experimental map shaders

modules/game_shaders/shaders/fog.frag

@@ -0,0 +1,18 @@
+uniform float u_Time;
+uniform sampler2D u_Tex0;
+uniform sampler2D u_Tex1;
+varying vec2 v_TexCoord;
+
+vec2 direction = vec2(1.0,0.3);
+float speed = 0.05;
+float pressure = 0.6;
+float zoom = 0.5;
+
+void main(void)
+{
+    vec2 offset = (v_TexCoord + (direction * u_Time * speed)) / zoom;
+    vec3 bgcol = texture2D(u_Tex0, v_TexCoord).xyz;
+    vec3 fogcol = texture2D(u_Tex1, offset).xyz;
+    vec3 col = bgcol + fogcol*pressure;
+    gl_FragColor = vec4(col,1.0);
+}