Subversion Repositories gelsvn

#version 120

#extension GL_EXT_gpu_shader4 : enable

uniform sampler2DRect mesh_tex;

uniform vec2 WIN_SCALE;

noperspective varying float n;

varying in vec4 diffuseIn[1];

varying vec4 diffuse;

noperspective varying float dist[20];

float distance(vec2 p, vec2 p0, vec2 p1)

{

	vec2 v0 = p1-p0;

	vec2 v1 = p0-p;

	vec2 v2 = p1-p;

	return abs(v1.x*v2.y - v1.y * v2.x)/length(v0);

}

void main(void)

{

	int N = int(gl_PositionIn[0].z);

	n=gl_PositionIn[0].z;

	diffuse = diffuseIn[0];

	vec2 v_idx = gl_PositionIn[0].xy;

	vec4 p3d[20];

	vec2 p[20];

	for(int i=0;i<N;++i)

		{

			p3d[i] = gl_ModelViewProjectionMatrix*texture2DRect(mesh_tex, v_idx);

			p[i] = WIN_SCALE * p3d[i].xy/p3d[i].w;

			v_idx.x++;

		}

	for(int l=0;l<N;++l)

	{

		int i = (l%2==0) ? l/2 : N-(l+1)/2;

		for(int j=0;j<N;++j)

			dist[j] = distance(p[i],p[j],p[(j+1)%N]);

		gl_Position = p3d[i];

		EmitVertex();

	}

	EndPrimitive();

}