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nick2price

OpenGL runtime error, maybe to do with glauz

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nick2price    120
When i compile my code, i get the error
1>skybox.cpp
1>c:\users\nick\desktop\university\graphics, c++\skybox\skybox\skybox.cpp(12) : warning C4996: 'fopen': This function or variable may be unsafe. Consider using fopen_s instead. To disable deprecation, use _CRT_SECURE_NO_WARNINGS. See online help for details.
1>        c:\program files\microsoft visual studio 9.0\vc\include\stdio.h(237) : see declaration of 'fopen'
1>c:\users\nick\desktop\university\graphics, c++\skybox\skybox\skybox.cpp(14) : error C2664: 'auxDIBImageLoadW' : cannot convert parameter 1 from 'char *' to 'LPCWSTR'
1>        Types pointed to are unrelated; conversion requires reinterpret_cast, C-style cast or function-style cast 
So i have added the glaux replacement code, found from this site i think, but i am unsure how to impliment it. I have added the bmp.cpp and bmp.h files to my project, but then i have this code which was there originally
bool skybox::Load_Texture(unsigned int & aTexture, char * fileName) {

	if(!fileName) return false;					//if no file name is given return

	FILE *aFile = NULL;
	AUX_RGBImagm *image_record = NULL;

	if((aFile = fopen(fileName, "rb")) == NULL) return false;

	image_record = auxDIBImageLoad(fileName);	//Function to load BMP

	if(!image_record) return false;				//check that BMP loaded

	glGenTextures(1, &aTexture);				//generates 1 texture name

	glPixelStorei (GL_UNPACK_ALIGNMENT, 1);		//sets how the pixels of the texture are stored

	glBindTexture(GL_TEXTURE_2D, aTexture);		//binds the name to the target
	

												//build prefiltered textures at different resolutions
	gluBuild2DMipmaps(GL_TEXTURE_2D, 3, image_record->sizeX, 
					  image_record->sizeY, GL_RGB, GL_UNSIGNED_BYTE, image_record->data);

												//give the texture its attributes
	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
	glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

	// Now we need to free the image data that we loaded since openGL stored it as a texture
	if (image_record) {							//if we stored data then free the memory
		if (image_record->data) {				//check if there is any data
			free(image_record->data);			//free the memory
		}
		free(image_record);						//free the image record
	}

	return true; //everything should have worked so return true
}
How would i change this to use the replacement glaux code? cheers

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V-man    813
Sounds like you have UNICODE enabled in your project.
auxDIBImageLoadW is the UNICODE version.
You should disabled it or just use
auxDIBImageLoadA (the ASCII version)

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nick2price    120
I am going to try an dget it working with the replacement code, but i have also remove unicode from my settings. So this is the code i got from nehe as a replacement to glaux

#include "stdafx.h"
#include <windows.h> // Header File For Windows - has structures for BMP format
#include <stdio.h> // Header File For Standard Input/Output
#include <stdlib.h>
#include "BMP.h"


AUX_RGBImageRec *auxDIBImageLoad(const char *FileName)
{
return new AUX_RGBImageRec(FileName);
}


void AUX_RGBImageRec::convertBGRtoRGB()
{
const DWORD BitmapLength = sizeX * sizeY * 3;
byte Temp; // not quick but it works
for(DWORD i=0; i< BitmapLength; i += 3)
{
Temp = data[i];
data[i] = data[i+2];
data[i+2] = Temp;
}
}

AUX_RGBImageRec::AUX_RGBImageRec(const char *FileName): data(NULL), NoErrors(false)
{
loadFile(FileName);
}

AUX_RGBImageRec::~AUX_RGBImageRec()
{
if (data != NULL) delete data;
data = NULL;
}

bool AUX_RGBImageRec::loadFile(const char* Filename)
{
BITMAPINFO BMInfo; // need the current OpenGL device contexts in order to make use of windows DIB utilities
const HDC gldc = wglGetCurrentDC(); // a handle for the current OpenGL Device Contexts
// assume there are errors until file is loaded successfully into memory
NoErrors = false; // release old data since this object could be used to load multiple Textures
if(data != NULL) delete data; // windows needs this info to determine what header info we are looking for
BMInfo.bmiHeader.biSize = sizeof(BITMAPINFOHEADER); // Get windows to determine color bit depth in the file for us
BMInfo.bmiHeader.biBitCount = 0; // Get windows to open and load the BMP file and handle the messy decompression if the file is compressed
// assume perfect world and no errors in reading file, Ha Ha
HANDLE DIBHandle = LoadImage(0,Filename, IMAGE_BITMAP, 0, 0,LR_DEFAULTCOLOR | LR_CREATEDIBSECTION | LR_LOADFROMFILE); // use windows to get header info of bitmap - assume no errors in header format

GetDIBits(gldc, (HBITMAP)DIBHandle, 0,0, NULL, &BMInfo, DIB_RGB_COLORS);
sizeX = BMInfo.bmiHeader.biWidth;
sizeY = BMInfo.bmiHeader.biHeight; // change color depth to 24 bits (3 bytes (BGR) / pixel)
BMInfo.bmiHeader.biBitCount = 24; // don't want the data compressed
BMInfo.bmiHeader.biCompression = BI_RGB;
const DWORD BitmapLength = sizeX * sizeY * 3; // 3 bytes (BGR) per pixel (24bp)
// allocate enough memory to hold the pixel data in client memory
data = new byte[BitmapLength]; // Get windows to do the dirty work of converting the BMP into the format needed by OpenGL
// if file is already 24 bit color then this is a waste of time but makes for short code
// Get the actual Texel data from the BMP object

if (GetDIBits(gldc, (HBITMAP)DIBHandle, 0, sizeY, data, &BMInfo, DIB_RGB_COLORS))
{
NoErrors = true;
convertBGRtoRGB(); // NOTE: BMP is in BGR format but OpenGL needs RGB unless you use GL_BGR_EXT
}

DeleteObject(DIBHandle); // don't need the BMP Object anymore
return NoErrors;
}


What i am struggling to understand now is how to use this. So i have the above and its h file saved in my project folder and linked to my project. Now in another class i am working in, i want to get a texture id, so i have this

#include "stdafx.h"
#include <windows.h>
#include <stdio.h> //for file access
#include <gl\gl.h>
#include <gl\glu.h>
#include "skybox.h"
#include "BMP.h"

bool skybox::Load_Texture(unsigned int & aTexture, char * fileName) {

if(!fileName) return false; //if no file name is given return

FILE *aFile = NULL;
AUX_RGBImageRec *image_record = NULL;

if((aFile = fopen(fileName, "rb")) == NULL) return false;

image_record = auxDIBImageLoadA(fileName); //Function to load BMP

if(!image_record) return false; //check that BMP loaded

glGenTextures(1, &aTexture); //generates 1 texture name

glPixelStorei (GL_UNPACK_ALIGNMENT, 1); //sets how the pixels of the texture are stored

glBindTexture(GL_TEXTURE_2D, aTexture); //binds the name to the target


//build prefiltered textures at different resolutions
gluBuild2DMipmaps(GL_TEXTURE_2D, 3, image_record->sizeX,
image_record->sizeY, GL_RGB, GL_UNSIGNED_BYTE, image_record->data);

//give the texture its attributes
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_NEAREST);
glTexEnvf(GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_MODULATE);

// Now we need to free the image data that we loaded since openGL stored it as a texture
if (image_record) { //if we stored data then free the memory
if (image_record->data) { //check if there is any data
free(image_record->data); //free the memory
}
free(image_record); //free the image record
}

return true; //everything should have worked so return true
}


So what changes would i need to make to the above to make it use the first class i posted? I think i have to change the first few lines of the above class but not sure what i am changing them too.

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