DRW: DebugDraw: Port module to C++ and add GPU capabilities

This is a complete rewrite of the draw debug drawing module in C++.
It uses `GPUStorageBuf` to store the data to be drawn and use indirect
drawing. This makes it easier to do a mirror API for GPU shaders.

The C++ API class is exposed through `draw_debug.hh` and should be used
when possible in new code.

However, the debug drawing will not work for platform not yet supporting
`GPUStorageBuf`. Also keep in mind that this module must only be used
in debug build for performance and compatibility reasons.

1 files changed, 8 insertions, 0 deletions

diff --git a/source/blender/gpu/GPU_shader.h b/source/blender/gpu/GPU_shader.h
index c154f1adc8b..529a3da3ab9 100644
--- a/source/blender/gpu/GPU_shader.h
+++ b/source/blender/gpu/GPU_shader.h
@@ -148,11 +148,19 @@ typedef enum {
   GPU_NUM_UNIFORM_BLOCKS, /* Special value, denotes number of builtin uniforms block. */
 } GPUUniformBlockBuiltin;
 
+typedef enum {
+  GPU_STORAGE_BUFFER_DEBUG_VERTS = 0, /* drw_debug_verts_buf */
+  GPU_STORAGE_BUFFER_DEBUG_PRINT,     /* drw_debug_print_buf */
+
+  GPU_NUM_STORAGE_BUFFERS, /* Special value, denotes number of builtin buffer blocks. */
+} GPUStorageBufferBuiltin;
+
 void GPU_shader_set_srgb_uniform(GPUShader *shader);
 
 int GPU_shader_get_uniform(GPUShader *shader, const char *name);
 int GPU_shader_get_builtin_uniform(GPUShader *shader, int builtin);
 int GPU_shader_get_builtin_block(GPUShader *shader, int builtin);
+int GPU_shader_get_builtin_ssbo(GPUShader *shader, int builtin);
 /** DEPRECATED: Kept only because of Python GPU API. */
 int GPU_shader_get_uniform_block(GPUShader *shader, const char *name);
 int GPU_shader_get_ssbo(GPUShader *shader, const char *name);