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fishbulb52

OpenGL MD2 and OpenGL Game Programming code...

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fishbulb52    122
Hello everyone! I've been battling with MD2's for the last two days, and I've run into a little problem... I've basically copied the code from OpenGL Game Programming, and changed it a tad so that I wouldn't have to worry about textures just yet. The program compiles with no errors or warnings, but when I run it, it doesn't display the model at all, and it sucks up all my ram in a matter of seconds! I'm using Dev-C++ to do this, by the way. Here's my code:
 
// Includes

#include <stdlib.h>
#include <windows.h>
#include <gl/gl.h>
#include <stdio.h>
#include <stdlib.h>

// Function Declarations

// START MD2 JUNK

//header declarations... took a while to figure out this was missing...
typedef struct
{
        int ident;
        int version;
        int skinwidth;
        int skinheight;
        int framesize;
        int numSkins;
        int numXYZ;
        int numST;
        int numTris;
        int numGLcmds;
        int numFrames;
        int offsetSkins;
        int offsetST;
        int offsetTris;
        int offsetFrames;
        int offsetGLcmds;
        int offsetEnd;
} modelHeader_t;

//Vectors, in all their glory!

typedef struct
{
 float point[3];
} vector_t;


//Vector Subtraction...

vector_t operator-(vector_t a, vector_t b)
{
 vector_t c;

 c.point[0] = a.point[0] - b.point[0];
 c.point[1] = a.point[1] - b.point[1];
 c.point[2] = a.point[2] - b.point[2];

 return c;
}

//Vector Multiplication...

vector_t operator*(float f, vector_t b)
{
 vector_t c;

 c.point[0] = f * b.point[0];
 c.point[1] = f * b.point[1];
 c.point[2] = f * b.point[2];

 return c;
}

//Vector Division...

vector_t operator/(vector_t a, vector_t b)
{
 vector_t c;

 c.point[0] = a.point[0]/b.point[0];
 c.point[1] = a.point[1]/b.point[1];
 c.point[2] = a.point[2]/b.point[2];

 return c;
}

//Vector Addition...

vector_t operator+(vector_t a, vector_t b)
{
 vector_t c;

 c.point[0] = a.point[0] + b.point[0];
 c.point[1] = a.point[1] + b.point[1];
 c.point[2] = a.point[2] + b.point[2];

 return c;
}

//All About Textures!

//A texture coordinate!!

typedef struct
{
 float s;
 float t;
} texCoord_t;

//Index of a texture coordinate!!

typedef struct
{
 short s;
 short t;
} stIndex_t;


//These are the supported formats:
enum texTypes_t
{
 PCX, BMP, TGA
};

//A simple texture...

typedef struct
{
 texTypes_t textureType;          //type of image file this texture is...

 int width;
 int height;
 long int scaledWidth;
 long int scaledHeight;
 unsigned int texID;              //texture object ID.
 unsigned char *data;             //texture data.
 unsigned char *palette;          //palette for texture (if it exists).
} texture_t;





//A single frame point!!

typedef struct
{
 unsigned char v[3];                 //point info
 unsigned char normalIndex;          //not used... just so it loads...
} framePoint_t;

//Info for that single frame...

typedef struct
{
 float scale [3];                    //scaling of the vertices.
 float translate[3];                 //translation for the vertices.
 char name[16];                      //name of the model.
 framePoint_t fp[1];                 //starting point in memory of
} frame_t;                           //frames's vertex list.

//A triangle, since the MD2 format is all triangles.

typedef struct
{
 unsigned short meshIndex[3];        //vertex indices.
 unsigned short stIndex[3];          //texture-coordinate indices.
} mesh_t;


//The model data for a single model - where it all ties together!

typedef struct
{
 int numFrames;
 int numPoints;
 int numTriangles;
 int numST;
 int frameSize;                      //size of each frame in bytes.
 int texWidth, texHeight;
 int currentFrame;                   //current frame # in animation.
 int nextFrame;                      //next frame #.
 float interpol;                     //percentage through frame.
 mesh_t *triIndex;                   //triangle list.
 texCoord_t *st;                    //texture coordinate list
 vector_t *pointList;                //vertex list
 texture_t *modelTex;                //texture data
} modelData_t;



//LOAD THE MODEL!!
modelData_t *LoadMD2Model(char *filename, char *textureName)
{
 FILE *filePtr;                      //file pointer
 int fileLen;                        //length of model file
 char *buffer;                       //file buffer

 modelData_t *model;                 //the model
 modelHeader_t *modelHeader;         //model header
 texture_t *md2Texture;              //model texture

 stIndex_t *stPtr;                   //texture indices
 frame_t *frame;                     //frame data
 vector_t *pointListPtr;             //index variable
 mesh_t *triIndex, *bufIndexPtr;     //index variables
 int i, j;                           //index variables


 //open the model file
 filePtr = fopen(filename, "rb");
 if (filePtr == NULL)
    return NULL;

 //find length of file
 fseek(filePtr, 0, SEEK_END);
 fileLen = ftell(filePtr);
 fseek(filePtr, 0, SEEK_SET);

 //read entire file into buffer
 buffer = (char*)malloc(fileLen + 1);
 fread(buffer, sizeof(char), fileLen, filePtr);

 //extract model file header from buffer
 modelHeader = (modelHeader_t*)buffer;

 //allocate memory for model data
 model = (modelData_t*)malloc(sizeof(modelData_t));
 if (model == NULL)
    return NULL;

 //allocate memory for all vertices on all frames
 model->pointList = (vector_t*)malloc(sizeof(vector_t)*modelHeader->numXYZ *
                     modelHeader->numFrames);

 //store vital model data
 model->numPoints = modelHeader->numXYZ;            //number of vertices
 model->numFrames = modelHeader->numFrames;         //number of frames
 model->frameSize = modelHeader->framesize;         //size of each frame

 //loop number of frames in model
 for(j = 0; j < modelHeader->numFrames; j++)
 {
       //offset points in this frame.
       frame = (frame_t*)&buffer[modelHeader->offsetFrames +
             modelHeader->framesize * j];

       //calculate the point positions based on frame details
       pointListPtr = (vector_t*)&model->pointList[modelHeader->numXYZ * j];
       for(i = 0; i < modelHeader->numXYZ; i++)
       {
             pointListPtr[i].point[0] = frame->scale[0] * frame->fp[i].v[0] +
                                        frame->translate[0];
             pointListPtr[i].point[1] = frame->scale[1] * frame->fp[i].v[1] +
                                        frame->translate[1];
             pointListPtr[i].point[2] = frame->scale[2] * frame->fp[i].v[2] +
                                        frame->translate[2];
        }
 }


/*
 //load the model texture
 md2Texture = LoadTexture(textureName);
 if (md2Texture != NULL)
 {
    //set texture up for OpenGL and store it (in the model data structure)
    SetupMd2Texture(md2Texture);
    model->modelTex = md2Texture;
 }
 else
     return NULL;

 //alocate memory for the model texture coordinates
 model->st = (texCoord_t*)malloc(sizeof(texCoord_t)*modelHeader->numST);

 //store number of texture coordinates
 model->numST = modelHeader->numST;

 //set texture pointer to texture coordinate offset
 strPtr = (stIndex_t*)&buffer[modelHeader->offsetST];

 //calculate and store the texture coordinates for the model
 for (i = 0; i < modelHeader->numST; i++)
 {
     model->st[i].s = (float)stPtr[i].s / (float)md2Texture->width;
     model->st[i].t = (float)stPtr[i].t / (float)md2Texture->height;
 }
*/
//A bunch of stuff wrong with these... who knows... figure it out later...
//not using textures now anyway... and no, im not rationalizing >_> 


 //allocate the list of triangle indices
 triIndex = (mesh_t*)malloc(sizeof(mesh_t) * modelHeader->numTris);

 //set total number of triangles
 model->numTriangles = modelHeader->numTris;
 model->triIndex = triIndex;

 //point to triangle indices in buffer
 bufIndexPtr = (mesh_t*)&buffer[modelHeader->offsetTris];



 //create a mesh (triangle) list by looping!!
 for (j = 0; j < model->numFrames; j++)
 {
     //for all triangles in each frame
     for(i = 0; i < modelHeader->numTris; i++)
     {
           //store the mesh and texture indices...
           triIndex[i].meshIndex[0] = bufIndexPtr[i].meshIndex[0];
           triIndex[i].meshIndex[1] = bufIndexPtr[i].meshIndex[1];
           triIndex[i].meshIndex[2] = bufIndexPtr[i].meshIndex[2];
           triIndex[i].stIndex[0] = bufIndexPtr[i].meshIndex[0];
           triIndex[i].stIndex[1] = bufIndexPtr[i].meshIndex[1];
           triIndex[i].stIndex[2] = bufIndexPtr[i].meshIndex[2];
     }
 }

 //close file and free memory
 fclose(filePtr);
 free(buffer);

 //initialize the animation variables
 model->currentFrame = 0;
 model->nextFrame = 1;
 model->interpol = 0.0;

 return model;
}

 //The Function to DISPLAY THE MODEL!! IMPORTANT!!!
void DisplayMD2(modelData_t *model, int frameNum)
{
     vector_t *pointList;            //current frame's vertices
     int i;                         //index counter

     //create the pointer to the frame we want to show
     pointList = &model->pointList[model->numPoints * frameNum];

     //display the model as SOLID TRIANGLES!!
     glBegin(GL_TRIANGLES);
             for(i = 0; i < model->numTriangles; i++)
             {
                 glVertex3fv(pointList[model->triIndex[i].meshIndex[0]].point);
                 glVertex3fv(pointList[model->triIndex[i].meshIndex[2]].point);
                 glVertex3fv(pointList[model->triIndex[i].meshIndex[1]].point);
             }
     glEnd;
}


// End MD2 junk



LRESULT CALLBACK 
WndProc( HWND hWnd, UINT message,
WPARAM wParam, LPARAM lParam );
VOID EnableOpenGL( HWND hWnd, HDC * hDC, HGLRC * hRC );
VOID DisableOpenGL( HWND hWnd, HDC hDC, HGLRC hRC );

// WinMain

int WINAPI 
WinMain( HINSTANCE hInstance,
HINSTANCE hPrevInstance,
LPSTR lpCmdLine,
int iCmdShow )
{
WNDCLASS wc;
HWND hWnd;
HDC hDC;
HGLRC hRC;
MSG msg;
BOOL bQuit = FALSE;
float theta = 0.0f;

// register window class
wc.style = CS_OWNDC;
wc.lpfnWndProc = WndProc;
wc.cbClsExtra = 0;
wc.cbWndExtra = 0;
wc.hInstance = hInstance;
wc.hIcon = LoadIcon( NULL, IDI_APPLICATION );
wc.hCursor = LoadCursor( NULL, IDC_ARROW );
wc.hbrBackground = (HBRUSH)GetStockObject( BLACK_BRUSH );
wc.lpszMenuName = NULL;
wc.lpszClassName = "MainWindow";
RegisterClass( &wc );

// create main window
hWnd = CreateWindow( 
"MainWindow", "MD2 Thing",
WS_CAPTION | WS_POPUPWINDOW | WS_VISIBLE,
50, 50, 600, 600,
NULL, NULL, hInstance, NULL );

// enable OpenGL for the window
EnableOpenGL( hWnd, &hDC, &hRC );

// program main loop
while ( !bQuit ) {

// check for messages
if ( PeekMessage( &msg, NULL, 0, 0, PM_REMOVE ) ) {

// handle or dispatch messages
if ( msg.message == WM_QUIT ) {
bQuit = TRUE;
} else {
TranslateMessage( &msg );
DispatchMessage( &msg );
}

} else {

// OpenGL animation code goes here
glTranslatef(0.0f, 0.0f, -10.0f);
modelData_t *Hobgoblin;
Hobgoblin = LoadMD2Model("hobgoblin.md2", "hobgoblin.pcx");
DisplayMD2(Hobgoblin, 0);


}

}

// shutdown OpenGL
DisableOpenGL( hWnd, hDC, hRC );

// destroy the window explicitly
DestroyWindow( hWnd );

return msg.wParam;

}

// Window Procedure

LRESULT CALLBACK 
WndProc( HWND hWnd, UINT message,
WPARAM wParam, LPARAM lParam )
{

switch ( message ) {

case WM_CREATE:
return 0;

case WM_CLOSE:
PostQuitMessage( 0 );
return 0;

case WM_DESTROY:
return 0;

case WM_KEYDOWN:
switch ( wParam ) {

case VK_ESCAPE:
PostQuitMessage( 0 );
return 0;

}
return 0;

default:
return DefWindowProc( hWnd, 
message, wParam, lParam );

}

}

// Enable OpenGL

VOID EnableOpenGL( HWND hWnd, HDC * hDC, HGLRC * hRC )
{
PIXELFORMATDESCRIPTOR pfd;
int iFormat;

// get the device context (DC)
*hDC = GetDC( hWnd );

// set the pixel format for the DC
ZeroMemory( &pfd, sizeof( pfd ) );
pfd.nSize = sizeof( pfd );
pfd.nVersion = 1;
pfd.dwFlags = PFD_DRAW_TO_WINDOW | 
PFD_SUPPORT_OPENGL | PFD_DOUBLEBUFFER;
pfd.iPixelType = PFD_TYPE_RGBA;
pfd.cColorBits = 24;
pfd.cDepthBits = 16;
pfd.iLayerType = PFD_MAIN_PLANE;
iFormat = ChoosePixelFormat( *hDC, &pfd );
SetPixelFormat( *hDC, iFormat, &pfd );

// create and enable the render context (RC)
*hRC = wglCreateContext( *hDC );
wglMakeCurrent( *hDC, *hRC );

}

// Disable OpenGL

VOID DisableOpenGL( HWND hWnd, HDC hDC, HGLRC hRC )
{
wglMakeCurrent( NULL, NULL );
wglDeleteContext( hRC );
ReleaseDC( hWnd, hDC );
} 


I've searched the forums, and found a post about how this code only works with unoptimized MD2 models... well this doesn't work with the old ones either; I checked.

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