Draw Manager: OpenGL render support

Works for clay-engine but doesn't draw objects with eevee.

4 files changed, 34 insertions, 0 deletions

diff --git a/source/blender/gpu/GPU_framebuffer.h b/source/blender/gpu/GPU_framebuffer.h
index 349e11ceb44..92f5d8a3796 100644
--- a/source/blender/gpu/GPU_framebuffer.h
+++ b/source/blender/gpu/GPU_framebuffer.h
@@ -84,6 +84,10 @@ int GPU_offscreen_width(const GPUOffScreen *ofs);
 int GPU_offscreen_height(const GPUOffScreen *ofs);
 int GPU_offscreen_color_texture(const GPUOffScreen *ofs);
 
+void GPU_offscreen_viewport_data_get(
+        GPUOffScreen *ofs,
+        GPUFrameBuffer **r_fb, struct GPUTexture **r_color, struct GPUTexture **r_depth);
+
 #ifdef __cplusplus
 }
 #endif
diff --git a/source/blender/gpu/GPU_viewport.h b/source/blender/gpu/GPU_viewport.h
index 93bf96a5830..2585fcae24c 100644
--- a/source/blender/gpu/GPU_viewport.h
+++ b/source/blender/gpu/GPU_viewport.h
@@ -88,6 +88,9 @@ void GPU_viewport_bind(GPUViewport *viewport, const rcti *rect);
 void GPU_viewport_unbind(GPUViewport *viewport);
 void GPU_viewport_free(GPUViewport *viewport);
 
+GPUViewport *GPU_viewport_create_from_offscreen(struct GPUOffScreen *ofs);
+void GPU_viewport_clear_from_offscreen(GPUViewport *viewport);
+
 void *GPU_viewport_engine_data_create(GPUViewport *viewport, void *engine_type);
 void *GPU_viewport_engine_data_get(GPUViewport *viewport, void *engine_type);
 void *GPU_viewport_framebuffer_list_get(GPUViewport *viewport);
diff --git a/source/blender/gpu/intern/gpu_framebuffer.c b/source/blender/gpu/intern/gpu_framebuffer.c
index 52e9a6aec3a..09e80eeac9e 100644
--- a/source/blender/gpu/intern/gpu_framebuffer.c
+++ b/source/blender/gpu/intern/gpu_framebuffer.c
@@ -682,3 +682,12 @@ int GPU_offscreen_color_texture(const GPUOffScreen *ofs)
 	return GPU_texture_opengl_bindcode(ofs->color);
 }
 
+/* only to be used by viewport code! */
+void GPU_offscreen_viewport_data_get(
+        GPUOffScreen *ofs,
+        GPUFrameBuffer **r_fb, GPUTexture **r_color, GPUTexture **r_depth)
+{
+	*r_fb = ofs->fb;
+	*r_color = ofs->color;
+	*r_depth = ofs->depth;
+}
\ No newline at end of file
diff --git a/source/blender/gpu/intern/gpu_viewport.c b/source/blender/gpu/intern/gpu_viewport.c
index 94c2b022e86..98c3613e1e2 100644
--- a/source/blender/gpu/intern/gpu_viewport.c
+++ b/source/blender/gpu/intern/gpu_viewport.c
@@ -83,6 +83,24 @@ GPUViewport *GPU_viewport_create(void)
 	return viewport;
 }
 
+GPUViewport *GPU_viewport_create_from_offscreen(struct GPUOffScreen *ofs)
+{
+	GPUViewport *viewport = GPU_viewport_create();
+	GPU_offscreen_viewport_data_get(ofs, &viewport->fbl->default_fb, &viewport->txl->color, &viewport->txl->depth);
+	viewport->size[0] = GPU_offscreen_width(ofs);
+	viewport->size[1] = GPU_offscreen_height(ofs);
+	return viewport;
+}
+/**
+ * Clear vars assigned from offscreen, so we don't free data owned by `GPUOffScreen`.
+ */
+void GPU_viewport_clear_from_offscreen(GPUViewport *viewport)
+{
+	viewport->fbl->default_fb = NULL;
+	viewport->txl->color = NULL;
+	viewport->txl->depth = NULL;
+}
+
 void *GPU_viewport_engine_data_create(GPUViewport *viewport, void *engine_type)
 {
 	LinkData *ld = MEM_callocN(sizeof(LinkData), "LinkData");