Add angle changing

examples/basic.cpp

@@ -1,5 +1,7 @@
 #include <sprstk/sprstk.h>
 
+#include <cstdlib>
+
 namespace
 {
 
@@ -9,7 +11,7 @@ void init(sprstk* instance, void* userdata)
 
   for (int i = 0; i < 28; i++)
   {
-    pal.colors[i] = 0x7F4F0040;
+    pal.colors[i] = 0x7F3F0040;
   }
 
   for (int i = 28; i < 32; i++)
@@ -20,13 +22,16 @@ void init(sprstk* instance, void* userdata)
   sprstk_set_palette(instance, 0, &pal);
 }
 
-void update(sprstk* instance, float dt, void* userdata)
+void update(sprstk* instance, float dt, float* userdata)
 {
-  for (int i = 0; i < 16; i++)
+  *userdata += dt / 2;
+  sprstk_set_angle(instance, *userdata);
+
+  for (int i = -512; i < 512; i++)
   {
-    for (int j = 15; j >= 0; j--)
+    for (int j = -512; j < 512; j++)
     {
-      sprstk_put(instance, i - 8, j - 8, i + j + 1, 0);
+      sprstk_put(instance, i, j, 31, 0);
     }
   }
 }
@@ -35,7 +40,8 @@ void update(sprstk* instance, float dt, void* userdata)
 
 int main()
 {
-  sprstk* instance = sprstk_new({.init = init, .update = update}, nullptr);
+  float data = 0;
+  sprstk* instance = sprstk_new({.init = init, .update = (sprstk_update_fn)update}, &data);
 
   sprstk_run(instance);
 

include/sprstk/sprstk.h

@@ -35,6 +35,8 @@ void sprstk_putz(sprstk* instance, int x, int y, unsigned int layers, unsigned i
 
 void sprstk_set_palette(sprstk* instance, unsigned int index, const sprstk_palette* palette);
 
+void sprstk_set_angle(sprstk* instance, float angle);
+
 #ifdef __cplusplus
 }
 #endif

src/sprstk.cpp

@@ -5,6 +5,8 @@
 
 #include <stdexcept>
 
+#include <cmath>
+
 const char* MESH_SHADER_CODE = R"(
 #version 460
 
@@ -19,6 +21,7 @@ layout (location = 0) out PerVertexData
 } v_out[];
 
 layout (location = 1) uniform vec3 screen_size_and_pixel_scale;
+layout (location = 2) uniform mat2 rotation_matrix;
 
 struct TileInfo
 {
@@ -56,22 +59,23 @@ void main()
   {
     positions[i] += stack_position;
     positions[i] *= screen_size_and_pixel_scale.zz;
-    positions[i] /= screen_size_and_pixel_scale.xy;
+    positions[i] /= vec2(min(screen_size_and_pixel_scale.x, screen_size_and_pixel_scale.y));
   }
 
   uint z_offset = bitfieldExtract(t_info.position, 25, 2);
 
   uint palette_lookup = bitfieldExtract(t_info.position, 27, 5);
   ColorInfo c_info = color_infos[palette_lookup];
-  float a = bitfieldExtract(c_info.color[int(ceil(gl_LocalInvocationID.x * (32.0 / layer_count)))], 0, 8);
+  float a = bitfieldExtract(c_info.color[gl_LocalInvocationID.x], 0, 8);
-  float b = bitfieldExtract(c_info.color[int(ceil(gl_LocalInvocationID.x * (32.0 / layer_count)))], 8, 8);
+  float b = bitfieldExtract(c_info.color[gl_LocalInvocationID.x], 8, 8);
-  float g = bitfieldExtract(c_info.color[int(ceil(gl_LocalInvocationID.x * (32.0 / layer_count)))], 16, 8);
+  float g = bitfieldExtract(c_info.color[gl_LocalInvocationID.x], 16, 8);
-  float r = bitfieldExtract(c_info.color[int(ceil(gl_LocalInvocationID.x * (32.0 / layer_count)))], 24, 8);
+  float r = bitfieldExtract(c_info.color[gl_LocalInvocationID.x], 24, 8);
 
   for (uint i = 4 * gl_LocalInvocationID.x; i < 4 * gl_LocalInvocationID.x + 4; i++)
   {
-    vec4 position = vec4(positions[i % 4], float(4 * gl_LocalInvocationID.x + z_offset) / 128, 1);
+    vec4 position = vec4(rotation_matrix * positions[i % 4], float(4 * gl_LocalInvocationID.x + z_offset) / 128, 1);
     position.y += 24 * position.z / screen_size_and_pixel_scale.z;
+    position.xy *= vec2(0.05);
     gl_MeshVerticesNV[i].gl_Position = position;
 
     v_out[i].color = vec4(r, g, b, a) / vec4(256, 256, 256, 256);
@@ -82,7 +86,7 @@ void main()
     gl_PrimitiveIndicesNV[i] = 4 * gl_LocalInvocationID.x + indices[i % 6];
   }
 
-  gl_PrimitiveCountNV = layer_count * 2;
+  gl_PrimitiveCountNV = layer_count * 2 + 2;
 }
 )";
 
@@ -157,19 +161,24 @@ public:
           int width, height;
           SDL_GetWindowSizeInPixels(sdl.window, &width, &height);
           glViewport(0, 0, width, height);
-          glProgramUniform3f(gl.program, 1, width, height, 32);
+          glProgramUniform3f(gl.program, 1, width, height, 8);
         }
       }
 
       uint64_t current_ticks = SDL_GetTicks();
-      float dt = (prev_ticks - current_ticks) / 1000.0f;
+      float dt = (current_ticks - prev_ticks) / 1000.0f;
+      prev_ticks = current_ticks;
 
       gl.tile_count = 0;
       callbacks.update(this, dt, userdata);
 
       glClearColor(0, 0, 0, 1);
       glClear(GL_COLOR_BUFFER_BIT);
-      glDrawMeshTasksNV(0, gl.tile_count);
+      int i;
+      for (i = 0; i < gl.tile_count; i += 65535)
+      {
+        glDrawMeshTasksNV(i, 65535);
+      }
 
       SDL_GL_SwapWindow(sdl.window);
     }
@@ -210,6 +219,15 @@ public:
     gl.color_info_map[index] = *palette;
   }
 
+  void set_angle(float angle)
+  {
+    const float arr[4] = {
+      cosf(angle), -sinf(angle),
+      sinf(angle),  cosf(angle)
+    };
+    glProgramUniformMatrix2fv(gl.program, 2, 1, false, arr);
+  }
+
 private:
   sprstk_callbacks callbacks;
   void* userdata;
@@ -331,7 +349,7 @@ private:
     int width, height;
     SDL_GetWindowSizeInPixels(sdl.window, &width, &height);
     glViewport(0, 0, width, height);
-    glProgramUniform3f(gl.program, 1, width, height, 32);
+    glProgramUniform3f(gl.program, 1, width, height, 8);
 
     glGenBuffers(1, &gl.tile_buffer);
     glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 0, gl.tile_buffer);
@@ -345,6 +363,9 @@ private:
     glNamedBufferStorage(gl.color_buffer, sizeof(sprstk_palette) * (1 << 5), nullptr, GL_MAP_WRITE_BIT | GL_MAP_COHERENT_BIT | GL_MAP_PERSISTENT_BIT);
 
     gl.color_info_map = (sprstk_palette*)glMapNamedBufferRange(gl.color_buffer, 0, sizeof(sprstk_palette) * (1 << 5), GL_MAP_WRITE_BIT | GL_MAP_COHERENT_BIT);
+
+    const float arr[4] = {1, 0, 0, 1};
+    glProgramUniformMatrix2fv(gl.program, 2, 1, false, arr);
   }
 
   void destroy_gl()
@@ -414,4 +435,9 @@ void sprstk_set_palette(sprstk* instance, unsigned int index, const sprstk_palet
   instance->set_palette(index, palette);
 }
 
+void sprstk_set_angle(sprstk* instance, float angle)
+{
+  instance->set_angle(angle);
+}
+
 }