GLUSboolean GLUSAPIENTRY glusWindowRun(GLUSvoid)
{
GLUSboolean run = GLUS_TRUE;
if (!glusWindowStartup())
{
return GLUS_FALSE;
}
while (run)
{
if (glusWindowIsRecording())
{
run = glusWindowLoopDoRecording();
}
else
{
run = glusWindowLoop();
}
}
glusWindowShutdown();
return GLUS_TRUE; // Exit The Program
}
GLUSboolean GLUSAPIENTRY glusWindowStartup(GLUSvoid)
{
// Init Engine
if (glusInit)
{
if (!glusInit())
{
glusWindowShutdown();
return GLUS_FALSE; // Exit The Program
}
}
g_initdone = GLUS_TRUE;
// Do the first reshape
if (glusReshape)
{
glusReshape(g_width, g_height);
}
return GLUS_TRUE;
}
int main(int argc, char* argv[])
{
GLUSchar* output;
GLUSchar* extension;
GLUSchar fileType[MAX_FILETYPE_LENGTH];
GLUSchar buffer[MAX_FILENAME_LENGTH];
GLUSint roughnessSamples;
GLUSuint exponent;
GLUSuint samples;
GLUSint i, k, m, o, p, q, ouputLength;
GLUSuint x = 0;
GLUSuint y = 0;
GLUSboolean isHDR = GLUS_FALSE;
GLUStgaimage tgaOutput[2];
GLUShdrimage hdrOutput[2];
GLUSboolean mipMap;
GLUSint length;
GLUSint lengthExponent;
GLUSint stride;
GLUSfloat offset, step, roughness;
GLUSfloat startVector[3] = { 1.0f, -1.0f, -1.0f };
GLUSfloat offsetVector[3];
GLUSfloat normalVector[3];
GLUSfloat* scanVectors;
GLUSfloat* colorBufferLambert;
GLUSfloat* colorBufferCookTorrance;
GLUSfloat matrix[9];
GLUStextfile computeSource;
GLUSprogram computeProgram;
GLUSuint localSize = 16;
GLUSuint textureLambert;
GLUSuint textureCookTorrance[MAX_ROUGHNESS];
GLUSuint scanVectorsSSBO;
GLUSint mLocation;
GLUSint samplesLocation;
GLUSint binaryFractionFactorLocation;
GLUSint roughnessLocation;
EGLint eglConfigAttributes[] = {
EGL_RED_SIZE, 8,
EGL_GREEN_SIZE, 8,
EGL_BLUE_SIZE, 8,
EGL_DEPTH_SIZE, 0,
EGL_STENCIL_SIZE, 0,
EGL_RENDERABLE_TYPE, EGL_OPENGL_BIT,
EGL_NONE
};
EGLint eglContextAttributes[] = {
EGL_CONTEXT_MAJOR_VERSION, 4,
EGL_CONTEXT_MINOR_VERSION, 3,
EGL_CONTEXT_OPENGL_FORWARD_COMPATIBLE, EGL_TRUE,
EGL_CONTEXT_OPENGL_PROFILE_MASK, EGL_CONTEXT_OPENGL_CORE_PROFILE_BIT,
EGL_NONE
};
if (argc != 12)
{
printf("Usage: PreFilterCubeMap.exe [Pos X] [Neg X] [Pos Y] [Neg Y] [Pos Z] [Neg Z] [Output] [Roughness] [Samples 2^m] [Length 2^n] [As MipMap]\n");
return -1;
}
//
output = argv[7];
ouputLength = strlen(output);
if (ouputLength >= MAX_FILENAME_LENGTH - (MAX_FILETYPE_LENGTH - 1) - SIDE_NAMING_LENGTH - ROUGHNESS_NAMING_LENGTH - TYPE_NAMING_LENGTH)
{
printf("Error: Output filename too long.\n");
return -1;
}
roughnessSamples = atoi(argv[8]);
if (roughnessSamples < 2 || roughnessSamples >= MAX_ROUGHNESS)
{
printf("Error: Invalid roughness value.\n");
return -1;
}
exponent = (GLUSuint)atoi(argv[9]);
if (exponent > 16)
{
printf("Error: Invalid samples value.\n");
return -1;
}
samples = 1 << exponent;
lengthExponent = (GLUSuint)atoi(argv[10]);
if (lengthExponent > 16)
{
printf("Error: Invalid length value.\n");
return -1;
}
length = 1 << lengthExponent;
mipMap = (GLUSuint)atoi(argv[11]) != 0;
if (mipMap && roughnessSamples - 1 > lengthExponent)
{
printf("Error: Can not do mip mapping with given roughness and length.\n");
return -1;
}
//
extension = strrchr(argv[1], '.');
if (extension == 0)
{
printf("Error: No file type found.\n");
return -1;
}
if (strlen(extension) != MAX_FILETYPE_LENGTH - 1)
{
printf("Error: Invalid file type.\n");
return -1;
}
// Copy includes NULL terminating character.
for (i = 0; i < MAX_FILETYPE_LENGTH ; i++)
{
fileType[i] = tolower(extension[i]);
}
stride = 1;
printf("Loading texture cube maps ... ");
if (strcmp(fileType, ".tga") == 0)
{
//
for (i = 0; i < 6; i++)
{
if (!glusImageLoadTga(argv[1 + i], &g_tgaimage[i]))
{
printf("failed! TGA image could not be loaded.\n");
freeTgaImages(i);
return -1;
}
if (i > 0)
{
if (g_tgaimage[0].width != g_tgaimage[i].width || g_tgaimage[0].height != g_tgaimage[i].height)
{
printf("failed! TGA images do have different dimension.\n");
freeTgaImages(i + 1);
return -1;
}
}
else
{
if (g_tgaimage[0].width != g_tgaimage[i].height)
{
printf("failed! TGA images do have different dimension.\n");
freeTgaImages(1);
return -1;
}
}
}
if (g_tgaimage[0].format == GLUS_RGB)
{
stride = 3;
}
else if (g_tgaimage[0].format == GLUS_RGBA)
{
stride = 4;
}
//
tgaOutput[0] = g_tgaimage[0];
tgaOutput[0].width = length;
tgaOutput[0].height = length;
tgaOutput[0].data = (GLUSubyte*)malloc(length * length * stride * sizeof(GLUSubyte));
if (!tgaOutput[0].data)
{
printf("failed! TGA output image could not be created.\n");
freeTgaImages(6);
return -1;
}
tgaOutput[1] = g_tgaimage[0];
tgaOutput[1].width = length;
tgaOutput[1].height = length;
tgaOutput[1].data = (GLUSubyte*)malloc(length * length * stride * sizeof(GLUSubyte));
if (!tgaOutput[1].data)
{
printf("failed! TGA output image could not be created.\n");
freeTgaImages(6);
glusImageDestroyTga(&tgaOutput[0]);
return -1;
}
}
else if (strcmp(fileType, ".hdr") == 0)
{
isHDR = GLUS_TRUE;
for (i = 0; i < 6; i++)
{
if (!glusImageLoadHdr(argv[1 + i], &g_hdrimage[i]))
{
printf("failed! HDR image could not be loaded.\n");
freeHdrImages(i);
return -1;
}
if (i > 0)
{
if (g_hdrimage[0].width != g_hdrimage[i].width || g_hdrimage[0].height != g_hdrimage[i].height)
{
printf("failed! HDR images do have different dimension.\n");
freeHdrImages(i + 1);
return -1;
}
}
else
{
if (g_hdrimage[0].width != g_hdrimage[i].height)
{
printf("failed! HDR images do have different dimension.\n");
freeHdrImages(1);
return -1;
}
}
}
stride = 3;
//
hdrOutput[0] = g_hdrimage[0];
hdrOutput[0].width = length;
hdrOutput[0].height = length;
hdrOutput[0].data = (GLUSfloat*)malloc(length * length * stride * sizeof(GLUSfloat));
if (!hdrOutput[0].data)
{
printf("failed! HDR output image could not be created.\n");
freeHdrImages(6);
return -1;
}
hdrOutput[1] = g_hdrimage[0];
hdrOutput[1].width = length;
hdrOutput[1].height = length;
hdrOutput[1].data = (GLUSfloat*)malloc(length * length * stride * sizeof(GLUSfloat));
if (!hdrOutput[1].data)
{
printf("failed! HDR output image could not be created.\n");
freeHdrImages(6);
glusImageDestroyHdr(&hdrOutput[1]);
return -1;
}
}
else
{
printf("failed. Unknown file type.\n");
return -1;
}
printf("completed!\n");
// Contains the vectors to scan and generate one side of the pre-filtered cube map.
scanVectors = (GLUSfloat*)malloc(length * length * (3 + 1) * sizeof(GLUSfloat));
if (!scanVectors)
{
printf("Error: Scan scanVectors could not be created.\n");
freeHdrImages(6);
return -1;
}
// Color buffer needed to gather the pixels from the texture.
colorBufferLambert = (GLUSfloat*)malloc(length * length * 4 * sizeof(GLUSfloat));
if (!colorBufferLambert)
{
printf("Error: Color buffer could not be created.\n");
freeHdrImages(6);
free(scanVectors);
return -1;
}
// Color buffer needed to gather the pixels from the texture.
colorBufferCookTorrance = (GLUSfloat*)malloc(length * length * 4 * sizeof(GLUSfloat));
if (!colorBufferCookTorrance)
{
printf("Error: Color buffer could not be created.\n");
freeHdrImages(6);
free(scanVectors);
free(colorBufferLambert);
return -1;
}
//
// Initialize OpenGL, as it is needed for the compute shader.
//
if (!glusWindowCreate("GLUS Example Window", 512, 512, GLUS_FALSE, GLUS_FALSE, eglConfigAttributes, eglContextAttributes))
{
printf("Could not create window!\n");
return -1;
}
if (!glusWindowStartup())
{
return -1;
}
//
// Compute shader for pre-filtering.
//
glusFileLoadText("../PreFilterCubeMap/shader/prefilter.comp.glsl", &computeSource);
glusProgramBuildComputeFromSource(&computeProgram, (const GLchar**)&computeSource.text);
glusFileDestroyText(&computeSource);
//
mLocation = glGetUniformLocation(computeProgram.program, "u_m");
samplesLocation = glGetUniformLocation(computeProgram.program, "u_samples");
binaryFractionFactorLocation = glGetUniformLocation(computeProgram.program, "u_binaryFractionFactor");
roughnessLocation = glGetUniformLocation(computeProgram.program, "u_roughness");
//
glUseProgram(computeProgram.program);
//
//
//
// Create cube maps
if (isHDR)
{
createHdrCubeMap();
freeHdrImages(6);
}
else
{
createTgaCubeMap();
freeTgaImages(6);
}
// Prepare texture, where the pre-filtered image is stored: Lambert
glGenTextures(1, &textureLambert);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, textureLambert);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, length, length, 0, GL_RGBA, GL_FLOAT, 0);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
// see binding = 1 in the shader
glBindImageTexture(1, textureLambert, 0, GL_FALSE, 0, GL_WRITE_ONLY, GL_RGBA32F);
glPixelStorei(GL_PACK_ALIGNMENT, 1);
//
if (mipMap)
{
// Prepare texture, where the pre-filtered image is stored: Cook-Torrance
glGenTextures(roughnessSamples, textureCookTorrance);
for (i = 0; i < roughnessSamples; i++)
{
glActiveTexture(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, textureCookTorrance[i]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, length, length, 0, GL_RGBA, GL_FLOAT, 0);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
length /= 2;
}
length = 1 << lengthExponent;
}
else
{
// Prepare texture, where the pre-filtered image is stored: Cook-Torrance
glGenTextures(1, textureCookTorrance);
glActiveTexture(GL_TEXTURE2);
glBindTexture(GL_TEXTURE_2D, textureCookTorrance[0]);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA32F, length, length, 0, GL_RGBA, GL_FLOAT, 0);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
// see binding = 2 in the shader
glBindImageTexture(2, textureCookTorrance[0], 0, GL_FALSE, 0, GL_WRITE_ONLY, GL_RGBA32F);
glPixelStorei(GL_PACK_ALIGNMENT, 1);
}
//
//
//
step = 2.0f / (GLUSfloat)length;
offset = step * 0.5f;
// Prepare save name.
strcpy(buffer, output);
buffer[ouputLength + 0] = '_';
buffer[ouputLength + 4] = '_';
buffer[ouputLength + 6] = '_';
buffer[ouputLength + 9] = '_';
for (i = ouputLength + SIDE_NAMING_LENGTH + ROUGHNESS_NAMING_LENGTH + TYPE_NAMING_LENGTH; i < ouputLength + SIDE_NAMING_LENGTH + ROUGHNESS_NAMING_LENGTH + TYPE_NAMING_LENGTH + MAX_FILETYPE_LENGTH; i++)
{
buffer[i] = fileType[i - (ouputLength + SIDE_NAMING_LENGTH + ROUGHNESS_NAMING_LENGTH + TYPE_NAMING_LENGTH)];
}
//
// Setup scan vectors buffer for compute shader.
glGenBuffers(1, &scanVectorsSSBO);
glBindBuffer(GL_SHADER_STORAGE_BUFFER, scanVectorsSSBO);
glBufferData(GL_SHADER_STORAGE_BUFFER, length * length * (3 + 1) * sizeof(GLfloat), 0, GL_DYNAMIC_DRAW);
// see binding = 3 in the shader
glBindBufferBase(GL_SHADER_STORAGE_BUFFER, 3, scanVectorsSSBO);
// Setup m and samples for compute shader.
glUniform1ui(mLocation, exponent);
glUniform1ui(samplesLocation, samples);
// Results are in range [0.0 1.0] and not [0.0, 1.0[.
glUniform1f(binaryFractionFactorLocation, 1.0f / (powf(2.0f, (GLfloat)exponent) - 1.0f));
printf("Generating pre filtered cube maps ...\n");
for (i = 0; i < 6; i++)
{
printf("Side: %d\n", i);
switch (i)
{
case 0:
// Positive X
glusMatrix3x3Identityf(matrix);
buffer[ouputLength + 1] = 'P';
buffer[ouputLength + 2] = 'O';
buffer[ouputLength + 3] = 'S';
buffer[ouputLength + 5] = 'X';
break;
case 1:
// Negative X
glusMatrix3x3Identityf(matrix);
glusMatrix3x3RotateRyf(matrix, 180.0f);
buffer[ouputLength + 1] = 'N';
buffer[ouputLength + 2] = 'E';
buffer[ouputLength + 3] = 'G';
buffer[ouputLength + 5] = 'X';
break;
case 2:
// Positive Y
glusMatrix3x3Identityf(matrix);
glusMatrix3x3RotateRxf(matrix, 90.0f);
glusMatrix3x3RotateRyf(matrix, 90.0f);
buffer[ouputLength + 1] = 'P';
buffer[ouputLength + 2] = 'O';
buffer[ouputLength + 3] = 'S';
buffer[ouputLength + 5] = 'Y';
break;
case 3:
// Negative Y
glusMatrix3x3Identityf(matrix);
glusMatrix3x3RotateRxf(matrix, -90.0f);
glusMatrix3x3RotateRyf(matrix, 90.0f);
buffer[ouputLength + 1] = 'N';
buffer[ouputLength + 2] = 'E';
buffer[ouputLength + 3] = 'G';
buffer[ouputLength + 5] = 'Y';
break;
case 4:
// Positive Z
glusMatrix3x3Identityf(matrix);
glusMatrix3x3RotateRyf(matrix, -90.0f);
buffer[ouputLength + 1] = 'P';
buffer[ouputLength + 2] = 'O';
buffer[ouputLength + 3] = 'S';
buffer[ouputLength + 5] = 'Z';
break;
case 5:
// Negative Z
glusMatrix3x3Identityf(matrix);
glusMatrix3x3RotateRyf(matrix, 90.0f);
buffer[ouputLength + 1] = 'N';
buffer[ouputLength + 2] = 'E';
buffer[ouputLength + 3] = 'G';
buffer[ouputLength + 5] = 'Z';
break;
}
if (!mipMap)
{
// Generate scan vectors
for (k = 0; k < length; k++)
{
for (m = 0; m < length; m++)
{
offsetVector[0] = 0.0f;
offsetVector[1] = offset + step * (GLUSfloat)k;
offsetVector[2] = offset + step * (GLUSfloat)m;
glusVector3AddVector3f(normalVector, startVector, offsetVector);
glusVector3Normalizef(normalVector);
glusMatrix3x3MultiplyVector3f(&scanVectors[k * length * (3 + 1) + m * (3 + 1)], matrix, normalVector);
}
}
// Upload scan vectors for each side.
glBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, length * length * (3 + 1) * sizeof(GLfloat), scanVectors);
}
// For all roughness levels
for (k = 0; k < roughnessSamples; k++)
{
if (mipMap)
{
if (isHDR)
{
hdrOutput[1].width = length;
hdrOutput[1].height = length;
}
else
{
tgaOutput[1].width = length;
tgaOutput[1].height = length;
}
step = 2.0f / (GLUSfloat)length;
offset = step * 0.5f;
// Generate scan vectors
for (m = 0; m < length; m++)
{
for (o = 0; o < length; o++)
{
offsetVector[0] = 0.0f;
offsetVector[1] = offset + step * (GLUSfloat)m;
offsetVector[2] = offset + step * (GLUSfloat)o;
glusVector3AddVector3f(normalVector, startVector, offsetVector);
glusVector3Normalizef(normalVector);
glusMatrix3x3MultiplyVector3f(&scanVectors[m * length * (3 + 1) + o * (3 + 1)], matrix, normalVector);
}
}
// Upload scan vectors for each side.
glBufferSubData(GL_SHADER_STORAGE_BUFFER, 0, length * length * (3 + 1) * sizeof(GLfloat), scanVectors);
}
// Calculate roughness ...
roughness = (GLUSfloat)k * 1.0f / (GLUSfloat)(roughnessSamples - 1);
printf("Roughness: %f\n", roughness);
// ... and set it up for compute shader.
glUniform1f(roughnessLocation, roughness);
if (mipMap)
{
// see binding = 2 in the shader
glBindImageTexture(2, textureCookTorrance[k], 0, GL_FALSE, 0, GL_WRITE_ONLY, GL_RGBA32F);
glPixelStorei(GL_PACK_ALIGNMENT, 1);
}
// Run the compute shader, which is doing the pre-filtering.
glDispatchCompute(length / localSize, length / localSize, 1);
glActiveTexture(GL_TEXTURE1);
glBindTexture(GL_TEXTURE_2D, textureLambert);
if (roughness == 0.0f)
{
// Compute shader stores result in given texture.
glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_FLOAT, colorBufferLambert);
}
glActiveTexture(GL_TEXTURE2);
if (mipMap)
{
glBindTexture(GL_TEXTURE_2D, textureCookTorrance[k]);
}
else
{
glBindTexture(GL_TEXTURE_2D, textureCookTorrance[0]);
}
// Compute shader stores result in given texture.
glGetTexImage(GL_TEXTURE_2D, 0, GL_RGBA, GL_FLOAT, colorBufferCookTorrance);
// Resolve
for (p = 0; p < length; p++)
{
for (q = 0; q < length; q++)
{
// Some of the textures need to be stored flipped and mirrored down.
switch (i)
{
case 0:
case 1:
case 4:
case 5:
// Positive X
// Negative X
// Positive Z
// Negative Z
x = length - 1 - q;
y = length - 1 - p;
break;
case 2:
case 3:
// Positive Y
// Negative Y
x = q;
y = p;
break;
}
for (o = 0; o < stride; o++)
{
if (isHDR)
{
if (roughness == 0.0f)
{
hdrOutput[0].data[p * length * stride + q * stride + o] = colorBufferLambert[y * length * 4 + x * 4 + o];
}
hdrOutput[1].data[p * length * stride + q * stride + o] = colorBufferCookTorrance[y * length * 4 + x * 4 + o];
}
else
{
if (roughness == 0.0f)
{
tgaOutput[0].data[p * length * stride + q * stride + o] = (GLUSubyte)glusMathClampf(colorBufferLambert[y * length * 4 + x * 4 + o] * 255.0f, 0.0f, 255.0f);
}
tgaOutput[1].data[p * length * stride + q * stride + o] = (GLUSubyte)glusMathClampf(colorBufferCookTorrance[y * length * 4 + x * 4 + o] * 255.0f, 0.0f, 255.0f);
}
}
}
}
// Construct save name depending on roughness level.
buffer[ouputLength + 7] = '0' + (k / 10);
buffer[ouputLength + 8] = '0' + (k % 10);
if (isHDR)
{
if (roughness == 0.0f)
{
buffer[ouputLength + 10] = 'd';
glusImageSaveHdr(buffer, &hdrOutput[0]);
}
buffer[ouputLength + 10] = 's';
glusImageSaveHdr(buffer, &hdrOutput[1]);
}
else
{
if (roughness == 0.0f)
{
buffer[ouputLength + 10] = 'd';
glusImageSaveTga(buffer, &tgaOutput[0]);
}
buffer[ouputLength + 10] = 's';
glusImageSaveTga(buffer, &tgaOutput[1]);
}
if (mipMap)
{
length /= 2;
}
}
if (mipMap)
{
length = 1 << lengthExponent;
}
}
printf("completed!\n");
//
// Freeing resources
//
free(scanVectors);
free(colorBufferLambert);
free(colorBufferCookTorrance);
glusProgramDestroy(&computeProgram);
glBindTexture(GL_TEXTURE_CUBE_MAP, 0);
if (g_cubemap)
{
glDeleteTextures(1, &g_cubemap);
g_cubemap = 0;
}
glBindTexture(GL_TEXTURE_2D, 0);
if (textureLambert)
{
glDeleteTextures(1, &textureLambert);
textureLambert = 0;
}
if (!mipMap)
{
if (textureCookTorrance[0])
{
glDeleteTextures(1, textureCookTorrance);
textureCookTorrance[0] = 0;
}
}
else
{
glDeleteTextures(roughnessSamples, textureCookTorrance);
}
if (isHDR)
{
glusImageDestroyHdr(&hdrOutput[0]);
glusImageDestroyHdr(&hdrOutput[1]);
}
else
{
glusImageDestroyTga(&tgaOutput[0]);
glusImageDestroyTga(&tgaOutput[1]);
}
glBindBuffer(GL_SHADER_STORAGE_BUFFER, 0);
if (scanVectorsSSBO)
{
glDeleteBuffers(1, &scanVectorsSSBO);
scanVectorsSSBO = 0;
}
//
// Shutdown OpenGL.
//
glusWindowShutdown();
return 0;
}