glm/test/external/gli/texture.hpp

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2016-11-18 22:16:29 +00:00
/// @brief Include to use generic textures which can represent any texture target but they don't have target specific built-in caches making accesses slower.
/// @file gli/texture.hpp
#pragma once
#include "image.hpp"
#include "target.hpp"
#include "levels.hpp"
#include <array>
namespace gli
{
/// Genetic texture class. It can support any target.
class texture
{
public:
typedef size_t size_type;
typedef gli::target target_type;
typedef gli::format format_type;
typedef gli::swizzles swizzles_type;
typedef storage_linear storage_type;
typedef storage_type::data_type data_type;
typedef storage_type::extent_type extent_type;
/// Create an empty texture instance
texture();
/// Create a texture object and allocate a texture storage for it
/// @param Target Type/Shape of the texture storage_linear
/// @param Format Texel format
/// @param Extent Size of the texture: width, height and depth.
/// @param Layers Number of one-dimensional or two-dimensional images of identical size and format
/// @param Faces 6 for cube map textures otherwise 1.
/// @param Levels Number of images in the texture mipmap chain.
/// @param Swizzles A mechanism to swizzle the components of a texture before they are applied according to the texture environment.
texture(
target_type Target,
format_type Format,
extent_type const& Extent,
size_type Layers,
size_type Faces,
size_type Levels,
swizzles_type const& Swizzles = swizzles_type(SWIZZLE_RED, SWIZZLE_GREEN, SWIZZLE_BLUE, SWIZZLE_ALPHA));
/// Create a texture object by sharing an existing texture storage_type from another texture instance.
/// This texture object is effectively a texture view where the layer, the face and the level allows identifying
/// a specific subset of the texture storage_linear source.
/// This texture object is effectively a texture view where the target and format can be reinterpreted
/// with a different compatible texture target and texture format.
texture(
texture const& Texture,
target_type Target,
format_type Format,
size_type BaseLayer, size_type MaxLayer,
size_type BaseFace, size_type MaxFace,
size_type BaseLevel, size_type MaxLevel,
swizzles_type const& Swizzles = swizzles_type(SWIZZLE_RED, SWIZZLE_GREEN, SWIZZLE_BLUE, SWIZZLE_ALPHA));
/// Create a texture object by sharing an existing texture storage_type from another texture instance.
/// This texture object is effectively a texture view where the target and format can be reinterpreted
/// with a different compatible texture target and texture format.
texture(
texture const& Texture,
target_type Target,
format_type Format,
swizzles_type const& Swizzles = swizzles_type(SWIZZLE_RED, SWIZZLE_GREEN, SWIZZLE_BLUE, SWIZZLE_ALPHA));
virtual ~texture(){}
/// Return whether the texture instance is empty, no storage_type or description have been assigned to the instance.
bool empty() const;
/// Return the target of a texture instance.
target_type target() const{return this->Target;}
/// Return the texture instance format
format_type format() const;
swizzles_type swizzles() const;
/// Return the base layer of the texture instance, effectively a memory offset in the actual texture storage_type to identify where to start reading the layers.
size_type base_layer() const;
/// Return the max layer of the texture instance, effectively a memory offset to the beginning of the last layer in the actual texture storage_type that the texture instance can access.
size_type max_layer() const;
/// Return max_layer() - base_layer() + 1
size_type layers() const;
/// Return the base face of the texture instance, effectively a memory offset in the actual texture storage_type to identify where to start reading the faces.
size_type base_face() const;
/// Return the max face of the texture instance, effectively a memory offset to the beginning of the last face in the actual texture storage_type that the texture instance can access.
size_type max_face() const;
/// Return max_face() - base_face() + 1
size_type faces() const;
/// Return the base level of the texture instance, effectively a memory offset in the actual texture storage_type to identify where to start reading the levels.
size_type base_level() const;
/// Return the max level of the texture instance, effectively a memory offset to the beginning of the last level in the actual texture storage_type that the texture instance can access.
size_type max_level() const;
/// Return max_level() - base_level() + 1.
size_type levels() const;
/// Return the size of a texture instance: width, height and depth.
extent_type extent(size_type Level = 0) const;
/// Return the memory size of a texture instance storage_type in bytes.
size_type size() const;
/// Return the number of blocks contained in a texture instance storage_type.
/// genType size must match the block size conresponding to the texture format.
template <typename genType>
size_type size() const;
/// Return the memory size of a specific level identified by Level.
size_type size(size_type Level) const;
/// Return the memory size of a specific level identified by Level.
/// genType size must match the block size conresponding to the texture format.
template <typename gen_type>
size_type size(size_type Level) const;
/// Return a pointer to the beginning of the texture instance data.
void* data();
/// Return a pointer of type genType which size must match the texture format block size
template <typename gen_type>
gen_type* data();
/// Return a pointer to the beginning of the texture instance data.
void const* data() const;
/// Return a pointer of type genType which size must match the texture format block size
template <typename gen_type>
gen_type const* data() const;
/// Return a pointer to the beginning of the texture instance data.
void* data(size_type Layer, size_type Face, size_type Level);
/// Return a pointer to the beginning of the texture instance data.
void const* const data(size_type Layer, size_type Face, size_type Level) const;
/// Return a pointer of type genType which size must match the texture format block size
template <typename gen_type>
gen_type* data(size_type Layer, size_type Face, size_type Level);
/// Return a pointer of type genType which size must match the texture format block size
template <typename gen_type>
gen_type const* const data(size_type Layer, size_type Face, size_type Level) const;
/// Clear the entire texture storage_linear with zeros
void clear();
/// Clear the entire texture storage_linear with Texel which type must match the texture storage_linear format block size
/// If the type of gen_type doesn't match the type of the texture format, no conversion is performed and the data will be reinterpreted as if is was of the texture format.
template <typename gen_type>
void clear(gen_type const& Texel);
/// Clear a specific image of a texture.
template <typename gen_type>
void clear(size_type Layer, size_type Face, size_type Level, gen_type const& BlockData);
/// Clear a subset of a specific image of a texture.
template <typename gen_type>
void clear(size_type Layer, size_type Face, size_type Level, extent_type const& TexelOffset, extent_type const& TexelExtent, gen_type const& BlockData);
/// Copy a specific image of a texture
void copy(
texture const& TextureSrc,
size_t LayerSrc, size_t FaceSrc, size_t LevelSrc,
size_t LayerDst, size_t FaceDst, size_t LevelDst);
/// Copy a subset of a specific image of a texture
void copy(
texture const& TextureSrc,
size_t LayerSrc, size_t FaceSrc, size_t LevelSrc, extent_type const& OffsetSrc,
size_t LayerDst, size_t FaceDst, size_t LevelDst, extent_type const& OffsetDst,
extent_type const& Extent);
/// Reorder the component in texture memory.
template <typename gen_type>
void swizzle(gli::swizzles const& Swizzles);
/// Fetch a texel from a texture. The texture format must be uncompressed.
template <typename gen_type>
gen_type load(extent_type const & TexelCoord, size_type Layer, size_type Face, size_type Level) const;
/// Write a texel to a texture. The texture format must be uncompressed.
template <typename gen_type>
void store(extent_type const& TexelCoord, size_type Layer, size_type Face, size_type Level, gen_type const& Texel);
protected:
std::shared_ptr<storage_type> Storage;
target_type Target;
format_type Format;
size_type BaseLayer;
size_type MaxLayer;
size_type BaseFace;
size_type MaxFace;
size_type BaseLevel;
size_type MaxLevel;
swizzles_type Swizzles;
// Pre compute at texture instance creation some information for faster access to texels
struct cache
{
public:
enum ctor
{
DEFAULT
};
explicit cache(ctor)
{}
cache
(
storage_type& Storage,
format_type Format,
size_type BaseLayer, size_type Layers,
size_type BaseFace, size_type MaxFace,
size_type BaseLevel, size_type MaxLevel
)
: Faces(MaxFace - BaseFace + 1)
, Levels(MaxLevel - BaseLevel + 1)
{
GLI_ASSERT(static_cast<size_t>(gli::levels(Storage.extent(0))) < this->ImageMemorySize.size());
this->BaseAddresses.resize(Layers * this->Faces * this->Levels);
for(size_type Layer = 0; Layer < Layers; ++Layer)
for(size_type Face = 0; Face < this->Faces; ++Face)
for(size_type Level = 0; Level < this->Levels; ++Level)
{
size_type const Index = index_cache(Layer, Face, Level);
this->BaseAddresses[Index] = Storage.data() + Storage.base_offset(
BaseLayer + Layer, BaseFace + Face, BaseLevel + Level);
}
for(size_type Level = 0; Level < this->Levels; ++Level)
{
extent_type const& SrcExtent = Storage.extent(BaseLevel + Level);
extent_type const& DstExtent = SrcExtent * block_extent(Format) / Storage.block_extent();
this->ImageExtent[Level] = glm::max(DstExtent, extent_type(1));
this->ImageMemorySize[Level] = Storage.level_size(BaseLevel + Level);
}
this->GlobalMemorySize = Storage.layer_size(BaseFace, MaxFace, BaseLevel, MaxLevel) * Layers;
}
// Base addresses of each images of a texture.
data_type* get_base_address(size_type Layer, size_type Face, size_type Level) const
{
return this->BaseAddresses[index_cache(Layer, Face, Level)];
}
// In texels
extent_type get_extent(size_type Level) const
{
return this->ImageExtent[Level];
};
// In bytes
size_type get_memory_size(size_type Level) const
{
return this->ImageMemorySize[Level];
};
// In bytes
size_type get_memory_size() const
{
return this->GlobalMemorySize;
};
private:
size_type index_cache(size_type Layer, size_type Face, size_type Level) const
{
return ((Layer * this->Faces) + Face) * this->Levels + Level;
}
size_type Faces;
size_type Levels;
std::vector<data_type*> BaseAddresses;
std::array<extent_type, 16> ImageExtent;
std::array<size_type, 16> ImageMemorySize;
size_type GlobalMemorySize;
} Cache;
};
}//namespace gli
#include "./core/texture.inl"