Immediate Mode: replacing glPushAttrib/glPopAttrib

Reference document: http://docs.gl/gl3/glPushAttrib

This patch only tackles the bits that are set by Blender with the
following exceptions:

1) Deprecated states (e.g., GL_STIPPLE) are not saved/restored

2) The exception being GL_ALPHA_TEST, which will be removed, but it may
affect drawing too much now. To be removed once we no longer set GL_ALPHA_TEST
elsewhere.

3) paint_cursor will be tackled separated, since it was abusing
glPush/PopAttrib in the first place.

4) Despite what the glPushAttrib page above may suggest, GL_DEPTH_WRITEMASK needs glGet, not glIsEnabled

5) BGE is still a problem since it relies on GL_ALL_ATTRIB_BITS which
would lead to a way more complete/lenghty solution. Since the BGE has
other (OpenGL deprecated) problems anyways, it can be handled on its own
time.

Finally, the original design for 2.8 was to implement a proper stack
system. However we need to move to core profile sooner than later. So
this is a pragmatic temporary (that may be permanent) solution.

Reviewers: merwin, campbellbarton

Differential Revision: https://developer.blender.org/D2600

1 files changed, 6 insertions, 2 deletions

diff --git a/source/blender/gpu/intern/gpu_select_pick.c b/source/blender/gpu/intern/gpu_select_pick.c
index 780ffd82671..da75925fe66 100644
--- a/source/blender/gpu/intern/gpu_select_pick.c
+++ b/source/blender/gpu/intern/gpu_select_pick.c
@@ -31,6 +31,8 @@
 #include <stdlib.h>
 #include <float.h>
 
+#include "GPU_immediate.h"
+#include "GPU_draw.h"
 #include "GPU_select.h"
 #include "GPU_extensions.h"
 #include "GPU_glew.h"
@@ -291,6 +293,8 @@ typedef struct GPUPickState {
 			unsigned int *rect_id;
 		} nearest;
 	};
+
+	struct GPUStateValues attribs;
 } GPUPickState;
 
 
@@ -316,8 +320,8 @@ void gpu_select_pick_begin(
 
 	/* Restrict OpenGL operations for when we don't have cache */
 	if (ps->is_cached == false) {
+		gpuSaveState(&ps->attribs, GPU_DEPTH_BUFFER_BIT | GPU_VIEWPORT_BIT);
 
-		glPushAttrib(GL_DEPTH_BUFFER_BIT | GL_VIEWPORT_BIT);
 		/* disable writing to the framebuffer */
 		glColorMask(GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
 
@@ -536,7 +540,7 @@ unsigned int gpu_select_pick_end(void)
 			gpu_select_pick_load_id(ps->gl.prev_id);
 		}
 
-		glPopAttrib();
+		gpuRestoreState(&ps->attribs);
 		glColorMask(GL_TRUE, GL_TRUE, GL_TRUE, GL_TRUE);
 	}