oglrender: support wireframe

desmume/src/OGLRender.cpp

@@ -829,6 +829,7 @@ static void OGLRender()
 
 			VERT *vert0 = &gfx3d.vertlist->list[poly->vertIndexes[0]];
 			u8 alpha =	material_5bit_to_8bit[poly->getAlpha()];
+			if(wireframe) alpha = 255;
 			u8 color0[4] = {
 					material_5bit_to_8bit[vert0->color[0]],
 					material_5bit_to_8bit[vert0->color[1]],
@@ -836,6 +837,9 @@ static void OGLRender()
 					alpha
 				};
 
+			//this draws things as a fan to prepare for the day when the clipping is done in gfx3d
+			//and funny shaped polys find their way into here.
+			//of course it could really be drawn as a fan, i suppose.. i dont remember why we did it this way
 			for(int j = 1; j < (type-1); j++)
 			{
 				VERT *vert1 = &gfx3d.vertlist->list[poly->vertIndexes[j]];

desmume/src/gfx3d.cpp

@@ -546,9 +546,6 @@ static void gfx3d_glPolygonAttrib_cache()
 
 	// back face culling
 	cullingMask = (polyAttr>>6)&3;
-
-	// Alpha value, actually not well handled, 0 should be wireframe
-	colorRGB[3] = colorAlpha = ((polyAttr>>16)&0x1F);
 }
 
 static void gfx3d_glTexImage_cache()

desmume/src/gfx3d.h

@@ -84,7 +84,8 @@ struct POLY {
 	bool isTranslucent()
 	{
 		//alpha != 31 -> translucent
-		if((polyAttr&0x001F0000) != 0x001F0000) 
+		//except for alpha 0 which is wireframe (unless it has a translucent tex)
+		if((polyAttr&0x001F0000) != 0x001F0000 && (polyAttr&0x001F0000) != 0)
 			return true;
 		int texFormat = (texParam>>26)&7;