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copied!<p>Your <code>glTexImage2D</code> <em>is correct</em>, so that's not the problem.</p> <p>I do need (when loading TGA files) to swap the color components. Try this:</p> <pre><code>typedef struct { unsigned char imageTypeCode; short int imageWidth; short int imageHeight; unsigned char bitCount; unsigned char *imageData; } TGAFILE; bool LoadTGAFile(char *filename, TGAFILE *tgaFile) { FILE *filePtr; unsigned char ucharBad; short int sintBad; long imageSize; int colorMode; unsigned char colorSwap; // Open the TGA file. filePtr = fopen(filename, "rb"); if (filePtr == NULL) { return false; } // Read the two first bytes we don't need. fread(&ucharBad, sizeof(unsigned char), 1, filePtr); fread(&ucharBad, sizeof(unsigned char), 1, filePtr); // Which type of image gets stored in imageTypeCode. fread(&tgaFile->imageTypeCode, sizeof(unsigned char), 1, filePtr); // For our purposes, the type code should be 2 (uncompressed RGB image) // or 3 (uncompressed black-and-white images). if (tgaFile->imageTypeCode != 2 && tgaFile->imageTypeCode != 3) { fclose(filePtr); return false; } // Read 13 bytes of data we don't need. fread(&sintBad, sizeof(short int), 1, filePtr); fread(&sintBad, sizeof(short int), 1, filePtr); fread(&ucharBad, sizeof(unsigned char), 1, filePtr); fread(&sintBad, sizeof(short int), 1, filePtr); fread(&sintBad, sizeof(short int), 1, filePtr); // Read the image's width and height. fread(&tgaFile->imageWidth, sizeof(short int), 1, filePtr); fread(&tgaFile->imageHeight, sizeof(short int), 1, filePtr); // Read the bit depth. fread(&tgaFile->bitCount, sizeof(unsigned char), 1, filePtr); // Read one byte of data we don't need. fread(&ucharBad, sizeof(unsigned char), 1, filePtr); // Color mode -> 3 = BGR, 4 = BGRA. colorMode = tgaFile->bitCount / 8; imageSize = tgaFile->imageWidth * tgaFile->imageHeight * colorMode; // Allocate memory for the image data. tgaFile->imageData = (unsigned char*)malloc(sizeof(unsigned char)*imageSize); // Read the image data. fread(tgaFile->imageData, sizeof(unsigned char), imageSize, filePtr); // Change from BGR to RGB so OpenGL can read the image data. for (int imageIdx = 0; imageIdx < imageSize; imageIdx += colorMode) { colorSwap = tgaFile->imageData[imageIdx]; tgaFile->imageData[imageIdx] = tgaFile->imageData[imageIdx + 2]; tgaFile->imageData[imageIdx + 2] = colorSwap; } fclose(filePtr); return true; } </code></pre>

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