Drawable Renderer (#1570), rework attributes for fill drawables

shaders/drawable.fill.fragment.glsl

@@ -1,10 +1,12 @@
-layout (std140) uniform BackgroundLayerUBO {
-    vec4 u_color;
-    float u_opacity;
-};
+#pragma mapbox: define highp vec4 color
+#pragma mapbox: define lowp float opacity
 
 void main() {
-    fragColor = u_color * u_opacity;
+    #pragma mapbox: initialize highp vec4 color
+    #pragma mapbox: initialize lowp float opacity
+
+    fragColor = color * opacity;
+
 #ifdef OVERDRAW_INSPECTOR
     fragColor = vec4(1.0);
 #endif

shaders/drawable.fill.vertex.glsl

@@ -1,8 +1,15 @@
 layout (location = 0) in vec2 a_pos;
+
 layout (std140) uniform DrawableUBO {
     mat4 u_matrix;
 };
 
+#pragma mapbox: define highp vec4 color
+#pragma mapbox: define lowp float opacity
+
 void main() {
+    #pragma mapbox: initialize highp vec4 color
+    #pragma mapbox: initialize lowp float opacity
+
     gl_Position = u_matrix * vec4(a_pos, 0, 1);
 }

shaders/manifest.json

@@ -11,7 +11,7 @@
         "header": "drawable_fill",
         "glsl_vert": "drawable.fill.vertex.glsl",
         "glsl_frag": "drawable.fill.fragment.glsl",
-        "uses_ubos": true
+        "uses_ubos": false 
     },
 
     {
@@ -176,4 +176,4 @@
         "glsl_vert": "symbol_text_and_icon.vertex.glsl",
         "glsl_frag": "symbol_text_and_icon.fragment.glsl"
     }
-]
+]