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, 14 insertions, 0 deletions

diff --git a/source/blender/gpu/opengl/gl_shader_interface.cc b/source/blender/gpu/opengl/gl_shader_interface.cc
index 1b3ab2941a8..4623a14dab3 100644
--- a/source/blender/gpu/opengl/gl_shader_interface.cc
+++ b/source/blender/gpu/opengl/gl_shader_interface.cc
@@ -318,6 +318,13 @@ GLShaderInterface::GLShaderInterface(GLuint program)
     builtin_blocks_[u] = (block != nullptr) ? block->binding : -1;
   }
 
+  /* Builtin Storage Buffers */
+  for (int32_t u_int = 0; u_int < GPU_NUM_STORAGE_BUFFERS; u_int++) {
+    GPUStorageBufferBuiltin u = static_cast<GPUStorageBufferBuiltin>(u_int);
+    const ShaderInput *block = this->ssbo_get(builtin_storage_block_name(u));
+    builtin_buffers_[u] = (block != nullptr) ? block->binding : -1;
+  }
+
   MEM_freeN(uniforms_from_blocks);
 
   /* Resize name buffer to save some memory. */
@@ -481,6 +488,13 @@ GLShaderInterface::GLShaderInterface(GLuint program, const shader::ShaderCreateI
     builtin_blocks_[u] = (block != nullptr) ? block->binding : -1;
   }
 
+  /* Builtin Storage Buffers */
+  for (int32_t u_int = 0; u_int < GPU_NUM_STORAGE_BUFFERS; u_int++) {
+    GPUStorageBufferBuiltin u = static_cast<GPUStorageBufferBuiltin>(u_int);
+    const ShaderInput *block = this->ssbo_get(builtin_storage_block_name(u));
+    builtin_buffers_[u] = (block != nullptr) ? block->binding : -1;
+  }
+
   this->sort_inputs();
 
   // this->debug_print();