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nickme

OpenGL vs 2010 C++:can i use texture1D and texture2D at the same program?

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nickme    253
hi

i'd recently written a program about fractals. i would like to show a png file to the screen at the beginning of the program to illustrate the various key broad commands for using the program. in my fractal program, i used a raw file texture1D for palette for the fractals. because the splashscreen is 2d, when i ran the program, the color of my fractals is different. i wonder if that is the problem with my program or that opengl does not allow one to use both texture 1D and 2D at the same time.

thanks

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Ashaman73    13715
[quote name='nickme' timestamp='1353644402' post='5003372']
is the problem with my program
[/quote]
Yes. There should be no issues using 1D,2D,3D,cube whatever textures concurrently :D

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nickme    253
[source lang="cpp"]#include <math.h>
#include <stdio.h>
#include <gl/glut.h>
GLuint SplashScreen;

const GLint win_sizeX = 1024, win_sizeY = 1024;
const GLint w = 1024.0, h = 1024;
const GLdouble wleft = -win_sizeX *0.5, wright = win_sizeX *0.5, wtop = win_sizeY * 0.5, wbottom = - win_sizeY * 0.5;

void clear()
{
glClearColor(1.0, 1.0, 0.0, 1.0);
glClear(GL_COLOR_BUFFER_BIT);
}

GLuint LoadTexture2D( const char * filename, int width, int height)
{
GLuint texture;
FILE * file;

file = fopen( filename, "rb" );
if ( file == NULL ) {
system("PAUSE");
exit(1);
}

GLubyte * data = new unsigned char [width * height * 4];

fread( data, 1, width * height * 4, file );
fclose( file );
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glGenTextures( 1, &texture );

glBindTexture( GL_TEXTURE_2D, texture );

glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_DECAL);

glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
glTexParameteri( GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, data);

delete [] data;
return texture;
}

void display_splash_screen(int time)
{
clear();
glEnable( GL_TEXTURE_2D );
glTexEnvf( GL_TEXTURE_ENV, GL_TEXTURE_ENV_MODE, GL_REPLACE);
glBindTexture( GL_TEXTURE_2D, SplashScreen);

glBegin( GL_QUADS );

glTexCoord2d(0.0,0.0); glVertex2d(wleft, wtop);
glTexCoord2d(1.0,0.0); glVertex2d(wright, wtop);
glTexCoord2d(1.0,1.0); glVertex2d(wright, wbottom);
glTexCoord2d(0.0,1.0); glVertex2d(wleft, wbottom);

glEnd();
glFlush();
Sleep(time);
}

void init()
{
glDisable(GL_CULL_FACE);
glDisable(GL_DEPTH_TEST);
glShadeModel(GL_FLAT);

glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
SplashScreen = LoadTexture2D("SplashScreen.raw", w, h);
}

void render() {
clear();
display_splash_screen(0);
}

void winReshapeFcn(GLint newWidth, GLint newHeight)
{
glutReshapeWindow(w, h);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
gluOrtho2D(wleft, wright, wbottom, wtop);
glMatrixMode(GL_MODELVIEW);
}

void processNormalKeys(unsigned char key, int x, int y)
{
if (key == 27)
exit(0);
}

int main(int argc, char** argv) {
glutInit(&argc, argv);
glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB);
glutInitWindowPosition(0, 0);
glutInitWindowSize(win_sizeX, win_sizeY);
glutCreateWindow(" Texture testing ");

init();
glutIgnoreKeyRepeat(0);
glutReshapeFunc(winReshapeFcn);
glutDisplayFunc(render);
glutKeyboardFunc(processNormalKeys);

glutMainLoop();
glDeleteTextures(1, &SplashScreen);

return 0;
}
[/source]
hi

i copy and paste the program to a smaller program to test the 2d texture loading function. i include the source code for the program below. following that is the splashscreen that it suppose to render and finally the actual output from the program.

thank in advance.

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nickme    253
apparrently, i can only attach one image at one time. here is the splash screen of the actual file. it seem i can not upload the raw file so i loaded the equivalent png file instead.

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nickme    253
hi mhagain:

i checked the dimension of the raw file with photo shop, it is 1024X1024. but i am not sure what the bpp is. how to find that out or change it? i originally created the splashscreen in png format, because i don't know how to load png file, i convert it to raw file with "total image converter" i found on the web.

thanks

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nickme    253
hi

finally, i got the above program to works. however, when i added the LoadTexre2D to my fractals program, it messed up the color of my fractals when rendered after the display splash screen. i tried to put glLoadIdentity() and glPushMatrix and glPopMatrix between display as it to insulate the color buffer but the problem still persists. i know, that is not very smart.

what should i look at? is it because i used texture1D and texture2D?

any advice will be appreciated. Edited by nickme

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nickme    253
the following attached file show a image when i ran the fractal program without the splashscreen 2D texture. the next attachment show the fractal rendered with splashscreen 2D texture, it looks like a negative film.

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nickme    253
hi,

i finally figured out what was wrong with my program. i did not but the glDisable(GL_TEXTURE_2D); after i finished using it. so when i used texture2D, i had the problem that it did.

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