stars wip

src/shaders/blendSkyboxStars.frag

@@ -0,0 +1,38 @@
+#version 150
+#ifdef GL_ES
+    precision mediump float;
+#endif
+
+
+in vec4 v_color;
+in vec2 v_texCoords;
+uniform sampler2D u_texture; // world texture, has alpha value that is meaningful
+
+uniform sampler2D tex1; // glow texture, SHOULD contain alpha of all 1.0
+out vec4 fragColor;
+
+vec2 boolean = vec2(0.0, 1.0);
+
+uniform vec2 screenSize;
+uniform vec2 drawOffset; // value of the 'gradY'
+uniform vec2 drawOffsetSize; // value of the 'gradH'
+uniform vec2 skyboxUV1; // (u, v) for the skybox drawing
+uniform vec2 skyboxUV2; // (u2, v2) for the skybox drawing
+uniform vec2 tex1Size = vec2(4096.0, 4096.0);
+uniform vec2 astrumScroll = vec2(0.0, 0.0);
+
+
+// draw call to this function must use UV coord of (0,0,1,1)!
+void main(void) {
+    vec2 skyboxTexCoord = mix(skyboxUV1, skyboxUV2, v_texCoords);
+    vec2 astrumTexCoord = (v_texCoords * drawOffsetSize + drawOffset + astrumScroll) / tex1Size;
+
+
+    vec4 colorTex0 = texture(u_texture, skyboxTexCoord); // lightmap (RGB) pre-mixed
+    vec4 colorTex1 = texture(tex1, astrumTexCoord); // lightmap (A) pre-mixed
+
+
+
+//    fragColor = (max(colorTex0, colorTex1) * boolean.yyyx) + boolean.xxxy;
+    fragColor = colorTex0;
+}