CODEWITHSUNDEEP
openglrandomsrand
Nevres Jahic
Nevres Jahic

Reputation: 1

opengl random number generation

I am creating simple 10x10 maze using gl_line_strip. i have two kinds of shapes regarding of random number generated. Problem is that it allways generates same random number(in my case zero)

void display(void){
glClear( GL_COLOR_BUFFER_BIT); 
glColor3f(1.0, 0.0, 0.0);
GLdouble myArray[2] ={0,0.1};
GLint a;
srand(time(0));
for (int i = 0; i < 10; i++)
{
    glPushMatrix();
    for (int i = 0; i < 10; i++)
    {
        glBegin(GL_LINE_STRIP); 
        a = myArray[(rand() % 2)];
        std::cout<<a;
        if(a == 0.1){
            glVertex2f(0,a);
            glVertex2f(a,a);
            glVertex2f(a,0);
        }else{
            glVertex2f(0.1,a);
            glVertex2f(a,a);
            glVertex2f(a,0.1);}
        glEnd();
        glTranslatef(0.1,0,0);
    }
    glPopMatrix();
    glTranslatef(0,0.1,0);
}
glFlush();}

Upvotes: 0

Views: 4801

Answers (1)

rems4e
rems4e

Reputation: 3172

    a = myArray[(rand() % 2)];

Here is your problem : a is an int, myArray contains only doubles < 0.5, so the affectation means rounding, so all your results are 0. You have to change the type of a to double.

Upvotes: 2

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