What's wrong with glut function?

OpenGL OpenGL: Basic Coding
1

This is a program using multi-samples to perform anti-aliasing, but when i run this I got a error message in command line, like the following:

GLUT: Fatal Error in e:\programing\OpenGL\programs\6-6-163\debug\6-6-163.exe: pi
xel format with necessary capabilities not found.
Press any key to continue . . .

Have you ever seen this before, what’s wrong?

Here is my code:

#include <stdio.h>
#include <windows.h>
#include <GL/glew.h>
#include <GL/glut.h>

static int bgtoggle = 1 ;

void init(void)
{
	GLint buf, sbuf ;
	int i, j ;
	glClearColor(0.0, 0.0, 0.0, 0.0) ;
	glGetIntegerv(GL_SAMPLE_BUFFERS, &buf) ;
	printf("number of sample buffers is %d
", buf) ;
	glGetIntegerv(GL_SAMPLES, &sbuf) ;
	printf("number of samples is %d
", sbuf) ;

	glNewList(1, GL_COMPILE) ;
	for(i=0; i<19; i++)
	{
		glPushMatrix() ;
		glRotatef(360.0*(float)i/19.0, 0.0, 0.0, 1.0) ;
		glColor3f(1.0, 1.0, 1.0) ;
		glLineWidth((i%3)+1.0) ;
		glBegin(GL_LINES) ;
			glVertex2f(0.25, 0.05) ;
			glVertex2f(0.9, 0.2) ;
		glEnd() ;
		glColor3f(0.0, 1.0, 1.0) ;
		glBegin(GL_TRIANGLES) ;
			glVertex2f(0.25, 0.0) ;
			glVertex2f(0.9, 0.0) ;
			glVertex2f(0.875, 0.10) ;
		glEnd() ;
		glPopMatrix() ;
		glEndList() ;

		glNewList(2, GL_COMPILE) ;
		glColor3f(1.0, 0.5, 0.0) ;
		glBegin(GL_QUADS) ;
		for(i=0; i<16; i++)
		{
			for(j=0; j<16; j++)
			{
				if((i+j)%2==0)
				{
					glVertex2f(-2.0 + (i*0.25), -2.0 +(j*0.25)) ;
					glVertex2f(-2.0 + (i*0.25), -1.75 + (j*0.25)) ;
					glVertex2f(-1.75 + (i*0.25), -1.75 +(j*0.25)) ;
					glVertex2f(-1.75 + (i*0.25), -2.0 +(j*0.25)) ;
				}
			}
		}
		glEnd() ;
		glEndList() ;
	}
}
void display(void)
{
	glClear(GL_COLOR_BUFFER_BIT) ;
	
	if(bgtoggle)
		glCallList(2) ;

	glEnable(GL_MULTISAMPLE) ;
	glPushMatrix() ;
	glTranslatef(-1.0, 0.0, 0.0) ;
	glCallList(1) ;
	glPopMatrix() ;

	glDisable(GL_MULTISAMPLE) ;
	glPushMatrix() ;
	glTranslatef(1.0, 0.0, 0.0) ;
	glCallList(1) ;
	glPopMatrix() ;
	glutSwapBuffers() ;

}

void reshape(int w, int h)
{
	glViewport(0, 0, (GLsizei)w, (GLsizei)h) ;
	glMatrixMode(GL_PROJECTION) ;
	glLoadIdentity() ;
	if(w<=h)
		gluOrtho2D(-1.0, 1.0, -1.0*(GLfloat)h/(GLfloat)w,
		1.0*(GLfloat)h/(GLfloat)w) ;
	else
		gluOrtho2D(-1.0*(GLfloat)w/(GLfloat)h, 
		1.0*(GLfloat)w/(GLfloat)h, -1.0, 1.0) ;
	glMatrixMode(GL_MODELVIEW) ;
	glLoadIdentity() ;
}

void keyboard(unsigned char key, int x, int y) 
{
		switch(key)
	{
	case 'b':
	case 'B':
		bgtoggle = !bgtoggle ;
		glutPostRedisplay() ;
		break ;

	case 27:
		exit(0) ;
		break ;

	default: 
		break ;
	}
}

int main(int argc, char **argv) 
{
	glutInit(&argc, argv) ;
	glutInitDisplayMode(GLUT_SINGLE|GLUT_INDEX) ;
	glutInitWindowSize(200, 200) ;
	glutCreateWindow("I love OpenGL") ;
	init() ;
	glutReshapeFunc(reshape) ;
	glutKeyboardFunc(keyboard) ;
	glutDisplayFunc(display) ;
	glutMainLoop() ;

	return 0 ;
}
2

glutInitDisplayMode(GLUT_SINGLE|GLUT_INDEX);

your graphics board doesn’t suppert indexed color mode…

3

OK, I think i need to buy a better video card.

4

what about glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);

or is there a reason that you need index colors?

5

Really? You won’t find one that supports index color mode, it was dropped some 15 years ago :slight_smile: Do you really need it? You use rgba colors in you code… Am I missing something?

6

slow, zengar…too slow :smiley:

7

OK, if using glutInitDisplayMode(GLUT_SINGLE | GLUT_RGBA);
I got the following message in command line:

number of sample buffers is 0
number of samples is 0

why?

8

OH, sorry, I lost a “}” before gfEndlist()

for(i=0; i<16; i++)
	{
		for(j=0; j<16; j++)
		{
			if((i+j)%2==0)
			{
				glVertex2f(-2.0 + (i*0.25), -2.0 +(j*0.25)) ;
				glVertex2f(-2.0 + (i*0.25), -1.75 + (j*0.25)) ;
				glVertex2f(-1.75 + (i*0.25), -1.75 +(j*0.25)) ;
				glVertex2f(-1.75 + (i*0.25), -2.0 +(j*0.25)) ;
			}
		}
	}
	glEnd() ;
	glEndList() ;

It’s OK now, Thank you all!