cocos-creator-template/assets/chunks/builtin/functionalities/probe.chunk

#include <builtin/uniforms/cc-local>
vec4 GetTexData(sampler2D dataMap, float dataMapWidth, float x, float uv_y)
{
  return vec4(
      decode32(texture(dataMap, vec2(((x + 0.5)/dataMapWidth), uv_y))),
      decode32(texture(dataMap, vec2(((x + 1.5)/dataMapWidth), uv_y))),
      decode32(texture(dataMap, vec2(((x + 2.5)/dataMapWidth), uv_y))),
      decode32(texture(dataMap, vec2(((x + 3.5)/dataMapWidth), uv_y)))
    );
}
void GetPlanarReflectionProbeData(out vec4 plane, out float planarReflectionDepthScale, out float mipCount, float probeId)
{
    #if USE_INSTANCING
      float uv_y = (probeId + 0.5) / cc_probeInfo.x; //align to texel center
      float dataMapWidth = 12.0;
      vec4 texData1 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 0.0, uv_y);
      vec4 texData2 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 4.0, uv_y);
      plane.xyz = texData1.xyz;
      plane.w = texData2.x;
      planarReflectionDepthScale = texData2.y;
      mipCount = texData2.z;
    #else
      plane = cc_reflectionProbeData1;
      planarReflectionDepthScale = cc_reflectionProbeData2.x;
      mipCount = cc_reflectionProbeData2.w;
    #endif
}

void GetCubeReflectionProbeData(out vec3 centerPos, out vec3 boxHalfSize, out float mipCount, float probeId)
{
    #if USE_INSTANCING
      float uv_y = (probeId + 0.5) / cc_probeInfo.x; //align to texel center
      float dataMapWidth = 12.0;
      vec4 texData1 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 0.0, uv_y);
      vec4 texData2 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 4.0, uv_y);
      vec4 texData3 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 8.0, uv_y);
      centerPos = texData1.xyz;
      boxHalfSize = texData2.xyz;
      mipCount = texData3.x;
    #else
      centerPos = cc_reflectionProbeData1.xyz;
      boxHalfSize = cc_reflectionProbeData2.xyz;
      mipCount = cc_reflectionProbeData2.w;
    #endif
    RESTORE_REFLECTION_PROBE_MIP_COUNT(mipCount);
}

bool isReflectProbeUsingRGBE(float probeId)
{
  #if USE_INSTANCING
      float uv_y = (probeId + 0.5) / cc_probeInfo.x; //align to texel center
      float dataMapWidth = 12.0;
      vec4 texData3 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 8.0, uv_y);
      return IS_REFLECTION_PROBE_USE_RGBE(texData3.x);
  #else
    return IS_REFLECTION_PROBE_USE_RGBE(cc_reflectionProbeData2.w);
  #endif
}

bool isBlendReflectProbeUsingRGBE(float probeId)
{
  #if USE_INSTANCING
      float uv_y = (probeId + 0.5) / cc_probeInfo.x; //align to texel center
      float dataMapWidth = 12.0;
      vec4 texData3 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 8.0, uv_y);
      return IS_REFLECTION_PROBE_USE_RGBE(texData3.x);
  #else
    return IS_REFLECTION_PROBE_USE_RGBE(cc_reflectionProbeBlendData2.w);
  #endif
}

void GetBlendCubeReflectionProbeData(out vec3 centerPos, out vec3 boxHalfSize, out float mipCount, float probeId)
{
    #if USE_INSTANCING
      float uv_y = (probeId + 0.5) / cc_probeInfo.x; //align to texel center
      float dataMapWidth = 12.0;
      vec4 texData1 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 0.0, uv_y);
      vec4 texData2 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 4.0, uv_y);
      vec4 texData3 = GetTexData(cc_reflectionProbeDataMap, dataMapWidth, 8.0, uv_y);
      centerPos = texData1.xyz;
      boxHalfSize = texData2.xyz;
      mipCount = texData3.x;
    #else
      centerPos = cc_reflectionProbeBlendData1.xyz;
      boxHalfSize = cc_reflectionProbeBlendData2.xyz;
      mipCount = cc_reflectionProbeBlendData2.w;
    #endif
    RESTORE_REFLECTION_PROBE_MIP_COUNT(mipCount);
}