PSP rendering and shader cleanup

src/extras/shaders/scale_PS.hlsl

@@ -12,8 +12,8 @@ float4 colorscale : register(c1);
 float4 main(VS_out input) : COLOR
 {
 	float4 color = input.Color;
-	color *= tex2D(tex0, input.TexCoord0.xy);
-	color *= colorscale;
+	color *= tex2D(tex0, input.TexCoord0.xy)*colorscale;
+	color.rgb = clamp(color.rgb, 0.0, 1.0);
 	color.rgb = lerp(fogColor.rgb, color.rgb, input.TexCoord0.z);
 	return color;
 }