You cannot select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
78 lines
1.8 KiB
GLSL
78 lines
1.8 KiB
GLSL
// Author @patriciogv - 2015
|
|
// http://patriciogonzalezvivo.com
|
|
|
|
#ifdef GL_ES
|
|
precision mediump float;
|
|
#endif
|
|
|
|
#define PI 3.1415926535
|
|
#define HALF_PI 1.57079632679
|
|
|
|
uniform vec2 u_resolution;
|
|
uniform float u_time;
|
|
|
|
uniform sampler2D u_tex0;
|
|
uniform vec2 u_tex0Resolution;
|
|
|
|
float speedMoon = 0.01;
|
|
float speedSun = 0.25;
|
|
|
|
vec3 sphereNormals(in vec2 uv) {
|
|
uv = fract(uv)*2.0-1.0;
|
|
vec3 ret;
|
|
ret.xy = sqrt(uv * uv) * sign(uv);
|
|
ret.z = sqrt(abs(1.0 - dot(ret.xy,ret.xy)));
|
|
ret = ret * 0.5 + 0.5;
|
|
return mix(vec3(0.0), ret, smoothstep(1.0,0.98,dot(uv,uv)) );
|
|
}
|
|
|
|
vec2 sphereCoords(vec2 _st, float _scale){
|
|
float maxFactor = sin(1.570796327);
|
|
vec2 uv = vec2(0.0);
|
|
vec2 xy = 2.0 * _st.xy - 1.0;
|
|
float d = length(xy);
|
|
if (d < (2.0-maxFactor)){
|
|
d = length(xy * maxFactor);
|
|
float z = sqrt(1.0 - d * d);
|
|
float r = atan(d, z) / 3.1415926535 * _scale;
|
|
float phi = atan(xy.y, xy.x);
|
|
|
|
uv.x = r * cos(phi) + 0.5;
|
|
uv.y = r * sin(phi) + 0.5;
|
|
} else {
|
|
uv = _st.xy;
|
|
}
|
|
return uv;
|
|
}
|
|
|
|
vec4 sphereTexture(in sampler2D _tex, in vec2 _uv) {
|
|
vec2 st = sphereCoords(_uv, 1.0);
|
|
|
|
float aspect = u_tex0Resolution.y/u_tex0Resolution.x;
|
|
st.x = fract(st.x*aspect + u_time*speedMoon);
|
|
|
|
return texture2D(_tex, st);
|
|
}
|
|
|
|
void main(){
|
|
vec2 st = gl_FragCoord.xy/u_resolution.xy;
|
|
vec3 color = vec3(1.0);
|
|
|
|
color *= sphereTexture(u_tex0, st).rgb;
|
|
|
|
// Calculate sun direction
|
|
vec3 sunPos = normalize(vec3(cos(u_time*speedSun-HALF_PI),0.0,sin(speedSun*u_time-HALF_PI)));
|
|
vec3 surface = normalize(sphereNormals(st)*2.0-1.0);
|
|
|
|
// Add Shadows
|
|
color *= dot(sunPos,surface);
|
|
|
|
// Blend black the edge of the sphere
|
|
float radius = 1.0-length( vec2(0.5)-st )*2.0;
|
|
color *= smoothstep(0.001,0.05,radius);
|
|
|
|
color = 1.0-color;
|
|
|
|
gl_FragColor = vec4(color,1.0);
|
|
}
|