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# Test generated by:
# ../variable-index-read.sh 1.00
[require]
GLSL ES >= 1.00
GL ES >= 2.0
[vertex shader]
attribute vec4 vertex;
mat4 projection = mat4(
2.0/250.0, 0.0, 0.0, -1.0,
0.0, 2.0/250.0, 0.0, -1.0,
0.0, 0.0, -1.0, 0.0,
0.0, 0.0, 0.0, 1.0);
uniform int col;
uniform vec2 expect;
varying mat2 m;
varying vec4 color;
void main()
{
gl_Position = vertex;
gl_Position *= projection;
m = mat2(1.0, 2.0, 3.0, 4.0);
/* From page 23 (page 30 of the PDF) of the GLSL 1.10 spec:
*
* "A vertex shader may also read varying variables, getting back the
* same values it has written. Reading a varying variable in a vertex
* shader returns undefined values if it is read before being
* written."
*/
color = (m[col] == expect)
? vec4(0.0, 1.0, 0.0, 1.0) : vec4(1.0, 0.0, 0.0, 1.0);
}
[fragment shader]
uniform int col;
uniform vec2 expect;
varying mat2 m;
varying vec4 color;
void main()
{
/* There is some trickery here. The fragment shader has to actually use
* the varyings generated by the vertex shader, or the compiler (more
* likely the linker) might demote the varying outputs to just be vertex
* shader global variables. Since the point of the test is the vertex
* shader reading from a varying, that would defeat the test.
*/
gl_FragColor = (m[col] == expect)
? color : vec4(1.0, 0.0, 0.0, 1.0);
}
[test]
clear color 0.5 0.5 0.5 0.5
clear
uniform int col 0
uniform vec2 expect 1 2
draw rect 5 5 10 10
probe rgb 10 10 0.0 1.0 0.0
uniform int col 1
uniform vec2 expect 3 4
draw rect 20 5 10 10
probe rgb 25 10 0.0 1.0 0.0
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