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Aycha
04-15-2010, 11:13 AM
how can i write any text in opengl ??

Mukund
04-15-2010, 11:26 AM
U can use glutBitmapCharacter()

http://www.opengl.org/resources/libraries/glut/spec3/node76.html
I hope this helps.

Aycha
04-15-2010, 11:36 AM
where i will add position of text ?
it will display only 1 alphabet when i call glutBitmapCharacter();?

Aycha
04-15-2010, 11:38 AM
#include <windows.h> // standard Windows app include

#include <gl/gl.h> // standard OpenGL include
#include <gl/glu.h> // OpenGL utilties
#include <GL/glut.h>


#define RED 1
#define GREEN 2
#define BLUE 3
#define WHITE 4
float red=1.0, blue=1.0, green=1.0;
int shoulder = 0, elbow = 0;

void init(void)
{
glClearColor (0.0, 0.0, 1.0, 0.0);
glShadeModel (GL_FLAT);
}

void display(void)
{
glClear (GL_COLOR_BUFFER_BIT);
glColor3f(red,green,blue);
glPushMatrix();
glTranslatef (-1.0, 0.0, 0.0);
glRotatef ((GLfloat) shoulder, 0.0, 0.0, 1.0);
glTranslatef (1.0, 0.0, 0.0);
glPushMatrix();
glScalef (2.0, 0.4, 1.0);
glColor3f(red,green,blue);
glutWireCube (1.2);
glPopMatrix();

glTranslatef (1.0, 0.0, 0.0);
glRotatef ((GLfloat) elbow, 0.0, 0.0, 1.0);
glTranslatef (1.0, 0.0, 0.0);
glPushMatrix();
glScalef (2.0, 0.4, 1.0);
glutSolidCube (1.0);
glPopMatrix();

glPopMatrix();
glutSwapBuffers();

}

void processMenuEvents(int option) {

switch (option) {
case RED : red = 1.0; green = 0.0; blue = 0.0; break;
case GREEN : red = 0.0; green = 1.0; blue = 0.0; break;
case BLUE : red = 0.0; green = 0.0; blue = 1.0; break;
case WHITE : red = 1.0; green = 1.0; blue = 1.0; break;
}
}



void reshape (int w, int h)
{
glViewport (0, 0, (GLsizei) w, (GLsizei) h);
glMatrixMode (GL_PROJECTION);
glLoadIdentity ();
gluPerspective(65.0, (GLfloat) w/(GLfloat) h, 1.0, 20.0);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef (0.0, 0.0, -5.0);
}

void keyboard (unsigned char key, int x, int y)
{
switch (key) {
case 's':
shoulder = (shoulder + 5) % 360;
glutPostRedisplay();
break;
case 'S':
shoulder = (shoulder - 5) % 360;
glutPostRedisplay();
break;
case 'e':
elbow = (elbow + 5) % 360;
glutPostRedisplay();
break;
case 'E':
elbow = (elbow - 5) % 360;
glutPostRedisplay();
break;
case 27:
exit(0);
break;
default:
break;
}
}

int main(int argc, char** argv)
{
glutInit(&amp;argc, argv);
glutInitDisplayMode (GLUT_DOUBLE | GLUT_RGB);
glutInitWindowSize (500, 500);
glutInitWindowPosition (100, 100);
glutCreateWindow (argv[0]);
init ();
glutDisplayFunc(display);
glutReshapeFunc(reshape);
glutKeyboardFunc(keyboard);

glutCreateMenu(processMenuEvents);
glutAddMenuEntry("Red",RED);
glutAddMenuEntry("Blue",BLUE);
glutAddMenuEntry("Green",GREEN);
glutAddMenuEntry("White",WHITE);
glutAttachMenu(GLUT_RIGHT_BUTTON);

glutMainLoop();
return 0;
}
can u add some text at the (0,0) location?

Mukund
04-15-2010, 07:33 PM
You can set the raster position to whichever location in the window that you choose.
Then you can use glutBitmapCharacter()

glRasterPos2f(0.0 , 0.0);
/*Then add text */