[require]
GLSL >= 1.10

[vertex shader]
varying vec4 gl_TexCoord[5];
void main()
{
	/* 0.05, 0.05, 0.10, 0.15, 0.20 */
	for (int i = 0; i < 5; i++)
		gl_TexCoord[i] = vec4(float(i) * 0.05);

	gl_Position = gl_Vertex;
}

[fragment shader]
varying vec4 gl_TexCoord[5];
void main()
{
	vec4 result = vec4(0.0);

	for (int i = 0; i < 4; i++)
		result += gl_TexCoord[i];

	/* 0.00 + 0.05 + 0.10 + 0.15 = 0.30 */
	gl_FragColor = result;
}

[test]
draw rect -1 -1 2 2
probe rgba 1 1 0.3 0.3 0.3 0.3