#6059: OpenGL2: Read depths from resolve fbo when msaa is on in RB_TestFlare().

code/renderergl2/tr_flares.c

@@ -277,6 +277,7 @@ void RB_TestFlare( flare_t *f ) {
 	qboolean		visible;
 	float			fade;
 	float			screenZ;
+	FBO_t           *oldFbo;
 
 	backEnd.pc.c_flareTests++;
 
@@ -284,9 +285,22 @@ void RB_TestFlare( flare_t *f ) {
 	// don't bother with another sync
 	glState.finishCalled = qfalse;
 
+	// if we're doing multisample rendering, read from the correct FBO
+	oldFbo = glState.currentFBO;
+	if (tr.msaaResolveFbo)
+	{
+		FBO_Bind(tr.msaaResolveFbo);
+	}
+
 	// read back the z buffer contents
 	qglReadPixels( f->windowX, f->windowY, 1, 1, GL_DEPTH_COMPONENT, GL_FLOAT, &depth );
 
+	// if we're doing multisample rendering, switch to the old FBO
+	if (tr.msaaResolveFbo)
+	{
+		FBO_Bind(oldFbo);
+	}
+
 	screenZ = backEnd.viewParms.projectionMatrix[14] / 
 		( ( 2*depth - 1 ) * backEnd.viewParms.projectionMatrix[11] - backEnd.viewParms.projectionMatrix[10] );