How to apply texture on a sphere

OpenGL OpenGL: Basic Coding
1

Basically the title says it all. Can I apply a texture on a sphere made with the gluSphere function? If yes, how?

I only did it on polygons as I’m super-new to OpenGL.

2

you may use command

void gluQuadsricTexture(GLUquadricObj *obj, GLenum textureCoords);

CODE
GLUquadricObj *quadricObj = gluNewQuadric();
gluQuadricDrawStyle(quadricObj, GLU_FILL);
gluSphere(quadricObj, 1, 20, 20);
gluQuadsricTexture(quadricObj, GL_TRUE);

3

Use gluQuadricTexture() to enable or disable the generation of texture coordinates for a quadric.

Everything else (enabling/disabling texturing, creating and binding textures, etc) is the same as for any other rendering operation.

4

Thanks guys. Sadly it still doesn’t work. Is there anything terribly wrong in this code?


void drawSpheres(GLuint _sphereTextureId){
				glColor3f(0.0,1.0,0.0);
				gluQuadricDrawStyle(pQuadric, GLU_FILL);
				glBindTexture(GL_TEXTURE_2D, _sphereTextureId);
				gluQuadricTexture(pQuadric, true);
				gluQuadricNormals(pQuadric, GLU_SMOOTH);
				glTranslatef(-200.0,200,-1000.0);
				gluSphere(pQuadric,radius,numSlices,numStacks);
	}
}

I know for sure that the .bmp file is correctly loaded, 'cause I tried to apply this texture on other objects. Still, nothing is happening on spheres.

5

Did you remember glEnable(GL_TEXTURE_2D)?

6

Yep, it’s right before the call to the function I posted above :\

7

The following works for me:


#include <GL/gl.h>
#include <GL/glu.h>
#include <GL/glut.h>

GLuint tex;
GLUquadric* sphere;

void make_tex(void)
{
    unsigned char data[256][256][3];
    for (int y = 0; y < 255; y++) {
	for (int x = 0; x < 255; x++) {
	    unsigned char *p = data[y][x];
	    p[0] = p[1] = p[2] = (x ^ y) & 8 ? 255 : 0;
	}
    }
    glGenTextures(1, &tex);
    glBindTexture(GL_TEXTURE_2D, tex);
    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, 256, 256, 0, GL_RGB, GL_UNSIGNED_BYTE, (const GLvoid *) data);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
}

void draw(void)
{
    glClearColor(0.5, 0.5, 1.0, 1);
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);

    glMatrixMode(GL_MODELVIEW);
    glLoadIdentity();
    glTranslatef(0.0, 0.0,-2.0);
    glRotatef(45, 0, 1, 0);

    glColor3f(0.0,1.0,0.0);
    gluQuadricDrawStyle(sphere, GLU_FILL);
    glBindTexture(GL_TEXTURE_2D, tex);
    gluQuadricTexture(sphere, GL_TRUE);
    gluQuadricNormals(sphere, GLU_SMOOTH);
    gluSphere(sphere, 1.0, 32, 16);

    glutSwapBuffers();
}

void resize(int w, int h)
{
    if (!h)
	h = 1;
    glViewport(0, 0, w, h);
    glMatrixMode(GL_PROJECTION);
    glLoadIdentity();
    gluPerspective(90.0, 1.0*w/h, 0.1, 100.0);
}

void init(void)
{
    glEnable(GL_DEPTH_TEST);
    make_tex();
    sphere = gluNewQuadric();
    glEnable(GL_TEXTURE_2D);
}

int main(int argc, char **argv)
{
    glutInit(&argc, argv);

    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE | GLUT_DEPTH);
    glutInitWindowSize(640, 512);

    glutCreateWindow("Test");

    glutDisplayFunc(draw);
    glutReshapeFunc(resize);

    init();

    glutMainLoop();
}