Fix: OpenGL renders on graphics cards which do not support non-power-of-two

textures were stretched and the wrong size.

3 files changed, 22 insertions, 15 deletions

diff --git a/source/blender/gpu/GPU_extensions.h b/source/blender/gpu/GPU_extensions.h
index 965f317aa50..3fff79390e3 100644
--- a/source/blender/gpu/GPU_extensions.h
+++ b/source/blender/gpu/GPU_extensions.h
@@ -136,7 +136,7 @@ int GPU_texture_opengl_bindcode(GPUTexture *tex);
 GPUFrameBuffer *GPU_framebuffer_create(void);
 int GPU_framebuffer_texture_attach(GPUFrameBuffer *fb, GPUTexture *tex, char err_out[256]);
 void GPU_framebuffer_texture_detach(GPUFrameBuffer *fb, GPUTexture *tex);
-void GPU_framebuffer_texture_bind(GPUFrameBuffer *fb, GPUTexture *tex);
+void GPU_framebuffer_texture_bind(GPUFrameBuffer *fb, GPUTexture *tex, int w, int h);
 void GPU_framebuffer_texture_unbind(GPUFrameBuffer *fb, GPUTexture *tex);
 void GPU_framebuffer_free(GPUFrameBuffer *fb);
 
@@ -146,10 +146,11 @@ void GPU_framebuffer_restore(void);
    - wrapper around framebuffer and texture for simple offscreen drawing 
    - changes size if graphics card can't support it */
 
-GPUOffScreen *GPU_offscreen_create(int *width, int *height, char err_out[256]);
+GPUOffScreen *GPU_offscreen_create(int width, int height, char err_out[256]);
 void GPU_offscreen_free(GPUOffScreen *ofs);
 void GPU_offscreen_bind(GPUOffScreen *ofs);
 void GPU_offscreen_unbind(GPUOffScreen *ofs);
+void GPU_offscreen_read_pixels(GPUOffScreen *ofs, int type, void *pixels);
 
 /* GPU Shader
    - only for fragment shaders now
diff --git a/source/blender/gpu/intern/gpu_extensions.c b/source/blender/gpu/intern/gpu_extensions.c
index 6189062a855..e1a89daf7e2 100644
--- a/source/blender/gpu/intern/gpu_extensions.c
+++ b/source/blender/gpu/intern/gpu_extensions.c
@@ -790,7 +790,7 @@ void GPU_framebuffer_texture_detach(GPUFrameBuffer *fb, GPUTexture *tex)
 	tex->fb = NULL;
 }
 
-void GPU_framebuffer_texture_bind(GPUFrameBuffer *UNUSED(fb), GPUTexture *tex)
+void GPU_framebuffer_texture_bind(GPUFrameBuffer *UNUSED(fb), GPUTexture *tex, int w, int h)
 {
 	/* push attributes */
 	glPushAttrib(GL_ENABLE_BIT);
@@ -801,7 +801,7 @@ void GPU_framebuffer_texture_bind(GPUFrameBuffer *UNUSED(fb), GPUTexture *tex)
 	glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, tex->fb->object);
 
 	/* push matrices and set default viewport and matrix */
-	glViewport(0, 0, tex->w, tex->h);
+	glViewport(0, 0, w, h);
 	GG.currentfb = tex->fb->object;
 
 	glMatrixMode(GL_PROJECTION);
@@ -859,13 +859,19 @@ struct GPUOffScreen {
 	GPUFrameBuffer *fb;
 	GPUTexture *color;
 	GPUTexture *depth;
+
+	/* requested width/height, may be smaller than actual texture size due
+	   to missing non-power of two support, so we compensate for that */
+	int w, h;
 };
 
-GPUOffScreen *GPU_offscreen_create(int *width, int *height, char err_out[256])
+GPUOffScreen *GPU_offscreen_create(int width, int height, char err_out[256])
 {
 	GPUOffScreen *ofs;
 
 	ofs= MEM_callocN(sizeof(GPUOffScreen), "GPUOffScreen");
+	ofs->w= width;
+	ofs->h= height;
 
 	ofs->fb = GPU_framebuffer_create();
 	if(!ofs->fb) {
@@ -873,24 +879,18 @@ GPUOffScreen *GPU_offscreen_create(int *width, int *height, char err_out[256])
 		return NULL;
 	}
 
-	ofs->depth = GPU_texture_create_depth(*width, *height, err_out);
+	ofs->depth = GPU_texture_create_depth(width, height, err_out);
 	if(!ofs->depth) {
 		GPU_offscreen_free(ofs);
 		return NULL;
 	}
 
-	if(*width!=ofs->depth->w || *height!=ofs->depth->h) {
-		*width= ofs->depth->w;
-		*height= ofs->depth->h;
-		printf("Offscreen size differs from given size!\n");
-	}
-	
 	if(!GPU_framebuffer_texture_attach(ofs->fb, ofs->depth, err_out)) {
 		GPU_offscreen_free(ofs);
 		return NULL;
 	}
 
-	ofs->color = GPU_texture_create_2D(*width, *height, NULL, err_out);
+	ofs->color = GPU_texture_create_2D(width, height, NULL, err_out);
 	if(!ofs->color) {
 		GPU_offscreen_free(ofs);
 		return NULL;
@@ -921,7 +921,7 @@ void GPU_offscreen_free(GPUOffScreen *ofs)
 void GPU_offscreen_bind(GPUOffScreen *ofs)
 {
 	glDisable(GL_SCISSOR_TEST);
-	GPU_framebuffer_texture_bind(ofs->fb, ofs->color);
+	GPU_framebuffer_texture_bind(ofs->fb, ofs->color, ofs->w, ofs->h);
 }
 
 void GPU_offscreen_unbind(GPUOffScreen *ofs)
@@ -931,6 +931,11 @@ void GPU_offscreen_unbind(GPUOffScreen *ofs)
 	glEnable(GL_SCISSOR_TEST);
 }
 
+void GPU_offscreen_read_pixels(GPUOffScreen *ofs, int type, void *pixels)
+{
+	glReadPixels(0, 0, ofs->w, ofs->h, GL_RGBA, type, pixels);
+}
+
 /* GPUShader */
 
 struct GPUShader {
diff --git a/source/blender/gpu/intern/gpu_material.c b/source/blender/gpu/intern/gpu_material.c
index d0f834977c8..26c08f6cae5 100644
--- a/source/blender/gpu/intern/gpu_material.c
+++ b/source/blender/gpu/intern/gpu_material.c
@@ -1661,7 +1661,8 @@ void GPU_lamp_shadow_buffer_bind(GPULamp *lamp, float viewmat[][4], int *winsize
 
 	/* opengl */
 	glDisable(GL_SCISSOR_TEST);
-	GPU_framebuffer_texture_bind(lamp->fb, lamp->tex);
+	GPU_framebuffer_texture_bind(lamp->fb, lamp->tex,
+		GPU_texture_opengl_width(lamp->tex), GPU_texture_opengl_height(lamp->tex));
 
 	/* set matrices */
 	copy_m4_m4(viewmat, lamp->viewmat);