blob: 874ea84088846c484308eafa87f295b0f19595e2 [file] [log] [blame] [edit]
#version 310 es
#extension GL_EXT_tessellation_shader : require
#extension GL_EXT_gpu_shader5 : require
layout(triangles, equal_spacing) in;
layout(location = 0) in highp vec2 in_te_position[];
layout(location = 0) out mediump vec4 in_f_color;
precise gl_Position;
void main(void) {
highp vec2 pos = gl_TessCoord.x * in_te_position[0] +
gl_TessCoord.y * in_te_position[1] +
gl_TessCoord.z * in_te_position[2];
highp float f =
sqrt(3.0 * min(gl_TessCoord.x, min(gl_TessCoord.y, gl_TessCoord.z))) *
0.5 +
0.5;
in_f_color = vec4(gl_TessCoord * f, 1.0);
// Offset the position slightly, based on the parity of the bits in the float
// representation.
// This is done to detect possible small differences in edge vertex positions
// between patches.
uvec2 bits = floatBitsToUint(pos);
uint numBits = 0u;
for (uint i = 0u; i < 32u; i++)
numBits +=
((bits[0] << i) & 1u) + ((bits[1] << i) & 1u);
pos += float(numBits & 1u) * 0.04;
gl_Position = vec4(pos, 0.0, 1.0);
}