//hitKeyM
//  Drawing a circle at the position of the pointer when key 'A' is hit.
// T. Kosaka CS TNCT 2001

#include <stdio.h>
#include <math.h>
#include <GL/glut.h>
#include "drawShape2D.h"

#ifndef M_PI
#define M_PI 3.141592653589793
#endif

void userdraw(void);

void display(void)
{
    glClear( GL_COLOR_BUFFER_BIT);
    userdraw();
    glutSwapBuffers();
}

unsigned int GlobalTick[40]={
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000,
    1000,1000,1000,1000,1000
};
point2D_t CurrentPoint[40];

void onKeyboard(unsigned char key, int x, int y_inv)
{
    int y=480-y_inv-1;  // device coordinate -> view coordinate
    int k;
    switch (key) {
    case 'A':
    case 'a':
        for (k=0;k<40;k++) {
            if (400<GlobalTick[k]) {
                GlobalTick[k]=10;
                CurrentPoint[k].x=x;
                CurrentPoint[k].y=y;
                break;
            }
        }
        break;
    default:
        break;
    }
}

void userdraw(void)
{
    float r;
    int num;
    int i,k;
    color_t col;
    point2D_t p[600];
    for (k=0;k<40;k++) {
        if (GlobalTick[k]<400) {
            r=GlobalTick[k];
            num=GlobalTick[k]/20+30;
            for (i=0;i<num;i++) {
                p[i].x=r*cos(2.*M_PI*i/num)+CurrentPoint[k].x;
                p[i].y=r*sin(2.*M_PI*i/num)+CurrentPoint[k].y;
            }
            col.r=((int)CurrentPoint[k].x%256)/128.0+0.2;
            col.g=((int)CurrentPoint[k].y%256)/128.0+0.2;
            col.b=((int)(CurrentPoint[k].x+CurrentPoint[k].y)%256)/128.0+0.2;
            setColor(col);
            drawPolygon(p,num);
        }
        GlobalTick[k]++;
        if (50000<GlobalTick[k]) GlobalTick[k]=1000;
    }
}

int main(int argc, char **argv)
{
    glutInit(&argc,argv);
    glutInitDisplayMode ( GLUT_DOUBLE | GLUT_RGB );
    glutInitWindowPosition(100,100);
    glutInitWindowSize(640,480);
    glutCreateWindow ("hitKeyM  !!! Push 'A' key with the mouse moving. !!!");
    glClearColor(0.0, 0.0, 0.0, 0.0);
    gluOrtho2D(0., 640., 0., 480.0);
      // Define the dimensions of the Orthographic Viewing Volume
    glutIdleFunc(display); // idle event call back
    glutDisplayFunc(display);
    glutKeyboardFunc(onKeyboard);   // keyboard event call back
    glutMainLoop();
    return 0;
}