aboutsummaryrefslogtreecommitdiff
path: root/packages/noncvs/windows/extra/Gem/examples/10.glsl/tri2fan.geom
blob: 45961e25cc1fb2f63a82c92f51b71f9a97bcc3f9 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
// Cyrille Henry 2010

#version 120 
#extension GL_EXT_geometry_shader4 : enable

void main(void)
{
	
	int i; //increment variable
	vec4 pos1,pos2, pos3, pos4, pos5; // tmp
	vec3 high;

	for(i=0; i< gl_VerticesIn; i += 3){ // for all triangles
		pos1 = gl_PositionIn[i];
		pos2 = gl_PositionIn[i+1];
		pos3 = gl_PositionIn[i+2];
		pos4 = (pos1 + pos2 + pos3) / 3.; // center of the triangle

		high = 10.*cross(pos2.xyz-pos1.xyz,pos3.xyz-pos2.xyz); 
			// hight and orientation of the piramide

		high = normalize(high);
		high *= length(pos2-pos1);
		pos5 = pos4 ;
        pos5.xyz += high;

		gl_Position = gl_ModelViewProjectionMatrix * pos1;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos4;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos5;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos2;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos4;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos5;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos3;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos4;
		EmitVertex();
		gl_Position = gl_ModelViewProjectionMatrix * pos5;
		EmitVertex();

		EndPrimitive();	
			// new primitive
	}

}