/shaders/fragment/curtains.fs

 1/*
 2 * Copyright (c) 2012 Adobe Systems Incorporated. All rights reserved.
 3 *
 4 * Licensed under the Apache License, Version 2.0 (the "License");
 5 * you may not use this file except in compliance with the License.
 6 * You may obtain a copy of the License at
 7 *
 8 *     http://www.apache.org/licenses/LICENSE-2.0
 9 *
10 * Unless required by applicable law or agreed to in writing, software
11 * distributed under the License is distributed on an "AS IS" BASIS,
12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13 * See the License for the specific language governing permissions and
14 * limitations under the License.
15 */
16
17precision mediump float;
18
19// Uniforms passed in from CSS
20
21uniform float amount;
22
23// Varyings
24
25varying float v_lighting;
26varying float xpos;
27
28// Main
29
30void main()
31{
32  float alpha = abs(xpos) <= (amount * 0.5) ? 0.0 : 1.0;
33
34  /* Remove any perspective artifacts */
35  if (amount == 1.0) alpha = 0.0;
36
37  css_ColorMatrix = mat4(
38       vec4(v_lighting, 0.0, 0.0, 0.0),
39        vec4(0.0, v_lighting, 0.0, 0.0),
40        vec4(0.0, 0.0, v_lighting, 0.0),
41        vec4(0.0, 0.0, 0.0, alpha)
42    );
43}