Modified the GLSL surface texture program to use multiple varyings instead of an array of varyings

Author: pdavidc

worldwind/src/main/res/raw/gov_nasa_worldwind_surfacetextureprogram_frag.glsl

@@ -10,24 +10,25 @@ uniform bool enableTexture;
 uniform vec4 color;
 uniform sampler2D texSampler;
 
-varying vec2 texCoord[2];
+varying vec2 texCoord;
+varying vec2 tileCoord;
 
 void main() {
     /* Using the second texture coordinate, compute a mask that's 1.0 when the fragment is inside the surface tile, and
        0.0 otherwise. */
-    float sMask = step(0.0, texCoord[1].s) * (1.0 - step(1.0, texCoord[1].s));
-    float tMask = step(0.0, texCoord[1].t) * (1.0 - step(1.0, texCoord[1].t));
+    float sMask = step(0.0, tileCoord.s) * (1.0 - step(1.0, tileCoord.s));
+    float tMask = step(0.0, tileCoord.t) * (1.0 - step(1.0, tileCoord.t));
     float tileMask = sMask * tMask;
 
     if (enablePickMode && enableTexture) {
         /* Using the first texture coordinate, modulate the RGBA color with the 2D texture's Alpha component (rounded to
            0.0 or 1.0). Finally, modulate the result by the tile mask to suppress fragments outside the surface tile. */
-        float texMask = floor(texture2D(texSampler, texCoord[0]).a + 0.5);
+        float texMask = floor(texture2D(texSampler, texCoord).a + 0.5);
         gl_FragColor = color * texMask * tileMask;
     } else if (!enablePickMode && enableTexture) {
         /* Using the first texture coordinate, modulate the RGBA color with the 2D texture's RGBA color. Finally,
            modulate by the tile mask to suppress fragments outside the surface tile. */
-        gl_FragColor = color * texture2D(texSampler, texCoord[0]) * tileMask;
+        gl_FragColor = color * texture2D(texSampler, texCoord) * tileMask;
     } else {
         /* Modulate the RGBA color by the tile mask to suppress fragments outside the surface tile. */
         gl_FragColor = color * tileMask;

worldwind/src/main/res/raw/gov_nasa_worldwind_surfacetextureprogram_vert.glsl

@@ -12,7 +12,8 @@ uniform mat3 texCoordMatrix[2];
 attribute vec4 vertexPoint;
 attribute vec2 vertexTexCoord;
 
-varying vec2 texCoord[2];
+varying vec2 texCoord;
+varying vec2 tileCoord;
 
 void main() {
     /* Transform the vertex position by the modelview-projection matrix. */
@@ -21,7 +22,7 @@ void main() {
     /* Transform the vertex tex coord by the tex coord matrices. */
     if (enableTexture) {
         vec3 texCoord3 = vec3(vertexTexCoord, 1.0);
-        texCoord[0] = (texCoordMatrix[0] * texCoord3).st;
-        texCoord[1] = (texCoordMatrix[1] * texCoord3).st;
+        texCoord = (texCoordMatrix[0] * texCoord3).st;
+        tileCoord = (texCoordMatrix[1] * texCoord3).st;
     }
 }