Variable BLOOM_DOWNSAMPLE_FRAGMENT_SHADERConst
BLOOM_DOWNSAMPLE_FRAGMENT_SHADER: "\n precision highp float;\n in vec2 vUv;\n out vec4 fragColor;\n\n uniform sampler2D uInput;\n uniform vec2 uTexelSize;\n\n void main() {\n vec2 d = uTexelSize * 0.5;\n vec3 s0 = texture(uInput, vUv + d * vec2(-1.0, -1.0)).rgb;\n vec3 s1 = texture(uInput, vUv + d * vec2( 1.0, -1.0)).rgb;\n vec3 s2 = texture(uInput, vUv + d * vec2(-1.0, 1.0)).rgb;\n vec3 s3 = texture(uInput, vUv + d * vec2( 1.0, 1.0)).rgb;\n fragColor = vec4((s0 + s1 + s2 + s3) * 0.25, 1.0);\n }\n" = ...
Plain 2× box downsample (no threshold).