Implement low res shadows

shader/lighting/floor.vert

@@ -1,6 +1,6 @@
 #version 430 core
 layout (location = 0) in vec4 position;
-out vec2 vParams;
+//out vec2 vParams;
 
 uniform vec2 winSize;
 uniform float zoom;
@@ -10,6 +10,5 @@ uniform mat4 worldMat;
 
 void main()
 {
-  gl_Position = vec4(position.xy,0,1);
-  vParams = position.zw;
+  gl_Position = position;
 }