Add debug option --debug-gpumem to show GPU memory used in status bar.

Only used in ATIs and NVIDIAs. Used extensions are:

https://www.opengl.org/registry/specs/ATI/meminfo.txt
http://developer.download.nvidia.com/opengl/specs/

If you read the documentation, the numbers are not supposed to be exact
and also depend on the time when the call is made. The numbers can also
change quite quickly. It's only meant to give a rough measure of what is
going on.

2 files changed, 31 insertions, 0 deletions

diff --git a/source/blender/gpu/GPU_extensions.h b/source/blender/gpu/GPU_extensions.h
index 27a4396e5d8..f3927ba960b 100644
--- a/source/blender/gpu/GPU_extensions.h
+++ b/source/blender/gpu/GPU_extensions.h
@@ -71,6 +71,9 @@ int GPU_max_texture_size(void);
 int GPU_color_depth(void);
 void GPU_get_dfdy_factors(float fac[2]);
 
+bool GPU_mem_stats_supported(void);
+void GPU_mem_stats_get(int *totalmem, int *freemem);
+
 void GPU_code_generate_glsl_lib(void);
 
 /* GPU Types */
diff --git a/source/blender/gpu/intern/gpu_extensions.c b/source/blender/gpu/intern/gpu_extensions.c
index b095eab6952..54e3339eb29 100644
--- a/source/blender/gpu/intern/gpu_extensions.c
+++ b/source/blender/gpu/intern/gpu_extensions.c
@@ -2084,6 +2084,34 @@ void GPU_shader_free_builtin_shaders(void)
 	}
 }
 
+bool GPU_mem_stats_supported(void)
+{
+	return (GLEW_NVX_gpu_memory_info || (GLEW_ATI_meminfo)) && (G.debug & G_DEBUG_GPU_MEM);
+}
+
+
+void GPU_mem_stats_get(int *totalmem, int *freemem)
+{
+	if (GLEW_NVX_gpu_memory_info) {
+		/* returned value in Kb */
+		glGetIntegerv(GL_GPU_MEMORY_INFO_TOTAL_AVAILABLE_MEMORY_NVX, totalmem);
+
+		glGetIntegerv(GL_GPU_MEMORY_INFO_CURRENT_AVAILABLE_VIDMEM_NVX, freemem);
+	}
+	else if (GLEW_ATI_meminfo) {
+		int stats[4];
+
+		glGetIntegerv(GL_TEXTURE_FREE_MEMORY_ATI, stats);
+		*freemem = stats[0];
+		*totalmem = 0;
+	}
+	else {
+		*totalmem = 0;
+		*freemem = 0;
+	}
+}
+
+
 #if 0 /* unused */
 
 /* GPUPixelBuffer */