// glsl / C++ compatible source as interface for FrustrumGrid#if defined(Q_OS_LINUX)#define float_exp2 exp2f#else#define float_exp2 exp2#endif #ifdef __cplusplus#   define _MIN glm::min#   define _ABS(x) (int)fabsf(x)#else#   define _MIN min#   define _ABS abs#endif float frustumGrid_depthRampGridToVolume(float ngrid) {   //  return ngrid;   // return sqrt(ngrid);    return float_exp2(ngrid) - 1.0f;}float frustumGrid_depthRampInverseVolumeToGrid(float nvolume) {   //   return nvolume;   // return nvolume * nvolume;    return log2(nvolume + 1.0f);} vec3 frustumGrid_gridToVolume(vec3 pos, ivec3 dims) {    vec3 gridScale = vec3(1.0f) / vec3(dims);    vec3 volumePos = pos * gridScale;    volumePos.z = frustumGrid_depthRampGridToVolume(volumePos.z);    return volumePos;}  float frustumGrid_volumeToGridDepth(float vposZ, ivec3 dims) {    return frustumGrid_depthRampInverseVolumeToGrid(vposZ) * float(dims.z);} vec3 frustumGrid_volumeToGrid(vec3 vpos, ivec3 dims) {    vec3 gridPos = vec3(vpos.x, vpos.y, frustumGrid_depthRampInverseVolumeToGrid(vpos.z)) * vec3(dims);    return gridPos;}  vec4 frustumGrid_volumeToClip(vec3 vpos, float rangeNear, float rangeFar) {    vec3 ndcPos = vec3(-1.0f + 2.0f * vpos.x, -1.0f + 2.0f * vpos.y, vpos.z);    float depth = rangeNear * (1.0f - ndcPos.z) + rangeFar * (ndcPos.z);    vec4 clipPos = vec4(ndcPos.x * depth, ndcPos.y * depth, 1.0f, depth);    return clipPos;} vec3 frustumGrid_clipToEye(vec4 clipPos, mat4 projection) {    return vec3(        (clipPos.x + projection[2][0] * clipPos.w) / projection[0][0],        (clipPos.y + projection[2][1] * clipPos.w) / projection[1][1],        -clipPos.w        //, (clipPos.z - projection[3][3] * clipPos.w) / projection[3][2]        );} vec3 frustumGrid_volumeToEye(vec3 vpos, mat4 projection, float rangeNear, float rangeFar) {    return frustumGrid_clipToEye(frustumGrid_volumeToClip(vpos, rangeNear, rangeFar), projection);} float frustumGrid_eyeToVolumeDepth(float eposZ, float rangeNear, float rangeFar) {    return (-eposZ - rangeNear) / (rangeFar - rangeNear);} vec3 frustumGrid_eyeToVolume(vec3 epos, mat4 projection, float rangeNear, float rangeFar) {    vec4 clipPos = vec4(epos.x * projection[0][0] + epos.z * projection[2][0],        epos.y * projection[1][1] + epos.z * projection[2][1],        epos.z * projection[2][2] + projection[2][3],        -epos.z);    vec4 ndcPos = clipPos / clipPos.w;     vec3 volumePos = vec3(0.5f * (ndcPos.x + 1.0f), 0.5f * (ndcPos.y + 1.0f), (clipPos.w - rangeNear) / (rangeFar - rangeNear));    return volumePos;}   int frustumGrid_numClusters() {    return frustumGrid.dims.x * frustumGrid.dims.y * (frustumGrid.dims.z + 1);} int frustumGrid_clusterToIndex(ivec3 pos) {    return pos.x + (pos.y + pos.z * frustumGrid.dims.y) * frustumGrid.dims.x;}ivec3 frustumGrid_indexToCluster(int index) {    ivec3 summedDims = ivec3(frustumGrid.dims.x * frustumGrid.dims.y, frustumGrid.dims.x, 1);    int layer = index / summedDims.x;    int offsetInLayer = index % summedDims.x;    ivec3 clusterPos = ivec3(offsetInLayer % summedDims.y, offsetInLayer / summedDims.y, layer);    return clusterPos;} vec3 frustumGrid_clusterPosToEye(vec3 clusterPos) {    vec3 cvpos = clusterPos;    vec3 volumePos = frustumGrid_gridToVolume(cvpos, frustumGrid.dims);    vec3 eyePos = frustumGrid_volumeToEye(volumePos, frustumGrid.eyeToGridProj, frustumGrid.rangeNear, frustumGrid.rangeFar);    return eyePos;} vec3 frustumGrid_clusterPosToEye(ivec3 clusterPos, vec3 offset) {    vec3 cvpos = vec3(clusterPos) + offset;    return frustumGrid_clusterPosToEye(cvpos);} int frustumGrid_eyeDepthToClusterLayer(float eyeZ) {    if ((eyeZ > -frustumGrid.frustumNear) || (eyeZ < -frustumGrid.frustumFar)) {        return -2;    }     if (eyeZ > -frustumGrid.rangeNear) {        return -1;    }     float volumeZ = frustumGrid_eyeToVolumeDepth(eyeZ, frustumGrid.rangeNear, frustumGrid.rangeFar);     int gridZ = int(frustumGrid_volumeToGridDepth(volumeZ, frustumGrid.dims));     return _MIN(gridZ, frustumGrid.dims.z);} ivec3 frustumGrid_eyeToClusterPos(vec3 eyePos) {     // make sure the frontEyePos is always in the front to eval the grid pos correctly    vec3 frontEyePos = eyePos;    frontEyePos.z = -_ABS(eyePos.z);    vec3 volumePos = frustumGrid_eyeToVolume(frontEyePos, frustumGrid.eyeToGridProj, frustumGrid.rangeNear, frustumGrid.rangeFar);      vec3 gridPos = frustumGrid_volumeToGrid(volumePos, frustumGrid.dims);    gridPos.z = _MIN(gridPos.z, float(frustumGrid.dims.z));     ivec3 igridPos = ivec3(floor(gridPos));     if ((eyePos.z > -frustumGrid.frustumNear) || (eyePos.z < -frustumGrid.frustumFar)) {        return ivec3(igridPos.x, igridPos.y, - 2);    }     if (eyePos.z > -frustumGrid.rangeNear) {        return ivec3(igridPos.x, igridPos.y, -1);    }     return igridPos;}  int frustumGrid_eyeToClusterDirH(vec3 eyeDir) {    if (eyeDir.z >= 0.0f) {        return int(eyeDir.x > 0.0f) * (frustumGrid.dims.x + 1) - 1;    }     float eyeDepth = -eyeDir.z;    float nclipDir = eyeDir.x / eyeDepth;    float ndcDir = nclipDir * frustumGrid.eyeToGridProj[0][0] - frustumGrid.eyeToGridProj[2][0];    float volumeDir = 0.5f * (ndcDir + 1.0f);    float gridPos = volumeDir * float(frustumGrid.dims.x);     return int(gridPos);} int frustumGrid_eyeToClusterDirV(vec3 eyeDir) {    if (eyeDir.z >= 0.0f) {        return int(eyeDir.y > 0.0f) * (frustumGrid.dims.y + 1) - 1;    }     float eyeDepth = -eyeDir.z;    float nclipDir = eyeDir.y / eyeDepth;    float ndcDir = nclipDir * frustumGrid.eyeToGridProj[1][1] - frustumGrid.eyeToGridProj[2][1];    float volumeDir = 0.5f * (ndcDir + 1.0f);    float gridPos = volumeDir * float(frustumGrid.dims.y);     return int(gridPos);} ivec2 frustumGrid_eyeToClusterDir(vec3 eyeDir) {    return ivec2(frustumGrid_eyeToClusterDirH(eyeDir), frustumGrid_eyeToClusterDirV(eyeDir));} vec4 frustumGrid_eyeToWorld(vec4 eyePos) {    return frustumGrid.eyeToWorldMat * eyePos;} vec4 frustumGrid_worldToEye(vec4 worldPos) {    return frustumGrid.worldToEyeMat * worldPos;}       // <@if 1@>    // Trigger Scribe include     // <@endif@> <!def that !> End C++ compatible