| |
| /* |
| ** Copyright (c) 2012 The Khronos Group Inc. |
| ** |
| ** Permission is hereby granted, free of charge, to any person obtaining a |
| ** copy of this software and/or associated documentation files (the |
| ** "Materials"), to deal in the Materials without restriction, including |
| ** without limitation the rights to use, copy, modify, merge, publish, |
| ** distribute, sublicense, and/or sell copies of the Materials, and to |
| ** permit persons to whom the Materials are furnished to do so, subject to |
| ** the following conditions: |
| ** |
| ** The above copyright notice and this permission notice shall be included |
| ** in all copies or substantial portions of the Materials. |
| ** |
| ** THE MATERIALS ARE PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| ** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| ** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
| ** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY |
| ** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, |
| ** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
| ** MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS. |
| */ |
| |
| |
| #ifdef GL_ES |
| precision mediump float; |
| #endif |
| varying vec4 color; |
| |
| // Function declarations. |
| float function(inout float par[3]); |
| bool is_all(const in float array[3], const in float value); |
| void set_all(out float array[3], const in float value); |
| |
| void main (void) |
| { |
| float par[3]; |
| float ret = 0.0; |
| |
| float gray = 0.0; |
| |
| // Initialize the entire array to 1.0. |
| set_all(par, 1.0); |
| |
| ret = function(par); |
| |
| // The parameter should be changed by the function and the function should return 1.0. |
| if(is_all(par, 0.0) && (ret == 1.0)) |
| { |
| gray = 1.0; |
| } |
| |
| gl_FragColor = vec4(gray, gray, gray, 1.0); |
| } |
| |
| // Function definition. |
| float function(inout float par[3]) |
| { |
| // Return the value of the array. |
| if(is_all(par, 1.0)) |
| { |
| // Test parameter qualifier (default is "in"). |
| set_all(par, 0.0); |
| |
| return 1.0; |
| } |
| else |
| return 0.0; |
| } |
| |
| bool is_all(const in float array[3], const in float value) |
| { |
| bool ret = true; |
| |
| if(array[0] != value) |
| ret = false; |
| if(array[1] != value) |
| ret = false; |
| if(array[2] != value) |
| ret = false; |
| |
| return ret; |
| } |
| |
| void set_all(out float array[3], const in float value) |
| { |
| array[0] = value; |
| array[1] = value; |
| array[2] = value; |
| } |