mirror of
https://github.com/patriciogonzalezvivo/thebookofshaders
synced 2024-11-01 21:40:27 +00:00
41 lines
1021 B
GLSL
41 lines
1021 B
GLSL
// Author @patriciogv ( patriciogonzalezvivo.com ) - 2015
|
|
|
|
#ifdef GL_ES
|
|
precision mediump float;
|
|
#endif
|
|
|
|
uniform vec2 u_resolution;
|
|
uniform float u_time;
|
|
|
|
float box(in vec2 _st, in vec2 _size){
|
|
_size = vec2(0.5) - _size*0.5;
|
|
vec2 uv = smoothstep(_size,
|
|
_size+vec2(0.001),
|
|
_st);
|
|
uv *= smoothstep(_size,
|
|
_size+vec2(0.001),
|
|
vec2(1.0)-_st);
|
|
return uv.x*uv.y;
|
|
}
|
|
|
|
float cross(in vec2 _st, float _size){
|
|
return box(_st, vec2(_size,_size/4.)) +
|
|
box(_st, vec2(_size/4.,_size));
|
|
}
|
|
|
|
void main(){
|
|
vec2 st = gl_FragCoord.xy/u_resolution.xy;
|
|
vec3 color = vec3(0.0);
|
|
|
|
// To move the cross we move the space
|
|
vec2 translate = vec2(cos(u_time),sin(u_time));
|
|
st += translate*0.35;
|
|
|
|
// Show the coordinates of the space on the background
|
|
// color = vec3(st.x,st.y,0.0);
|
|
|
|
// Add the shape on the foreground
|
|
color += vec3(cross(st,0.25));
|
|
|
|
gl_FragColor = vec4(color,1.0);
|
|
} |