95 lines
1.6 KiB
GLSL
95 lines
1.6 KiB
GLSL
#version 330
|
|
#extension GL_ARB_separate_shader_objects : enable
|
|
|
|
const float PI = 3.1415926535897932384626433832795;
|
|
const float PI_2 = 1.57079632679489661923;
|
|
|
|
layout(location=0) in vec2 inPos;
|
|
layout(location=1) in vec2 inTex;
|
|
|
|
out gl_PerVertex
|
|
{
|
|
vec4 gl_Position;
|
|
};
|
|
layout(location=1) out vec2 fsTex;
|
|
layout(location=2) out vec4 vertexColor;
|
|
|
|
uniform mat4 proj;
|
|
uniform mat4 world;
|
|
|
|
uniform vec4 colorCenter;
|
|
uniform vec4 colorMax;
|
|
|
|
uniform float maxSize;
|
|
|
|
// Polar coordinate utility functions
|
|
float hypot(vec2 pos)
|
|
{
|
|
return sqrt(pos.x * pos.x + pos.y * pos.y);
|
|
}
|
|
|
|
/*
|
|
float atan2(vec2 pos)
|
|
{
|
|
if (pos.x > 0)
|
|
{
|
|
return atan(pos.y / pos.x);
|
|
}
|
|
|
|
if (pos.x < 0 && pos.y >= 0)
|
|
{
|
|
return atan(pos.y / pos.x) + PI;
|
|
}
|
|
|
|
if (pos.x < 0 && pos.y < 0)
|
|
{
|
|
return atan(pos.y / pos.x) - PI;
|
|
}
|
|
|
|
if (pos.x == 0 && pos.y > 0)
|
|
{
|
|
return PI_2;
|
|
}
|
|
|
|
if (pos.x == 0 && pos.y < 0)
|
|
{
|
|
return -PI_2;
|
|
}
|
|
|
|
// The following is not mathematically correct, as it's undefined
|
|
return 0.0;
|
|
}
|
|
|
|
vec2 toPolar(vec2 cartesian)
|
|
{
|
|
return vec2(hypot(pos), atan2(pos));
|
|
}
|
|
*/
|
|
|
|
float lerp(float x, vec2 p0, vec2 p1)
|
|
{
|
|
return p0.y + (p1.y - p0.y) * ((x - p0.x)/(p1.x - p0.x));
|
|
}
|
|
|
|
// x is in [0.0, 1.0]
|
|
vec4 lerpColor(float x, vec4 color1, vec4 color2)
|
|
{
|
|
return color1 + (color2 - color1) * x;
|
|
}
|
|
|
|
vec4 coordToColor(vec2 pos, float maxSize)
|
|
{
|
|
float r = hypot(pos);
|
|
//float phi = atan2(pos);
|
|
|
|
float factor = lerp(r, vec2(0,0), vec2(maxSize,1));
|
|
|
|
return lerpColor(factor, colorCenter, colorMax);
|
|
}
|
|
|
|
void main()
|
|
{
|
|
gl_Position = proj * world * vec4(inPos.xy, 0, 1);
|
|
vertexColor = coordToColor(inPos.xy, maxSize);
|
|
}
|