Merge pull request #527 from Prof9/master

Wii U Virtual Console color shader

res/shaders/wiiu.shader/manifest.ini

@@ -0,0 +1,11 @@
+[shader]
+name=Wii U
+author=Prof. 9
+description=Uses the color palette from the Wii U Virtual Console. Enable bilinear filtering to further mimic Wii U output.
+passes=1
+
+[pass.0]
+fragmentShader=wiiu.fs
+blend=1
+width=960
+height=640

res/shaders/wiiu.shader/wiiu.fs

@@ -0,0 +1,22 @@
+varying vec2 texCoord;
+uniform sampler2D tex;
+uniform vec2 texSize;
+
+const float scale[32] = float[](
+	  0.0/255.0,   6.0/255.0,  12.0/255.0,  18.0/255.0,  24.0/255.0,  31.0/255.0,  37.0/255.0,  43.0/255.0,
+	 49.0/255.0,  55.0/255.0,  61.0/255.0,  67.0/255.0,  73.0/255.0,  79.0/255.0,  86.0/255.0,  92.0/255.0,
+	 98.0/255.0, 104.0/255.0, 111.0/255.0, 117.0/255.0, 123.0/255.0, 129.0/255.0, 135.0/255.0, 141.0/255.0,
+	148.0/255.0, 154.0/255.0, 159.0/255.0, 166.0/255.0, 172.0/255.0, 178.0/255.0, 184.0/255.0, 191.0/255.0
+);
+
+void main() {
+	vec4 color = texture2D(tex, texCoord);
+	color.rgb = round(color.rgb * 31.0);
+	color = vec4(
+		scale[int(color.r)],
+		scale[int(color.g)],
+		scale[int(color.b)],
+		1.0
+	);
+	gl_FragColor = color;
+}