Add shaders that will just return positional information

2021-08-31 18:32:50 +01:00
parent f58530cbb1
commit 146bab6fe3
18 changed files with 336 additions and 2 deletions
@@ -0,0 +1,32 @@
+#version 430 core
+layout (triangles) in;
+layout (triangle_strip, max_vertices = 4) out;
+layout (std140, binding = 0) uniform TheMat { mat4 theMat; } ;
+out vec4 gPos;
+out vec2 gBoundingBox;
+void main()
+{
+  vec4 pas = gl_in[0].gl_Position;
+  vec4 pbs = gl_in[1].gl_Position;
+  vec4 pcs = gl_in[2].gl_Position;
+  vec4 pa = theMat * pas;
+  vec4 pb = theMat * pbs;
+  vec4 pc = theMat * pcs;
+  gBoundingBox = vec2 (-1,1);
+  gl_Position = pb; 
+  gPos = pbs;
+  EmitVertex();
+  gBoundingBox = vec2 (1,1);
+  gl_Position = pa;
+  gPos = pas;
+  EmitVertex();
+  gBoundingBox = vec2 (-1,-1);
+  gl_Position = pc;
+  gPos = pcs;
+  EmitVertex();
+  gBoundingBox = vec2 (1,-1);
+  gl_Position = pa + pc - pb;
+  gPos = pas + pcs - pbs;
+  EmitVertex();
+  EndPrimitive();
+}