/* examples/canvas/xi.c */

#include <helium.h>

#define XMAX 180
#define YMAX 220

He_node *princ, *canvas;
XImage *xi;

void init_xi ()
{
    int x, y;

    /* Création */
    xi = HeCreateXi (XMAX, YMAX);
    if (xi == NULL) return;

    /* Calcul */
    for (y = 0; y < YMAX; y++)
    for (x = 0; x < XMAX; x++) {
        Uchar R = x, G = 255-x, B = y;
        HeSetXiPixel (xi, y*XMAX+x, R, G, B);
    }
}

void canvas_repaint_proc (He_node *hn, Window win)
{
    int i, j;

    /* Affichage multiple instantané */
    for (i = 0; i <= HeGetWidth (hn)/XMAX; i++)
    for (j = 0; j <= HeGetHeight(hn)/YMAX; j++)
        HePutXi (win, he_gc, xi, i*XMAX, j*YMAX);
}

int main (int argc, char *argv[])
{
    HeInit (&argc, &argv);

    princ = HeCreateFrame();
    HeSetFrameLabel (princ, "XImage");

    canvas = HeCreateCanvas (princ);
    HeSetCanvasRepaintProc (canvas, canvas_repaint_proc);
    HeSetWidth (canvas, 500); HeSetHeight (canvas, 500);
    init_xi();

    HeFit (princ);

    return HeMainLoop (princ);
}