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I'd like to play around with Shadertoy's shaders. To start with, I would like to use this one: https://www.shadertoy.com/view/4slGRM. From what I gather, Shadertoy only has fragment shaders (am I right?). So I wrote a skeleton of a vertex shader that looks like this:
Code: [Select]
void main(void) {
}
I know, breathtaking, right? Still, GLSLShader tells me that the fragment shader (not my brilliant vertexshader, mind you) isn't compiled. How come?Quote
[ Wed Dec 11 23:02:13 EST 2013 ] - ERROR: Attached fragment shader is not compiled.
Code: [Select]
// Simple Water shader. (c) Victor Korsun, bitekas@gmail.com; 2012.
//
// Attribution-ShareAlike CC License.
#ifdef GL_ES
precision highp float;
#endif
const float PI = 3.1415926535897932;
// play with these parameters to custimize the effect
// ===================================================
//speed
const float speed = 0.2;
const float speed_x = 0.3;
const float speed_y = 0.3;
// refraction
const float emboss = 0.50;
const float intensity = 2.4;
const int steps = 8;
const float frequency = 6.0;
const int angle = 7; // better when a prime
// reflection
const float delta = 60.;
const float intence = 700.;
const float reflectionCutOff = 0.012;
const float reflectionIntence = 200000.;
// ===================================================
float time = iGlobalTime*1.3;
float col(vec2 coord)
{
float delta_theta = 2.0 * PI / float(angle);
float col = 0.0;
float theta = 0.0;
for (int i = 0; i < steps; i++)
{
vec2 adjc = coord;
theta = delta_theta*float(i);
adjc.x += cos(theta)*time*speed + time * speed_x;
adjc.y -= sin(theta)*time*speed - time * speed_y;
col = col + cos( (adjc.x*cos(theta) - adjc.y*sin(theta))*frequency)*intensity;
}
return cos(col);
}
//---------- main
void main(void)
{
vec2 p = (gl_FragCoord.xy) / iResolution.xy, c1 = p, c2 = p;
float cc1 = col(c1);
c2.x += iResolution.x/delta;
float dx = emboss*(cc1-col(c2))/delta;
c2.x = p.x;
c2.y += iResolution.y/delta;
float dy = emboss*(cc1-col(c2))/delta;
c1.x += dx*2.;
c1.y = -(c1.y+dy*2.);
float alpha = 1.+dot(dx,dy)*intence;
float ddx = dx - reflectionCutOff;
float ddy = dy - reflectionCutOff;
if (ddx > 0. && ddy > 0.)
alpha = pow(alpha, ddx*ddy*reflectionIntence);
vec4 col = texture2D(iChannel0,c1)*(alpha);
gl_FragColor = col;
}
