Variable MEGA_VERTEX_SHADERConst
MEGA_VERTEX_SHADER: "\n out vec2 vUv;\n\n void main() {\n // Position is in NDC. Read the caps-aware uv attribute from the\n // fullscreen-triangle geometry — it encodes the backend-specific\n // Y orientation correction so the fragment samples the right row\n // of the source target on both WebGL2 and real WebGPU.\n vUv = uv;\n gl_Position = vec4(position.xy, 0.0, 1.0);\n }\n" = ...