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-----------------
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GLM provides some SIMD optimizations based on [compiler
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GLM provides some SIMD optimizations based on [compiler intrinsics](https://msdn.microsoft.com/en-us/library/26td21ds.aspx).
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intrinsics](https://msdn.microsoft.com/en-us/library/26td21ds.aspx).
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These optimizations will be automatically thanks to compiler arguments.
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These optimizations will be automatically thanks to compiler arguments.
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For example, if a program is compiled with Visual Studio using
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For example, if a program is compiled with Visual Studio using
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/arch:AVX, GLM will detect this argument and generate code using AVX
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/arch:AVX, GLM will detect this argument and generate code using AVX
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instructions automatically when available.
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instructions automatically when available.
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It’s possible to avoid the instruction set detection by forcing the use
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It’s possible to avoid the instruction set detection by forcing the use of a specific instruction set with one of the fallowing define:
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of a specific instruction set with one of the fallowing define:
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GLM\_FORCE\_SSE2, GLM\_FORCE\_SSE3, GLM\_FORCE\_SSSE3, GLM\_FORCE\_SSE41, GLM\_FORCE\_SSE42, GLM\_FORCE\_AVX, GLM\_FORCE\_AVX2 or GLM\_FORCE\_AVX512.
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GLM\_FORCE\_SSE2, GLM\_FORCE\_SSE3, GLM\_FORCE\_SSSE3,
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GLM\_FORCE\_SSE41, GLM\_FORCE\_SSE42, GLM\_FORCE\_AVX, GLM\_FORCE\_AVX2
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or GLM\_FORCE\_AVX512.
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The use of intrinsic functions by GLM implementation can be avoided
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The use of intrinsic functions by GLM implementation can be avoided
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using the define GLM\_FORCE\_PURE before any inclusion of GLM headers.
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using the define GLM\_FORCE\_PURE before any inclusion of GLM headers.
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+--------------------------------------------------------------------------+
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```cpp
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| \#define GLM\_FORCE\_PURE |
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#define GLM_FORCE_PURE
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#include <glm/glm.hpp>
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| \#include <glm/glm.hpp>\ |
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| \ |
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| // GLM code will be compiled using pure C++ code |
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+==========================================================================+
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+--------------------------------------------------------------------------+
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+--------------------------------------------------------------------------+
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// GLM code will be compiled using pure C++ code without any intrinsics
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| \#define GLM\_FORCE\_AVX2 |
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```
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| \#include <glm/glm.hpp>\ |
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```cpp
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| \ |
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#define GLM_FORCE_AVX2
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| // If the compiler doesn’t support AVX2 instrinsics,\ |
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#include <glm/glm.hpp>
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| // compiler errors will happen. |
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+==========================================================================+
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// If the compiler doesn’t support AVX2 instrinsics, compiler errors will happen.
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+--------------------------------------------------------------------------+
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```
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Additionally, GLM provides a low level SIMD API in glm/simd directory
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Additionally, GLM provides a low level SIMD API in glm/simd directory
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for users who are really interested in writing fast algorithms.
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for users who are really interested in writing fast algorithms.
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3.5. Force inline {#force-inline .HeadingB}
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### 3.5. Force inline
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-----------------
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To push further the software performance, a programmer can define
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To push further the software performance, a programmer can define
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GLM\_FORCE\_INLINE before any inclusion of <glm/glm.hpp> to force
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GLM\_FORCE\_INLINE before any inclusion of <glm/glm.hpp> to force
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the compiler to inline GLM code.
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the compiler to inline GLM code.
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-------------------------------
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```cpp
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\#define GLM\_FORCE\_INLINE
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#define GLM_FORCE_INLINE
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#include <glm/glm.hpp>
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```
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\#include <glm/glm.hpp>
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### 3.6. Vector and matrix static size
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-------------------------------
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-------------------------------
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3.6. Vector and matrix static size {#vector-and-matrix-static-size .HeadingB}
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GLSL supports the member function .length() for all vector and matrix types.
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----------------------------------
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GLSL supports the member function .length() for all vector and matrix
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```cpp
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types.
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#include <glm/glm.hpp>
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-------------------------------
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\#include <glm/glm.hpp>
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void foo(vec4 const & v)
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void foo(vec4 const & v)
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{
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{
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int Length = v.length();
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> int Length = v.length();
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...
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>
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> …
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}
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}
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-------------------------------
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```
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-------------------------------
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This function returns a int however this function typically interacts
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This function returns a int however this function typically interacts with STL size\_t based code. GLM provides GLM\_FORCE\_SIZE\_T\_LENGTH pre-processor option so that member functions length() return a size\_t.
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with STL size\_t based code. GLM provides GLM\_FORCE\_SIZE\_T\_LENGTH
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pre-processor option so that member functions length() return a size\_t.
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Additionally, GLM defines the type glm::length\_t to identify length()
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Additionally, GLM defines the type glm::length\_t to identify length() returned type, independently from GLM\_FORCE\_SIZE\_T\_LENGTH.
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returned type, independently from GLM\_FORCE\_SIZE\_T\_LENGTH.
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--------------------------------------
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```cpp
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\#define GLM\_FORCE\_SIZE\_T\_LENGTH
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#define GLM_FORCE_SIZE_T_LENGTH
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#include <glm/glm.hpp>
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\#include <glm/glm.hpp>
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void foo(vec4 const & v)
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void foo(vec4 const & v)
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{
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{
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glm::size_t Length = v.length();
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> glm::size\_t Length = v.length();
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...
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>
|
|
||||||
> …
|
|
||||||
|
|
||||||
}
|
}
|
||||||
--------------------------------------
|
```
|
||||||
--------------------------------------
|
|
||||||
|
|
||||||
3.7. Disabling default constructor initialization {#disabling-default-constructor-initialization .HeadingB}
|
### 3.7. Disabling default constructor initialization
|
||||||
-------------------------------------------------
|
|
||||||
|
|
||||||
By default and following GLSL specifications, vector and matrix default
|
By default and following GLSL specifications, vector and matrix default
|
||||||
constructors initialize the components to zero. This is a reliable
|
constructors initialize the components to zero. This is a reliable
|
||||||
@ -560,232 +492,171 @@ or other GLM include.
|
|||||||
|
|
||||||
GLM default behavior:
|
GLM default behavior:
|
||||||
|
|
||||||
-------------------------------------------------
|
```cpp
|
||||||
\#include <glm/glm.hpp>
|
#include <glm/glm.hpp>
|
||||||
|
|
||||||
void foo()
|
void foo()
|
||||||
|
|
||||||
{
|
{
|
||||||
|
glm::vec4 v; // v is (0.0f, 0.0f, 0.0f, 0.0f)
|
||||||
> glm::vec4 v; // v is (0.0f, 0.0f, 0.0f, 0.0f)
|
...
|
||||||
>
|
|
||||||
> …
|
|
||||||
|
|
||||||
}
|
}
|
||||||
-------------------------------------------------
|
```
|
||||||
-------------------------------------------------
|
|
||||||
|
|
||||||
GLM behavior using GLM\_FORCE\_NO\_CTOR\_INIT:
|
GLM behavior using GLM\_FORCE\_NO\_CTOR\_INIT:
|
||||||
|
|
||||||
------------------------------------------
|
```cpp
|
||||||
\#define GLM\_FORCE\_NO\_CTOR\_INIT
|
#define GLM_FORCE_NO_CTOR_INIT
|
||||||
|
#include <glm/glm.hpp>
|
||||||
\#include <glm/glm.hpp>
|
|
||||||
|
|
||||||
void foo()
|
void foo()
|
||||||
|
|
||||||
{
|
{
|
||||||
|
glm::vec4 v; // v is fill with garbage
|
||||||
> glm::vec4 v; // v is fill with garbage
|
...
|
||||||
>
|
|
||||||
> …
|
|
||||||
|
|
||||||
}
|
}
|
||||||
------------------------------------------
|
```
|
||||||
------------------------------------------
|
|
||||||
|
|
||||||
Alternatively, GLM allows to explicitly not initialize a variable:
|
Alternatively, GLM allows to explicitly not initialize a variable:
|
||||||
|
|
||||||
-----------------------------------
|
```cpp
|
||||||
\#include <glm/glm.hpp>
|
#include <glm/glm.hpp>
|
||||||
|
|
||||||
void foo()
|
void foo()
|
||||||
|
|
||||||
{
|
{
|
||||||
|
glm::vec4 v(glm::uninitialize);
|
||||||
> glm::vec4 v(glm::uninitialize);
|
...
|
||||||
>
|
|
||||||
> …
|
|
||||||
|
|
||||||
}
|
}
|
||||||
-----------------------------------
|
```
|
||||||
-----------------------------------
|
|
||||||
|
|
||||||
3.8. Require explicit conversions {#require-explicit-conversions .HeadingB}
|
### 3.8. Require explicit conversions
|
||||||
---------------------------------
|
|
||||||
|
|
||||||
GLSL supports implicit conversions of vector and matrix types. For
|
GLSL supports implicit conversions of vector and matrix types. For example, an ivec4 can be implicitly converted into vec4.
|
||||||
example, an ivec4 can be implicitly converted into vec4.
|
|
||||||
|
|
||||||
Often, this behaviour is not desirable but following the spirit of the
|
Often, this behaviour is not desirable but following the spirit of the library, this behavior is supported in GLM. However, GLM 0.9.6 introduced the define GLM\_FORCE\_EXPLICIT\_CTOR to require explicit
|
||||||
library, this behavior is supported in GLM. However, GLM 0.9.6
|
|
||||||
introduced the define GLM\_FORCE\_EXPLICIT\_CTOR to require explicit
|
|
||||||
conversion for GLM types.
|
conversion for GLM types.
|
||||||
|
|
||||||
+--------------------------------------------------------------------------+
|
```cpp
|
||||||
| \#include <glm/glm.hpp> |
|
#include <glm/glm.hpp>
|
||||||
| |
|
|
||||||
| void foo() |
|
|
||||||
| |
|
|
||||||
| { |
|
|
||||||
| |
|
|
||||||
| > glm::ivec4 a;\ |
|
|
||||||
| > … |
|
|
||||||
| > |
|
|
||||||
| > glm::vec4 b(a); // Explicit conversion, OK\ |
|
|
||||||
| > glm::vec4 c = a; // Implicit conversion, OK |
|
|
||||||
| > |
|
|
||||||
| > … |
|
|
||||||
| |
|
|
||||||
| } |
|
|
||||||
+==========================================================================+
|
|
||||||
+--------------------------------------------------------------------------+
|
|
||||||
|
|
||||||
With GLM\_FORCE\_EXPLICIT\_CTOR define, implicit conversions are not
|
void foo()
|
||||||
allowed:
|
{
|
||||||
|
glm::ivec4 a;
|
||||||
|
...
|
||||||
|
|
||||||
+--------------------------------------------------------------------------+
|
glm::vec4 b(a); // Explicit conversion, OK
|
||||||
| \#define GLM\_FORCE\_EXPLICIT\_CTOR |
|
glm::vec4 c = a; // Implicit conversion, OK
|
||||||
| |
|
...
|
||||||
| \#include <glm/glm.hpp> |
|
}
|
||||||
| |
|
```
|
||||||
| void foo() |
|
|
||||||
| |
|
|
||||||
| { |
|
|
||||||
| |
|
|
||||||
| > glm::ivec4 a;\ |
|
|
||||||
| > … |
|
|
||||||
| > |
|
|
||||||
| > glm::vec4 b(a); // Explicit conversion, OK\ |
|
|
||||||
| > glm::vec4 c = a; // Implicit conversion, ERROR |
|
|
||||||
| > |
|
|
||||||
| > … |
|
|
||||||
| |
|
|
||||||
| } |
|
|
||||||
+==========================================================================+
|
|
||||||
+--------------------------------------------------------------------------+
|
|
||||||
|
|
||||||
3.9. Removing genType restriction {#removing-gentype-restriction .HeadingB}
|
With GLM\_FORCE\_EXPLICIT\_CTOR define, implicit conversions are not allowed:
|
||||||
---------------------------------
|
|
||||||
|
|
||||||
By default GLM only supports basic types as genType for vector, matrix
|
```cpp
|
||||||
and quaternion types:
|
#define GLM_FORCE_EXPLICIT_CTOR
|
||||||
|
#include <glm/glm.hpp>
|
||||||
|
|
||||||
--------------------------------------------
|
void foo()
|
||||||
\#include <glm/glm.hpp>
|
{
|
||||||
|
glm::ivec4 a;
|
||||||
|
{
|
||||||
|
glm::vec4 b(a); // Explicit conversion, OK
|
||||||
|
glm::vec4 c = a; // Implicit conversion, ERROR
|
||||||
|
...
|
||||||
|
}
|
||||||
|
```
|
||||||
|
|
||||||
typedef glm::tvec4<float> my\_fvec4;
|
### 3.9. Removing genType restriction
|
||||||
--------------------------------------------
|
|
||||||
--------------------------------------------
|
|
||||||
|
|
||||||
GLM 0.9.8 introduced GLM\_FORCE\_UNRESTRICTED\_GENTYPE define to relax
|
By default GLM only supports basic types as genType for vector, matrix and quaternion types:
|
||||||
this restriction:
|
|
||||||
|
|
||||||
+--------------------------------------------------------------------------+
|
```cpp
|
||||||
| \#define GLM\_FORCE\_UNRESTRICTED\_GENTYPE\ |
|
#include <glm/glm.hpp>
|
||||||
| \#include <glm/glm.hpp> |
|
|
||||||
| |
|
|
||||||
| \#include "half.hpp" // Define “half” class with equivalent behavior |
|
|
||||||
| than “float” |
|
|
||||||
| |
|
|
||||||
| typedef glm::tvec4<half> my\_hvec4; |
|
|
||||||
+==========================================================================+
|
|
||||||
+--------------------------------------------------------------------------+
|
|
||||||
|
|
||||||
However, defining GLM\_FORCE\_UNRESTRICTED\_GENTYPE is not compatible
|
typedef glm::tvec4<float> my_fvec4;
|
||||||
with GLM\_FORCE\_SWIZZLE and will generate a compilation error if both
|
```
|
||||||
are defined at the same time.
|
|
||||||
|
|
||||||
4. Stable extensions {#stable-extensions .HeadingA}
|
GLM 0.9.8 introduced GLM\_FORCE\_UNRESTRICTED\_GENTYPE define to relax this restriction:
|
||||||
====================
|
|
||||||
|
|
||||||
GLM extends the core GLSL feature set with extensions. These extensions
|
```cpp
|
||||||
include: quaternion, transformation, spline, matrix inverse, color
|
#define GLM_FORCE_UNRESTRICTED_GENTYPE
|
||||||
spaces, etc.
|
#include <glm/glm.hpp>
|
||||||
|
|
||||||
To include an extension, we only need to include the dedicated header
|
#include "half.hpp" // Define “half” class with equivalent behavior than “float”
|
||||||
file. Once included, the features are added to the GLM namespace.
|
|
||||||
|
|
||||||
---------------------------------------------------------
|
typedef glm::tvec4<half> my_hvec4;
|
||||||
\#include <glm/glm.hpp>
|
```
|
||||||
|
|
||||||
\#include <glm/gtc/matrix\_transform.hpp>
|
However, defining GLM\_FORCE\_UNRESTRICTED\_GENTYPE is not compatible with GLM\_FORCE\_SWIZZLE and will generate a compilation error if both are defined at the same time.
|
||||||
|
|
||||||
|
## 4. Stable extensions
|
||||||
|
|
||||||
|
GLM extends the core GLSL feature set with extensions. These extensions include: quaternion, transformation, spline, matrix inverse, color spaces, etc.
|
||||||
|
|
||||||
|
To include an extension, we only need to include the dedicated header file. Once included, the features are added to the GLM namespace.
|
||||||
|
|
||||||
|
```cpp
|
||||||
|
#include <glm/glm.hpp>
|
||||||
|
#include <glm/gtc/matrix_transform.hpp>
|
||||||
|
|
||||||
int foo()
|
int foo()
|
||||||
|
|
||||||
{
|
{
|
||||||
|
|
||||||
glm::vec4 Position = glm::vec4(glm:: vec3(0.0f), 1.0f);
|
glm::vec4 Position = glm::vec4(glm:: vec3(0.0f), 1.0f);
|
||||||
|
glm::mat4 Model = glm::translate(glm::mat4(1.0f), glm::vec3(1.0f));
|
||||||
|
|
||||||
glm::mat4 Model = glm::translate(
|
glm::vec4 Transformed = Model * Position;
|
||||||
|
...
|
||||||
> glm::mat4(1.0f), glm::vec3(1.0f));
|
|
||||||
|
|
||||||
glm::vec4 Transformed = Model \* Position;
|
|
||||||
|
|
||||||
…
|
|
||||||
|
|
||||||
return 0;
|
return 0;
|
||||||
|
|
||||||
}
|
}
|
||||||
---------------------------------------------------------
|
```
|
||||||
---------------------------------------------------------
|
|
||||||
|
|
||||||
When an extension is included, all the dependent core functionalities
|
When an extension is included, all the dependent core functionalities
|
||||||
and extensions will be included as well.
|
and extensions will be included as well.
|
||||||
|
|
||||||
4.1. GLM\_GTC\_bitfield {#glm_gtc_bitfield .HeadingB}
|
### 4.1. GLM_GTC_bitfield
|
||||||
-----------------------
|
|
||||||
|
|
||||||
Fast bitfield operations on scalar and vector variables.
|
Fast bitfield operations on scalar and vector variables.
|
||||||
|
|
||||||
<glm/gtc/bitfield.hpp> need to be included to use these features.
|
<glm/gtc/bitfield.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.2. GLM\_GTC\_color\_space {#glm_gtc_color_space .HeadingB}
|
### 4.2. GLM_GTC_color_space
|
||||||
---------------------------
|
|
||||||
|
|
||||||
Conversion between linear RGB to sRGB and sRGB to linear RGB.
|
Conversion between linear RGB to sRGB and sRGB to linear RGB.
|
||||||
|
|
||||||
<glm/gtc/color\_space.hpp> need to be included to use these
|
<glm/gtc/color\_space.hpp> need to be included to use these
|
||||||
features.
|
features.
|
||||||
|
|
||||||
4.3. GLM\_GTC\_constants {#glm_gtc_constants .HeadingB}
|
### 4.3. GLM\_GTC\_constants
|
||||||
------------------------
|
|
||||||
|
|
||||||
Provide a list of built-in constants.
|
Provide a list of built-in constants.
|
||||||
|
|
||||||
<glm/gtc/constants.hpp> need to be included to use these features.
|
<glm/gtc/constants.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.4. GLM\_GTC\_epsilon {#glm_gtc_epsilon .HeadingB}
|
### 4.4. GLM\_GTC\_epsilon
|
||||||
----------------------
|
|
||||||
|
|
||||||
Approximate equal and not equal comparisons with selectable epsilon.
|
Approximate equal and not equal comparisons with selectable epsilon.
|
||||||
|
|
||||||
<glm/gtc/epsilon.hpp> need to be included to use these features.
|
<glm/gtc/epsilon.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.5. GLM\_GTC\_functions {#glm_gtc_functions .HeadingB}
|
### 4.5. GLM\_GTC\_functions
|
||||||
------------------------
|
|
||||||
|
|
||||||
Useful functions.
|
Useful functions.
|
||||||
|
|
||||||
<glm/gtc/functions.hpp> need to be included to use these features.
|
<glm/gtc/functions.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.6. GLM\_GTC\_integer {#glm_gtc_integer .HeadingB}
|
### 4.6. GLM\_GTC\_integer
|
||||||
----------------------
|
|
||||||
|
|
||||||
Provide integer variants of GLM core functions.
|
Provide integer variants of GLM core functions.
|
||||||
|
|
||||||
<glm/gtc/integer.hpp> need to be included to use these features.
|
<glm/gtc/integer.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.7. GLM\_GTC\_matrix\_access {#glm_gtc_matrix_access .HeadingB}
|
### 4.7. GLM\_GTC\_matrix\_access
|
||||||
-----------------------------
|
|
||||||
|
|
||||||
Define functions to access rows or columns of a matrix easily.
|
Define functions to access rows or columns of a matrix easily.
|
||||||
|
|
||||||
<glm/gtc/matrix\_access.hpp> need to be included to use these
|
<glm/gtc/matrix\_access.hpp> need to be included to use these
|
||||||
features.
|
features.
|
||||||
|
|
||||||
4.8. GLM\_GTC\_matrix\_integer {#glm_gtc_matrix_integer .HeadingB}
|
### 4.8. GLM\_GTC\_matrix\_integer {#glm_gtc_matrix_integer .HeadingB}
|
||||||
------------------------------
|
------------------------------
|
||||||
|
|
||||||
Provide integer matrix types. Inverse and determinant functions are not
|
Provide integer matrix types. Inverse and determinant functions are not
|
||||||
@ -794,7 +665,7 @@ supported for these types.
|
|||||||
<glm/gtc/matrix\_integer.hpp> need to be included to use these
|
<glm/gtc/matrix\_integer.hpp> need to be included to use these
|
||||||
features.
|
features.
|
||||||
|
|
||||||
4.9. GLM\_GTC\_matrix\_inverse {#glm_gtc_matrix_inverse .HeadingB}
|
### 4.9. GLM\_GTC\_matrix\_inverse {#glm_gtc_matrix_inverse .HeadingB}
|
||||||
------------------------------
|
------------------------------
|
||||||
|
|
||||||
Define additional matrix inverting functions.
|
Define additional matrix inverting functions.
|
||||||
@ -802,7 +673,7 @@ Define additional matrix inverting functions.
|
|||||||
<glm/gtc/matrix\_inverse.hpp> need to be included to use these
|
<glm/gtc/matrix\_inverse.hpp> need to be included to use these
|
||||||
features.
|
features.
|
||||||
|
|
||||||
4.10. GLM\_GTC\_matrix\_transform {#glm_gtc_matrix_transform .HeadingB}
|
### 4.10. GLM\_GTC\_matrix\_transform {#glm_gtc_matrix_transform .HeadingB}
|
||||||
---------------------------------
|
---------------------------------
|
||||||
|
|
||||||
Define functions that generate common transformation matrices.
|
Define functions that generate common transformation matrices.
|
||||||
@ -817,7 +688,7 @@ layout of this eye space.
|
|||||||
<glm/gtc/matrix\_transform.hpp> need to be included to use these
|
<glm/gtc/matrix\_transform.hpp> need to be included to use these
|
||||||
features.
|
features.
|
||||||
|
|
||||||
4.11. GLM\_GTC\_noise {#glm_gtc_noise .HeadingB}
|
### 4.11. GLM\_GTC\_noise {#glm_gtc_noise .HeadingB}
|
||||||
---------------------
|
---------------------
|
||||||
|
|
||||||
Define 2D, 3D and 4D procedural noise functions.
|
Define 2D, 3D and 4D procedural noise functions.
|
||||||
@ -872,7 +743,7 @@ height="2.6666666666666665in"}
|
|||||||
Figure 4.11.9: glm::perlin(glm::vec4(x / 16.f, y / 16.f,
|
Figure 4.11.9: glm::perlin(glm::vec4(x / 16.f, y / 16.f,
|
||||||
glm::vec2(0.5f)), glm::vec4(2.0f));
|
glm::vec2(0.5f)), glm::vec4(2.0f));
|
||||||
|
|
||||||
4.12. GLM\_GTC\_packing {#glm_gtc_packing .HeadingB}
|
### 4.12. GLM\_GTC\_packing {#glm_gtc_packing .HeadingB}
|
||||||
-----------------------
|
-----------------------
|
||||||
|
|
||||||
Convert scalar and vector types to packed formats. This extension can
|
Convert scalar and vector types to packed formats. This extension can
|
||||||
@ -883,7 +754,7 @@ will be perform loselessly.
|
|||||||
|
|
||||||
<glm/gtc/packing.hpp> need to be included to use these features.
|
<glm/gtc/packing.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.13. GLM\_GTC\_quaternion {#glm_gtc_quaternion .HeadingB}
|
### 4.13. GLM\_GTC\_quaternion {#glm_gtc_quaternion .HeadingB}
|
||||||
--------------------------
|
--------------------------
|
||||||
|
|
||||||
Define a quaternion type and several quaternion operations.
|
Define a quaternion type and several quaternion operations.
|
||||||
@ -891,7 +762,7 @@ Define a quaternion type and several quaternion operations.
|
|||||||
<glm/gtc/quaternion.hpp> need to be included to use these
|
<glm/gtc/quaternion.hpp> need to be included to use these
|
||||||
features.
|
features.
|
||||||
|
|
||||||
4.14. GLM\_GTC\_random {#glm_gtc_random .HeadingB}
|
### 4.14. GLM\_GTC\_random {#glm_gtc_random .HeadingB}
|
||||||
----------------------
|
----------------------
|
||||||
|
|
||||||
Generate random number from various distribution methods.
|
Generate random number from various distribution methods.
|
||||||
@ -925,7 +796,7 @@ height="2.7395833333333335in"}
|
|||||||
|
|
||||||
Figure 4.14.6: glm::vec4(glm::gaussRand(glm::vec3(0), glm::vec3(1)), 1);
|
Figure 4.14.6: glm::vec4(glm::gaussRand(glm::vec3(0), glm::vec3(1)), 1);
|
||||||
|
|
||||||
4.15. GLM\_GTC\_reciprocal {#glm_gtc_reciprocal .HeadingB}
|
### 4.15. GLM\_GTC\_reciprocal {#glm_gtc_reciprocal .HeadingB}
|
||||||
--------------------------
|
--------------------------
|
||||||
|
|
||||||
Provide hyperbolic functions: secant, cosecant, cotangent, etc.
|
Provide hyperbolic functions: secant, cosecant, cotangent, etc.
|
||||||
@ -933,7 +804,7 @@ Provide hyperbolic functions: secant, cosecant, cotangent, etc.
|
|||||||
<glm/gtc/reciprocal.hpp> need to be included to use these
|
<glm/gtc/reciprocal.hpp> need to be included to use these
|
||||||
functionalities.
|
functionalities.
|
||||||
|
|
||||||
4.16. GLM\_GTC\_round {#glm_gtc_round .HeadingB}
|
### 4.16. GLM\_GTC\_round {#glm_gtc_round .HeadingB}
|
||||||
---------------------
|
---------------------
|
||||||
|
|
||||||
Rounding operation on power of two and multiple values.
|
Rounding operation on power of two and multiple values.
|
||||||
@ -941,7 +812,7 @@ Rounding operation on power of two and multiple values.
|
|||||||
<glm/gtc/round.hpp> need to be included to use these
|
<glm/gtc/round.hpp> need to be included to use these
|
||||||
functionalities.
|
functionalities.
|
||||||
|
|
||||||
4.17. GLM\_GTC\_type\_aligned {#glm_gtc_type_aligned .HeadingB}
|
### 4.17. GLM\_GTC\_type\_aligned {#glm_gtc_type_aligned .HeadingB}
|
||||||
-----------------------------
|
-----------------------------
|
||||||
|
|
||||||
Aligned vector types.
|
Aligned vector types.
|
||||||
@ -949,7 +820,7 @@ Aligned vector types.
|
|||||||
<glm/gtc/type\_aligned.hpp> need to be included to use these
|
<glm/gtc/type\_aligned.hpp> need to be included to use these
|
||||||
functionalities.
|
functionalities.
|
||||||
|
|
||||||
4.18. GLM\_GTC\_type\_precision {#glm_gtc_type_precision .HeadingB}
|
### 4.18. GLM\_GTC\_type\_precision {#glm_gtc_type_precision .HeadingB}
|
||||||
-------------------------------
|
-------------------------------
|
||||||
|
|
||||||
Add vector and matrix types with defined precisions. Eg, i8vec4: vector
|
Add vector and matrix types with defined precisions. Eg, i8vec4: vector
|
||||||
@ -1043,7 +914,7 @@ GLM\_PRECISION\_HIGHP\_FLOAT64: High precision (default)
|
|||||||
<glm/gtc/type\_precision.hpp> need to be included to use these
|
<glm/gtc/type\_precision.hpp> need to be included to use these
|
||||||
functionalities.
|
functionalities.
|
||||||
|
|
||||||
4.19. GLM\_GTC\_type\_ptr {#glm_gtc_type_ptr .HeadingB}
|
### 4.19. GLM\_GTC\_type\_ptr {#glm_gtc_type_ptr .HeadingB}
|
||||||
-------------------------
|
-------------------------
|
||||||
|
|
||||||
Handle the interaction between pointers and vector, matrix types.
|
Handle the interaction between pointers and vector, matrix types.
|
||||||
@ -1109,7 +980,7 @@ form of notification. *
|
|||||||
|
|
||||||
<glm/gtc/type\_ptr.hpp> need to be included to use these features.
|
<glm/gtc/type\_ptr.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.20. GLM\_GTC\_ulp {#glm_gtc_ulp .HeadingB}
|
### 4.20. GLM\_GTC\_ulp {#glm_gtc_ulp .HeadingB}
|
||||||
-------------------
|
-------------------
|
||||||
|
|
||||||
Allow the measurement of the accuracy of a function against a reference
|
Allow the measurement of the accuracy of a function against a reference
|
||||||
@ -1119,18 +990,16 @@ results in
|
|||||||
|
|
||||||
<glm/gtc/ulp.hpp> need to be included to use these features.
|
<glm/gtc/ulp.hpp> need to be included to use these features.
|
||||||
|
|
||||||
4.21. GLM\_GTC\_vec1 {#glm_gtc_vec1 .HeadingB}
|
### 4.21. GLM\_GTC\_vec1 {#glm_gtc_vec1 .HeadingB}
|
||||||
--------------------
|
--------------------
|
||||||
|
|
||||||
Add \*vec1 types.
|
Add \*vec1 types.
|
||||||
|
|
||||||
<glm/gtc/vec1.hpp> need to be included to use these features.
|
<glm/gtc/vec1.hpp> need to be included to use these features.
|
||||||
|
|
||||||
5. OpenGL interoperability {#opengl-interoperability .HeadingA}
|
## 5. OpenGL interoperability
|
||||||
==========================
|
|
||||||
|
|
||||||
5.1. GLM replacements for deprecated OpenGL functions {#glm-replacements-for-deprecated-opengl-functions .HeadingB}
|
### 5.1. GLM replacements for deprecated OpenGL functions
|
||||||
------------------------------------------------------
|
|
||||||
|
|
||||||
OpenGL 3.1 specification has deprecated some features that have been
|
OpenGL 3.1 specification has deprecated some features that have been
|
||||||
removed from OpenGL 3.2 core profile specification. GLM provides some
|
removed from OpenGL 3.2 core profile specification. GLM provides some
|
||||||
|
Loading…
Reference in New Issue
Block a user