Move towards geometry instancing for shadows

shader/shadow/cap.vert

@@ -0,0 +1,11 @@
+#version 450 core
+layout (location = 0) in vec3 position;
+layout (std140, binding = 0) uniform TheMat { mat4 theMat; } ;
+uniform vec3 lightPos;
+uniform vec4 lumRad;
+out vec3 dField;
+out vec3 lum;
+void main()
+{
+    gl_Position = vec4(position,1);
+}