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Shane I Am

My Texture Class Wount Work! Please Help.

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Okay my texture class seems to not be working because after i attempt to use the data i load the texture seems to not exist. Here is the class... class TEXTURE { public: unsigned char *data; // Stored the bitmap data unsigned int ID; // the ID of the texture for binding unsigned int bbc; // color by bit count unsigned int height; // width of image unsigned int width; // height of image /////////////////////////////////////////////// // Prototypes /////////////////////////////////////////////// bool LoadTexture(char* fileName); //////////////////////////////////////////////// // Constructor/Deconstructor //////////////////////////////////////////////// TEXTURE() { data = NULL; ID = 1; bbc = 0; height = 0; width = 0; } ~TEXTURE() { // Lets free up the memory on texture destruction! Memory leaks suck! if(data != NULL) { glDeleteTextures(1, &ID); delete data; data = NULL; } } }; /////////////////////////////////////////////////////// // Function definitions /////////////////////////////////////////////////////// bool TEXTURE:: LoadTexture(char* fileName) { BITMAPFILEHEADER bitmapFileHeader; // bitmap file header int imageIdx = 0; // image index counter unsigned char tempRGB; // swap variable BITMAPINFOHEADER bitmapInfoHeader; // bitmap info header data = NULL; ///////////////////////////////////////////////////////////// // Load the bitmap ///////////////////////////////////////////////////////////// // open filename in "read binary" mode FILE *filePtr = fopen(fileName, "rb"); if (filePtr == NULL) return false; // read the bitmap file header fread(&bitmapFileHeader, sizeof(BITMAPFILEHEADER), 1, filePtr); // verify that this is a bitmap by checking for the universal bitmap id if (bitmapFileHeader.bfType != BITMAP_ID) { fclose(filePtr); return false; } // read the bitmap information header fread(&bitmapInfoHeader, sizeof(BITMAPINFOHEADER), 1, filePtr); // move file pointer to beginning of bitmap data fseek(filePtr, bitmapFileHeader.bfOffBits, SEEK_SET); // allocate enough memory for the bitmap image data data = new unsigned char [bitmapInfoHeader.biSizeImage]; // verify memory allocation if (!data) { free(data); fclose(filePtr); return false; } // read in the bitmap image data fread(data, 1, bitmapInfoHeader.biSizeImage, filePtr); // make sure bitmap image data was read if (data == NULL) { fclose(filePtr); return false; } // swap the R and B values to get RGB since the bitmap color format is in BGR for (imageIdx = 0; imageIdx < bitmapInfoHeader.biSizeImage; imageIdx+=3) { tempRGB = data[imageIdx]; data[imageIdx] = data[imageIdx + 2]; data[imageIdx + 2] = tempRGB; } // Get the width height and bbc width = bitmapInfoHeader.biWidth; height= bitmapInfoHeader.biWidth; bbc = bitmapInfoHeader.biBitCount; if(bbc==32) { bbc = GL_RGBA; } if(bbc==24) { bbc = GL_RGB; } ///////////////////////////////////////////////////////////// // Load the texture ///////////////////////////////////////////////////////////// glEnable(GL_TEXTURE_2D); // enable 2D texturing glGenTextures(1, &ID); // generate texture object glBindTexture(GL_TEXTURE_2D, ID); // enable our texture object glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR); glTexEnvi(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE); // generate the texture image glTexImage2D(GL_TEXTURE_2D, 0, bbc, width, height, 0, bbc, GL_UNSIGNED_BYTE, data); //gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGB, bitmapInfoHeader.biWidth, bitmapInfoHeader.biHeight, GL_RGB, GL_UNSIGNED_BYTE, data); // close the file and return the bitmap image data fclose(filePtr); return true; } ////////////////////////////////////////////////////////////// // End //////////////////////////////////////////////////////////////// So does anyone have any suggestions? I''ve been stuck on this for days! It always seems to not work when i put my code into a class for use

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Oh yeah here is a sample of how i use it....



glBindTexture(GL_TEXTURE_2D, shane.ID);
glTexCoord2f(0,0); glVertex3f(-1,-1,-5);
glTexCoord2f(1,0); glVertex3f(1,-1,-5);
glTexCoord2f(1,1); glVertex3f(1,1,-5);
glTexCoord2f(0,1); glVertex3f(-1,1,-5);


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Hello there,

First of all I need to say, I''m REALLY new to OpenGL and 3D programming! I have programming experience, but I only started studying these technologies 2 days ago.

Anyway, while I was looking at your code, I was wondering.... Didn''t you switch the width and height properties in your TEXTURE class definition?

unsigned int height; // width of image
unsigned int width; // height of image

And how about this piece of your loading code:

width = bitmapInfoHeader.biWidth;
height= bitmapInfoHeader.biWidth;

It assumed that the texture has equal sizes for width and height. Are they really?


Excuse me if I''m talking nonsense here. It just looks odd to me. I just wanted to point it out. I might be wrong.

Anyhow.. I hope I''m right (newby-luck hehe). And I hope you will find your solution to the problem..


We are only alive because we dream %*

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I read somewhere that with RGB bitmaps, the biSizeImage field can be zero. You might want to check if it is zero, and if so, store width * height * 3 in it.

Also, in your glTexImage2D call, you use bbc twice, containing the value GL_RGB or GL_RGBA. In the first instance, that field is the number of bytes per pixel, so 3 or 4. But in my implementation, GL_RGB is 0x1907 and GL_RGBA is 0x1908, so that could definitely be a problem. Try placing 3 in that field for an RGB image.

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Actually i did find those problems with my width/height but they didn''t help at all, thanks anyhow and that was a good observation.

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