/*
 *  gencmap.c
 *  ---------
 *  Generate a colour map using some technique, and
 *  display it in a window.
 */

#include <graphapp.h>

window  w = NULL;       /* the main window */
drawing d = NULL;       /* where to draw the colours */
label val = NULL;       /* to display the colour value */
menuitem last_checked;

int width  = 256;       /* size of the drawing */
int height = 256;

int cmap_size = 0;	/* size of the colour map */
rgb cmap[256];          /* the colour map */


/* initialise the colour map with values */
void init_cmap_white(void)
{
	int i;
	for (i=0; i<256; i++)
		cmap[i] = White;
	cmap_size = 256;
}

void init_grey_cmap(int value)
{
	int i, level;

	for (i=0; i<value; i++) {
		level = (long) 255 * i / (value-1);
		cmap[i] = rgb(level, level, level);
	}
	cmap_size = value;
}

void choose_greys(menuitem m)
{
	char *result;
	char s[8];
	int value;

	sprintf(s, "%d", cmap_size);
	result = askstring("How many levels of grey?", s);

	if (result)
		value = atoi(result);
	else
		return;

	if (value < 0)   value = 0;
	if (value > 256) value = 256;

	init_grey_cmap(value);
	redraw(d);
}

void init_cmap_flesh(void)
{
	int i;
	long r, g, b;

	r = 115;
	g = 100;
	b = 100;
	for (i=0; i<16; i++) {
		cmap[i] = rgb(r,g,b);
		r = r + 13; if (r > 255) r = 255;
		g = g + 9;  if (g > 255) g = 255;
		b = b + 5;  if (b > 255) b = 255; 
	}
	cmap_size = 16;
}

void init_cmap_2x2x2(void)
{
	long r, g, b;

	for (r=0; r < 2; r++)
	  for (g=0; g < 2; g++)
	    for(b=0; b < 2; b++)
		cmap[r*4+g*2+b] = rgb(255*r,255*g,255*b);
	cmap_size = 2*2*2;
}

void init_cmap_3x3x3(void)
{
	long r, g, b;

	for (r=0; r < 3; r++)
	  for (g=0; g < 3; g++)
	    for(b=0; b < 3; b++)
		cmap[r*9+g*3+b] = rgb(255*r/2,255*g/2,255*b/2);
	cmap_size = 3*3*3;
}

void init_cmap_4x4x4(void)
{
	long r, g, b;

	for (r=0; r < 4; r++)
	  for (g=0; g < 4; g++)
	    for(b=0; b < 4; b++)
		cmap[r*16+g*4+b] = rgb(255*r/3,255*g/3,255*b/3);
	cmap_size = 4*4*4;
}

void init_cmap_5x5x5(void)
{
	long r, g, b;

	for (r=0; r < 5; r++)
	  for (g=0; g < 5; g++)
	    for(b=0; b < 5; b++)
		cmap[r*25+g*5+b] = rgb(255*r/4,255*g/4,255*b/4);
	cmap_size = 5*5*5;
}

void init_cmap_6x6x6(void)
{
	long r, g, b;

	for (r=0; r < 6; r++)
	  for (g=0; g < 6; g++)
	    for(b=0; b < 6; b++)
		cmap[r*36+g*6+b] = rgb(255*r/5,255*g/5,255*b/5);
	cmap_size = 6*6*6;
}

void init_cmap_6x6x7(void)
{
	long r, g, b;

	for (r=0; r < 6; r++)
	  for (g=0; g < 6; g++)
	    for(b=0; b < 7; b++)
		cmap[r*42+g*7+b] = rgb(255*r/5,255*g/5,255*b/6);
	cmap_size = 6*6*7;
}

void init_cmap_6x7x6(void)
{
	long r, g, b;

	for (r=0; r < 6; r++)
	  for (g=0; g < 7; g++)
	    for(b=0; b < 6; b++)
		cmap[r*42+g*6+b] = rgb(255*r/5,255*g/6,255*b/5);
	cmap_size = 6*7*6;
}

void init_cmap_7x6x6(void)
{
	long r, g, b;

	for (r=0; r < 7; r++)
	  for (g=0; g < 6; g++)
	    for(b=0; b < 6; b++)
		cmap[r*36+g*6+b] = rgb(255*r/6,255*g/5,255*b/5);
	cmap_size = 7*6*6;
}

void init_cmap_7x7x5(void)
{
	long r, g, b;

	for (r=0; r < 7; r++)
	  for (g=0; g < 7; g++)
	    for(b=0; b < 5; b++)
		cmap[r*35+g*5+b] = rgb(255*r/6,255*g/6,255*b/4);
	cmap_size = 7*7*5;
}

void init_cmap_7x5x7(void)
{
	long r, g, b;

	for (r=0; r < 7; r++)
	  for (g=0; g < 5; g++)
	    for(b=0; b < 7; b++)
		cmap[r*35+g*7+b] = rgb(255*r/6,255*g/4,255*b/6);
	cmap_size = 7*5*7;
}

void init_cmap_5x7x7(void)
{
	long r, g, b;

	for (r=0; r < 5; r++)
	  for (g=0; g < 7; g++)
	    for(b=0; b < 7; b++)
		cmap[r*49+g*7+b] = rgb(255*r/4,255*g/6,255*b/6);
	cmap_size = 5*7*7;
}

void init_cmap_8x8x4(void)
{
	long r, g, b;

	for (r=0; r < 8; r++)
	  for (g=0; g < 8; g++)
	    for(b=0; b < 4; b++)
		cmap[r*32+g*4+b] = rgb(255*r/7,255*g/7,255*b/3);
	cmap_size = 8*8*4;
}

void init_cmap_8x4x8(void)
{
	long r, g, b;

	for (r=0; r < 8; r++)
	  for (g=0; g < 4; g++)
	    for(b=0; b < 8; b++)
		cmap[r*32+g*8+b] = rgb(255*r/7,255*g/3,255*b/7);
	cmap_size = 8*4*8;
}

void init_cmap_4x8x8(void)
{
	long r, g, b;

	for (r=0; r < 4; r++)
	  for (g=0; g < 8; g++)
	    for(b=0; b < 8; b++)
		cmap[r*64+g*8+b] = rgb(255*r/3,255*g/7,255*b/7);
	cmap_size = 4*8*8;
}

void change_cmap(menuitem m)
{
	uncheck(last_checked);
	check(m);
	last_checked = m;

	init_cmap_white();

	switch(getvalue(m)) {
		case 0:   init_cmap_white(); break;
		case 216: init_cmap_flesh(); break;

		case 2:   init_cmap_2x2x2(); break;
		case 3:   init_cmap_3x3x3(); break;
		case 4:   init_cmap_4x4x4(); break;
		case 5:   init_cmap_5x5x5(); break;
		case 6:   init_cmap_6x6x6(); break;

		case 667: init_cmap_6x6x7(); break;
		case 676: init_cmap_6x7x6(); break;
		case 766: init_cmap_7x6x6(); break;

		case 775: init_cmap_7x7x5(); break;
		case 757: init_cmap_7x5x7(); break;
		case 577: init_cmap_5x7x7(); break;

		case 884: init_cmap_8x8x4(); break;
		case 848: init_cmap_8x4x8(); break;
		case 488: init_cmap_4x8x8(); break;

		default:  init_cmap_white(); break;
	}
	redraw(d);
}

/* draw the colour map on the drawing area */
void draw_cmap(drawing d, rect r)
{
	int i, x, y;
	int linestep = (width/16);
	rect bounds;

	for (i=0; i < cmap_size; i++) {
		x = i % linestep;
		y = i / linestep;
		bounds = rect(x*16, y*16, 16, 16);
		setcolour(LightGrey);
		drawrect(bounds);
		setcolour(cmap[i]);
		fillrect(insetr(bounds,1));
	}
}

/* handle a mouse movement over the window */
void clear_colour_display(drawing d, int buttons, point p)
{
	/* clear the display of colour component values */
	settext(val, "");
}

/* handle a mouse movement over the drawing area */
void set_colour_display(drawing d, int buttons, point p)
{
	int colour;
	char str[40];
	int linestep = (width/16);

	colour = (p.x / 16) + linestep * (p.y / 16);
	if (colour > 255) colour = 255;
	if (colour < 0 )  colour = 0;

	sprintf(str, "0x%-08.8lX", cmap[colour]);
	settext(val, str);
}

/* the window's redraw function merely draws a box around the edge */
void draw_window(window w, rect r)
{
	setcolour(Black);
	drawrect(insetr(r,5));
}

/* handle a window resize */
void resize_window(window w, rect r)
{
	width = r.width-20;
	height = r.height-65;
	resize(d, rect(r.x+10,r.y+10,width,height));
	resize(val, rect(10,height+20,120,35));
}

/* quit the program */
void quit(menuitem m)
{
	exitapp();
}

/* starting point of the program */
void main(void)
{
	menuitem m;

	/* create the window */
	w = newwindow("Explore a Colour Map",
			rect(50,50,width+20,height+65),
			StandardWindow + Menubar + UsePalette);
	setredraw(w, draw_window);
	setresize(w, resize_window);
	//setmousemove(w, clear_colour_display);

	/* create the menubar */
	newmenubar(NULL);

	newmenu("File");
	newmenuitem("Quit", 'Q', quit);

	newmenu("Cubes");
	setvalue(newmenuitem("2x2x2", 0, change_cmap), 2);
	setvalue(newmenuitem("3x3x3", 0, change_cmap), 3);
	setvalue(newmenuitem("4x4x4", 0, change_cmap), 4);
	setvalue(newmenuitem("5x5x5", 0, change_cmap), 5);
	setvalue(newmenuitem("6x6x6", 0, change_cmap), 6);

	newmenu("Prisms");
	setvalue(newmenuitem("6x6x7", 0, change_cmap), 667);
	setvalue(newmenuitem("6x7x6", 0, change_cmap), 676);
	setvalue(newmenuitem("7x6x6", 0, change_cmap), 766);

	setvalue(newmenuitem("7x7x5", 0, change_cmap), 775);
	setvalue(newmenuitem("7x5x7", 0, change_cmap), 757);
	setvalue(newmenuitem("5x7x7", 0, change_cmap), 577);

	setvalue(newmenuitem("8x8x4", 0, change_cmap), 884);
	setvalue(newmenuitem("8x4x8", 0, change_cmap), 848);
	setvalue(m = newmenuitem("4x8x8", 0, change_cmap), 488);
	check(m);
	last_checked = m;

	newmenu("Ramps");
	newmenuitem("Greys...", 0, choose_greys);
	setvalue(newmenuitem("Flesh tones", 0, change_cmap), 216);

	/* create the drawing area and set a mouse movement callback */
	d = newdrawing(rect(10,10,width,height), draw_cmap);
	setmousemove(d, set_colour_display);

	/* create the colour display label */
	val = newlabel("", rect(10,height+20,120,30), AlignLeft);

	/* initialise the colour map */
	init_cmap_4x8x8();

	/* show the window */
	show(w);
}