[Bf-committers] Preview Render Patch

[Matthew H. Plough]

Hi everyone,

I was sick and tired of the stupid lines showing up for no apparent 
reason in material previews, so I decided to do something about it.  
Instead of rendering with unreliable copy pixels and scanlines, I render 
by making the rendered image into a texture, and mapping it onto a 
quadrilateral.  The resulting code is very clean and easy to 
understand.  It is reusable, and is much simpler than the current 
implementation.  I hope it can make it in for the release.

The patch is attached.

Matt
-------------- next part --------------
Index: previewrender.c
===================================================================
RCS file: /cvsroot/bf-blender/blender/source/blender/src/previewrender.c,v
retrieving revision 1.58
diff -u -p -u -r1.58 previewrender.c
--- previewrender.c	17 Apr 2005 17:43:07 -0000	1.58
+++ previewrender.c	26 May 2005 06:15:58 -0000
@@ -94,8 +94,8 @@
 #include "blendef.h"	/* CLAMP */
 #include "interface.h"	/* ui_graphics_to_window() SOLVE! (ton) */
 
-#define PR_RECTX	141
-#define PR_RECTY	141
+#define PR_RECTX	256
+#define PR_RECTY	256
 #define PR_XMIN		10
 #define PR_YMIN		5
 #define PR_XMAX		200
@@ -378,17 +378,50 @@ void BIF_previewdraw(void)
 {
 	SpaceButs *sbuts= curarea->spacedata.first;
 	
+	fprintf(stderr, "curarea->spacedata.first: PR_RECTX = %d, PR_RECTY = %d\n", 
+		PR_RECTX, PR_RECTY);
+	
 	if (sbuts->rect==0) BIF_preview_changed(sbuts);
 	else {
-		int y;
+		GLuint texid;
+		
+		/* generate the texture here for now and bind it */
+		glEnable(GL_TEXTURE_2D);
+		glGenTextures(1, &texid);
+		/* texid is 0 if there is a problem */
+		glBindTexture(GL_TEXTURE_2D, texid);
 
-		set_previewrect(sbuts->area->win, PR_XMIN, PR_YMIN, PR_XMAX, PR_YMAX);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
 		
-		for (y=0; y<PR_RECTY; y++) {
-			display_pr_scanline(sbuts->rect, y);
-		}
+		glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
 
-		end_previewrect();
+
+		glTexImage2D(GL_TEXTURE_2D, 0, 4, PR_RECTX, PR_RECTY, 0, GL_RGBA, 
+			GL_UNSIGNED_BYTE, sbuts->rect);
+		
+		
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
+		glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
+		glDisable(GL_BLEND); /* it looks weird with blending on */
+		
+		glBindTexture(GL_TEXTURE_2D, texid);
+		glColor4f(1, 1, 1, 1);
+		
+		glBegin(GL_POLYGON);
+		glTexCoord2f(0.0, 0.0); glVertex2f(PR_XMIN, PR_YMIN);
+		glTexCoord2f(0.0, 1.0); glVertex2f(PR_XMIN, PR_YMAX);
+		glTexCoord2f(1.0, 1.0); glVertex2f(PR_XMAX, PR_YMAX);
+		glTexCoord2f(1.0, 0.0); glVertex2f(PR_XMAX, PR_YMIN);
+		glEnd();
+		
+		/* delete the texture here for now */
+		glDisable(GL_TEXTURE_2D);
+		glDeleteTextures(1, &texid);
 		
 		if (sbuts->mainb==CONTEXT_SHADING && sbuts->tab[CONTEXT_SHADING]==TAB_SHADING_TEX) {
 			draw_tex_crop(sbuts->lockpoin);
@@ -592,10 +625,7 @@ static void previewflare(SpaceButs *sbut
 	// not sure why, either waitcursor or renderflare screws up (disabled then)
 	//areawinset(curarea->win);
 	
-	/* draw can just be this way, all settings are OK */
-	for (y=0; y<PR_RECTY; y++) {
-		display_pr_scanline(sbuts->rect, y);
-	}
+	BIF_previewdraw();
 	
 	/* temps */
 	R.ycor= ycor;
@@ -1167,7 +1197,7 @@ void BIF_previewrender(SpaceButs *sbuts)
 
 	uiPanelPush(block);	// sets UImat
 	
-	set_previewrect(sbuts->area->win, PR_XMIN, PR_YMIN, PR_XMAX, PR_YMAX); // uses UImat
+	/*set_previewrect(sbuts->area->win, PR_XMIN, PR_YMIN, PR_XMAX, PR_YMAX);*/ // uses UImat
 
 	if(sbuts->rect==NULL) {
 		sbuts->rect= MEM_callocN(sizeof(int)*PR_RECTX*PR_RECTY, "butsrect");
@@ -1291,7 +1321,7 @@ void BIF_previewrender(SpaceButs *sbuts)
 			}
 		}
 
-		display_pr_scanline(sbuts->rect, sbuts->cury);
+		BIF_previewdraw();
 		
 		/* flush opengl for cards with frontbuffer slowness */
 		if(sbuts->cury==PR_RECTY-1 || (PIL_check_seconds_timer() - lasttime > 0.05)) {
@@ -1302,7 +1332,7 @@ void BIF_previewrender(SpaceButs *sbuts)
 		sbuts->cury++;
 	}
 
-	end_previewrect();
+	/*end_previewrect();*/
 	
 	if(sbuts->cury>=PR_RECTY && tex) 
 		if (sbuts->tab[CONTEXT_SHADING]==TAB_SHADING_TEX)