Original Post
How do i change it to load about 20 images without errors?
thanks
#include <windows.h>
#include <GL/gl.h>
#include <stdlib.h>
#include <GL/glut.h>
#include <gl/glaux.h>
#include <math.h>
DEVMODE DMsaved; // Saves The Previous Screen Settings (NEW)
GLfloat xrot; // X Rotation
GLfloat yrot; // Y Rotation
GLfloat zrot; // Z Rotation
GLuint texture[100]; // Storage For 1 Texture
typedef struct Texture_Image
{
int width; // Width Of Image In Pixels
int height; // Height Of Image In Pixels
int format; // Number Of Bytes Per Pixel
unsigned char *data; // Texture Data
} TEXTURE_IMAGE;
typedef TEXTURE_IMAGE *P_TEXTURE_IMAGE; // A Pointer To The Texture Image Data Type
P_TEXTURE_IMAGE t1; // Pointer To The Texture Image Data Type
P_TEXTURE_IMAGE t2; // Pointer To The Texture Image Data Type
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
// Allocate An Image Structure And Inside Allocate Its Memory Requirements
P_TEXTURE_IMAGE AllocateTextureBuffer( GLint w, GLint h, GLint f)
{
P_TEXTURE_IMAGE ti=NULL; // Pointer To Image Struct
unsigned char *c=NULL;
ti = (P_TEXTURE_IMAGE)malloc(sizeof(TEXTURE_IMAGE)); // One Image Struct Please
if( ti != NULL ) {
ti->width = w; // Set Width
ti->height = h; // Set Height
ti->format = f; // Set Format
c = (unsigned char *)malloc( w * h * f);
if ( c != NULL ) {
ti->data = c;
}
else {
MessageBox(NULL,"Could Not Allocate Memory For A Texture Buffer","BUFFER ERROR",MB_OK | MB_ICONINFORMATION);
return NULL;
}
}
else
{
MessageBox(NULL,"Could Not Allocate An Image Structure","IMAGE STRUCTURE ERROR",MB_OK | MB_ICONINFORMATION);
return NULL;
}
return ti; // Return Pointer To Image Struct
}
// Free Up The Image Data
void DeallocateTexture( P_TEXTURE_IMAGE t )
{
if(t)
{
if(t->data)
{
free(t->data); // Free Its Image Buffer
}
free(t); // Free Itself
}
}
// Read A .RAW File In To The Allocated Image Buffer Using data In The Image Structure Header.
// Flip The Image Top To Bottom. Returns 0 For Failure Of Read, Or Number Of Bytes Read.
int ReadTextureData ( char *filename, P_TEXTURE_IMAGE buffer)
{
FILE * f;
int i,j,k,done=0;
int stride = buffer->width * buffer->format; // Size Of A Row (Width * Bytes Per Pixel)
unsigned char *p = NULL;
f = fopen(filename, "rb"); // Open "filename" For Reading Bytes
if( f != NULL ) // If File Exists
{
for( i = buffer->height-1; i >= 0 ; i-- ) // Loop Through Height (Bottoms Up - Flip Image)
{
p = buffer->data + (i * stride );
for ( j = 0; j < buffer->width ; j++ ) // Loop Through Width
{
for ( k = 0 ; k < buffer->format-1 ; k++, p++, done++ )
{
*p = fgetc(f); // Read Value From File And Store In Memory
}
*p = 255; p++; // Store 255 In Alpha Channel And Increase Pointer
}
}
fclose(f); // Close The File
}
else // Otherwise
{
MessageBox(NULL,"Unable To Open Image File","IMAGE ERROR",MB_OK | MB_ICONINFORMATION);
}
return done; // Returns Number Of Bytes Read In
}
void BuildTexture (P_TEXTURE_IMAGE tex)
{
glGenTextures(1, &texture[0]);
glBindTexture(GL_TEXTURE_2D, texture[0]);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MAG_FILTER,GL_LINEAR);
glTexParameteri(GL_TEXTURE_2D,GL_TEXTURE_MIN_FILTER,GL_LINEAR);
gluBuild2DMipmaps(GL_TEXTURE_2D, GL_RGB, tex->width, tex->height, GL_RGBA, GL_UNSIGNED_BYTE, tex->data);
}
void Blit( P_TEXTURE_IMAGE src, P_TEXTURE_IMAGE dst, int src_xstart, int src_ystart, int src_width, int src_height,
int dst_xstart, int dst_ystart, int blend, int alpha)
{
int i,j,k;
unsigned char *s, *d; // Source & Destination
// Clamp Alpha If Value Is Out Of Range
if( alpha > 255 ) alpha = 255;
if( alpha < 0 ) alpha = 0;
// Check For Incorrect Blend Flag Values
if( blend < 0 ) blend = 0;
if( blend > 1 ) blend = 1;
d = dst->data + (dst_ystart * dst->width * dst->format); // Start Row - dst (Row * Width In Pixels * Bytes Per Pixel)
s = src->data + (src_ystart * src->width * src->format); // Start Row - src (Row * Width In Pixels * Bytes Per Pixel)
for (i = 0 ; i < src_height ; i++ ) // Height Loop
{
s = s + (src_xstart * src->format); // Move Through Src Data By Bytes Per Pixel
d = d + (dst_xstart * dst->format); // Move Through Dst Data By Bytes Per Pixel
for (j = 0 ; j < src_width ; j++ ) // Width Loop
{
for( k = 0 ; k < src->format ; k++, d++, s++) // "n" Bytes At A Time
{
if (blend) // If Blending Is On
*d = ( (*s * alpha) + (*d * (255-alpha)) ) >> 8; // Multiply Src Data*alpha Add Dst Data*(255-alpha)
else // Keep in 0-255 Range With >> 8
*d = *s; // No Blending Just Do A Straight Copy
}
}
d = d + (dst->width - (src_width + dst_xstart))*dst->format; // Add End Of Row
s = s + (src->width - (src_width + src_xstart))*src->format; // Add End Of Row
}
}
int InitGL(GLvoid) // This Will Be Called Right After The GL Window Is Created
{
t1 = AllocateTextureBuffer( 256, 256, 4 ); // Get An Image Structure
if (ReadTextureData("Data/Monitor.raw",t1)==0) // Fill The Image Structure With Data
{ // Nothing Read?
MessageBox(NULL,"Could Not Read ''Monitor.raw'' Image Data","TEXTURE ERROR",MB_OK | MB_ICONINFORMATION);
return FALSE;
}
t2 = AllocateTextureBuffer( 256, 256, 4 ); // Second Image Structure
if (ReadTextureData("Data/GL.raw",t2)==0) // Fill The Image Structure With Data
{ // Nothing Read?
MessageBox(NULL,"Could Not Read ''GL.raw'' Image Data","TEXTURE ERROR",MB_OK | MB_ICONINFORMATION);
return FALSE;
}
// Image To Blend In, Original Image, Src Start X & Y, Src Width & Height, Dst Location X & Y, Blend Flag, Alpha Value
Blit(t2,t1,127,127,128,128,64,64,1,127);
BuildTexture (t1); // Load The Texture Map Into Texture Memory
DeallocateTexture( t1 ); // Clean Up Image Memory Because Texture Is
DeallocateTexture( t2 ); // In GL Texture Memory Now
glEnable(GL_TEXTURE_2D); // Enable Texture Mapping
glShadeModel(GL_SMOOTH); // Enables Smooth Color Shading
glClearColor(0.0f, 0.0f, 0.0f, 0.0f); // This Will Clear The Background Color To Black
glClearDepth(1.0); // Enables Clearing Of The Depth Buffer
glEnable(GL_DEPTH_TEST); // Enables Depth Testing
glDepthFunc(GL_LESS); // The Type Of Depth Test To Do
return TRUE;
}
GLvoid DrawGLScene(GLvoid)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); // Clear The Screen And The Depth Buffer
glLoadIdentity(); // Reset The View
glTranslatef(0.0f,0.0f,-5.0f);
glRotatef(xrot,1.0f,0.0f,0.0f);
glRotatef(yrot,0.0f,1.0f,0.0f);
glRotatef(zrot,0.0f,0.0f,1.0f);
glBindTexture(GL_TEXTURE_2D, texture[0]);
glBegin(GL_QUADS);
// Front Face
glNormal3f( 0.0f, 0.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f);
// Back Face
glNormal3f( 0.0f, 0.0f,-1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
// Top Face
glNormal3f( 0.0f, 1.0f, 0.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, 1.0f, 1.0f);
// Bottom Face
glNormal3f( 0.0f,-1.0f, 0.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
// Right Face
glNormal3f( 1.0f, 0.0f, 0.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f( 1.0f, -1.0f, -1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f( 1.0f, 1.0f, -1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f( 1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f( 1.0f, -1.0f, 1.0f);
// Left Face
glNormal3f(-1.0f, 0.0f, 0.0f);
glTexCoord2f(0.0f, 0.0f); glVertex3f(-1.0f, -1.0f, -1.0f);
glTexCoord2f(1.0f, 0.0f); glVertex3f(-1.0f, -1.0f, 1.0f);
glTexCoord2f(1.0f, 1.0f); glVertex3f(-1.0f, 1.0f, 1.0f);
glTexCoord2f(0.0f, 1.0f); glVertex3f(-1.0f, 1.0f, -1.0f);
glEnd();
xrot+=0.3f;
yrot+=0.2f;
zrot+=0.4f;
}
GLvoid KillGLWindow(GLvoid) // Properly Kill The Window
{
if (fullscreen) // Are We In Fullscreen Mode?
{
if (!ChangeDisplaySettings(NULL,CDS_TEST)) { // If The Shortcut Doesn''t Work
ChangeDisplaySettings(NULL,CDS_RESET); // Do It Anyway (To Get The Values Out Of The Registry)
ChangeDisplaySettings(&DMsaved,CDS_RESET); // Change Resolution To The Saved Settings
}
else // Not Fullscreen
{
ChangeDisplaySettings(NULL,CDS_RESET); // Do Nothing
}
ShowCursor(TRUE); // Show Mouse Pointer
}
if (hRC) // Do We Have A Rendering Context?
{
if (!wglMakeCurrent(NULL,NULL)) // Are We Able To Release The DC And RC Contexts?
{
MessageBox(NULL,"Release Of DC And RC Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
}
if (!wglDeleteContext(hRC)) // Are We Able To Delete The RC?
{
MessageBox(NULL,"Release Rendering Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
}
hRC=NULL; // Set RC To NULL
}
if (hDC && !ReleaseDC(hWnd,hDC)) // Are We Able To Release The DC
{
MessageBox(NULL,"Release Device Context Failed.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hDC=NULL; // Set DC To NULL
}
if (hWnd && !DestroyWindow(hWnd)) // Are We Able To Destroy The Window?
{
MessageBox(NULL,"Could Not Release hWnd.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hWnd=NULL; // Set hWnd To NULL
}
if (!UnregisterClass("OpenGL",hInstance)) // Are We Able To Unregister Class
{
MessageBox(NULL,"Could Not Unregister Class.","SHUTDOWN ERROR",MB_OK | MB_ICONINFORMATION);
hInstance=NULL; // Set hInstance To NULL
}
}