VBO-related optimizations and improvements (#14395)

client/shaders/cloud_shader/opengl_vertex.glsl

@@ -0,0 +1,21 @@
+uniform vec4 emissiveColor;
+
+varying lowp vec4 varColor;
+
+varying vec3 eyeVec;
+
+void main(void)
+{
+	gl_Position = mWorldViewProj * inVertexPosition;
+
+#ifdef GL_ES
+	vec4 color = inVertexColor.bgra;
+#else
+	vec4 color = inVertexColor;
+#endif
+
+	color *= emissiveColor;
+	varColor = color;
+
+	eyeVec = -(mWorldView * inVertexPosition).xyz;
+}