UI: Perf: Batch icons drawcalls together.

For this we use a new shader that gets it's data from a uniform array.
Vertex shader position the vertices using these data.

Using glUniform is way faster than using imm for that matter.

Like BLF rendering, UI icons are always (as far as I know) non occluded and
displayed above everything else. They also does not overlap with texts so
they can be batched at the same time.

5 files changed, 66 insertions, 0 deletions

diff --git a/source/blender/gpu/CMakeLists.txt b/source/blender/gpu/CMakeLists.txt
index f0e5b0842fc..b52817c68a8 100644
--- a/source/blender/gpu/CMakeLists.txt
+++ b/source/blender/gpu/CMakeLists.txt
@@ -141,6 +141,7 @@ data_to_c_simple(shaders/gpu_shader_2D_smooth_color_vert.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_2D_smooth_color_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_2D_image_vert.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_2D_image_rect_vert.glsl SRC)
+data_to_c_simple(shaders/gpu_shader_2D_image_multi_rect_vert.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_linear_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_shuffle_color_frag.glsl SRC)
@@ -148,6 +149,7 @@ data_to_c_simple(shaders/gpu_shader_image_mask_uniform_color_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_modulate_alpha_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_alpha_color_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_color_frag.glsl SRC)
+data_to_c_simple(shaders/gpu_shader_image_varying_color_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_depth_linear_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_depth_copy_frag.glsl SRC)
 data_to_c_simple(shaders/gpu_shader_image_interlace_frag.glsl SRC)
diff --git a/source/blender/gpu/GPU_shader.h b/source/blender/gpu/GPU_shader.h
index 1a1ec120d28..5041d524f18 100644
--- a/source/blender/gpu/GPU_shader.h
+++ b/source/blender/gpu/GPU_shader.h
@@ -116,6 +116,7 @@ typedef enum GPUBuiltinShader {
 	GPU_SHADER_2D_IMAGE_ALPHA_COLOR,
 	GPU_SHADER_2D_IMAGE_ALPHA,
 	GPU_SHADER_2D_IMAGE_RECT_COLOR,
+	GPU_SHADER_2D_IMAGE_MULTI_RECT_COLOR,
 	GPU_SHADER_2D_CHECKER,
 	GPU_SHADER_2D_DIAG_STRIPES,
 	/* for simple 3D drawing */
diff --git a/source/blender/gpu/intern/gpu_shader.c b/source/blender/gpu/intern/gpu_shader.c
index ad6331befce..55184418284 100644
--- a/source/blender/gpu/intern/gpu_shader.c
+++ b/source/blender/gpu/intern/gpu_shader.c
@@ -66,12 +66,14 @@ extern char datatoc_gpu_shader_2D_smooth_color_vert_glsl[];
 extern char datatoc_gpu_shader_2D_smooth_color_frag_glsl[];
 extern char datatoc_gpu_shader_2D_image_vert_glsl[];
 extern char datatoc_gpu_shader_2D_image_rect_vert_glsl[];
+extern char datatoc_gpu_shader_2D_image_multi_rect_vert_glsl[];
 extern char datatoc_gpu_shader_2D_widget_base_vert_glsl[];
 
 extern char datatoc_gpu_shader_3D_image_vert_glsl[];
 extern char datatoc_gpu_shader_image_frag_glsl[];
 extern char datatoc_gpu_shader_image_linear_frag_glsl[];
 extern char datatoc_gpu_shader_image_color_frag_glsl[];
+extern char datatoc_gpu_shader_image_varying_color_frag_glsl[];
 extern char datatoc_gpu_shader_image_alpha_color_frag_glsl[];
 extern char datatoc_gpu_shader_image_shuffle_color_frag_glsl[];
 extern char datatoc_gpu_shader_image_interlace_frag_glsl[];
@@ -710,6 +712,8 @@ GPUShader *GPU_shader_get_builtin_shader(GPUBuiltinShader shader)
 		                                        datatoc_gpu_shader_image_shuffle_color_frag_glsl },
 		[GPU_SHADER_2D_IMAGE_RECT_COLOR] = { datatoc_gpu_shader_2D_image_rect_vert_glsl,
 		                                     datatoc_gpu_shader_image_color_frag_glsl },
+		[GPU_SHADER_2D_IMAGE_MULTI_RECT_COLOR] = { datatoc_gpu_shader_2D_image_multi_rect_vert_glsl,
+		                                           datatoc_gpu_shader_image_varying_color_frag_glsl },
 
 		[GPU_SHADER_3D_UNIFORM_COLOR] = { datatoc_gpu_shader_3D_vert_glsl, datatoc_gpu_shader_uniform_color_frag_glsl },
 		[GPU_SHADER_3D_UNIFORM_COLOR_U32] = { datatoc_gpu_shader_3D_vert_glsl, datatoc_gpu_shader_uniform_color_frag_glsl },
diff --git a/source/blender/gpu/shaders/gpu_shader_2D_image_multi_rect_vert.glsl b/source/blender/gpu/shaders/gpu_shader_2D_image_multi_rect_vert.glsl
new file mode 100644
index 00000000000..9fdf8ececc5
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_2D_image_multi_rect_vert.glsl
@@ -0,0 +1,48 @@
+/**
+ * Simple shader that just draw multiple icons at the specified locations
+ * does not need any vertex input (producing less call to immBegin/End)
+ **/
+
+/* Same as ICON_DRAW_CACHE_SIZE */
+#define MAX_CALLS 16
+
+uniform vec4 calls_data[MAX_CALLS * 3];
+
+out vec2 texCoord_interp;
+flat out vec4 finalColor;
+
+void main()
+{
+	/* Rendering 2 triangle per icon. */
+	int i = gl_VertexID / 6;
+	int v = gl_VertexID % 6;
+
+	vec4 pos = calls_data[i*3];
+	vec4 tex = calls_data[i*3+1];
+	finalColor = calls_data[i*3+2];
+
+	/* TODO Remove this */
+	if (v == 2) v = 4;
+	else if (v == 3) v = 0;
+	else if (v == 5) v = 2;
+
+	if (v == 0) {
+		pos.xy = pos.xw;
+		tex.xy = tex.xw;
+	}
+	else if (v == 1) {
+		pos.xy = pos.xz;
+		tex.xy = tex.xz;
+	}
+	else if (v == 2) {
+		pos.xy = pos.yw;
+		tex.xy = tex.yw;
+	}
+	else {
+		pos.xy = pos.yz;
+		tex.xy = tex.yz;
+	}
+
+	gl_Position = vec4(pos.xy, 0.0f, 1.0f);
+	texCoord_interp = tex.xy;
+}
diff --git a/source/blender/gpu/shaders/gpu_shader_image_varying_color_frag.glsl b/source/blender/gpu/shaders/gpu_shader_image_varying_color_frag.glsl
new file mode 100644
index 00000000000..37686092700
--- /dev/null
+++ b/source/blender/gpu/shaders/gpu_shader_image_varying_color_frag.glsl
@@ -0,0 +1,11 @@
+
+in vec2 texCoord_interp;
+flat in vec4 finalColor;
+out vec4 fragColor;
+
+uniform sampler2D image;
+
+void main()
+{
+	fragColor = texture(image, texCoord_interp) * finalColor;
+}