/*
	sines.c
 
	Author Jani Kniivilä

	Compile with: gcc -o sines sines.c -lSDL -lpthread -ltSGGL -lm
*/

#include <stdio.h>
#include <stdlib.h>
#include <math.h>

#include <SDL/SDL.h>
#include <tSGGL/SGGL.h>

SDL_Surface	*surface;
gfx_image_t	*output;
gfx_image_t	*background;

#define	WIDTH	640
#define	HEIGHT	480

#define	SINE_HEIGHT	60

gfx_vline_t	*vlines[3];
gfx_color_t	*red, *green, *blue;

const float	my_pi = 3.141593;

int	fx_init()
{
	int		i, x, y;
	gfx_color_t	color;

	if (SDL_Init(SDL_INIT_VIDEO) < 0) return -1;
	atexit(SDL_Quit);

	surface = SDL_SetVideoMode(WIDTH, HEIGHT, 16, SDL_SWSURFACE);
	if (!surface) return -2;

	output = gfx_create_null_image(WIDTH, HEIGHT);	/* create an image without pixel-data */
	if (!output) return -3;
	output->data = (Uint16 *) surface->pixels;	/* redirect the pixels to "screen" */

	vlines[0] = (gfx_vline_t *) calloc(output->width, sizeof(gfx_vline_t));
	if (!vlines[0]) return -4;
	vlines[1] = (gfx_vline_t *) calloc(output->width, sizeof(gfx_vline_t));
	if (!vlines[1]) return -5;
	vlines[2] = (gfx_vline_t *) calloc(output->width, sizeof(gfx_vline_t));
	if (!vlines[2]) return -6;

	red = gfx_alloc_color(192, 32, 32);
	green = gfx_alloc_color(32, 192, 32);
	blue = gfx_alloc_color(32, 32, 192);

	for (i = 0; i < output->width; i++)
	{
		vlines[0][i].x = i;
		vlines[1][i].x = i;
		vlines[2][i].x = i;

		vlines[0][i].color = red;
		vlines[1][i].color = green;
		vlines[2][i].color = blue;
	}

	background = gfx_create_empty_image(WIDTH, HEIGHT);
	if (!background) return -10;

	gfx_set_color(&color, 8, 8, 8);

	for (i = 0; i < 10000; i++)
	{
		x = -10 + 5 * (rand() % ((output->width + 20)/5));
		y = -10 + 5 * (rand() % ((output->height + 20)/5));
		gfx_slow_addrect(x, y, x+29, y+29, &color, background);
	}

	return 0;
}

void	fx_shutdown()
{
	free(vlines[0]);
	free(vlines[1]);
	free(vlines[2]);
	gfx_dispose_color(red);
	gfx_dispose_color(green);
	gfx_dispose_color(blue);
	gfx_dispose_image(background);
	free(output);
}

int	fx_draw_frame()
{
	static float angle = 0;
	int	i;

	for (i = 0; i < output->width; i++)
	{
		vlines[0][i].y1 = 200 + sin(angle + i*my_pi/233.0) * (75 + cos(angle + i*my_pi/131.3) * 150);
		vlines[0][i].y2 = vlines[0][i].y1 + SINE_HEIGHT-1;

		vlines[1][i].y1 = 250 + sin(angle + i*my_pi/129.0) * (75 + cos(angle + i*my_pi/300.3) * 150);
		vlines[1][i].y2 = vlines[1][i].y1 + SINE_HEIGHT-1;

		vlines[2][i].y1 = 300 + sin(angle + i*my_pi/500.1) * (75 + cos(angle + i*my_pi/400.3) * 150);
		vlines[2][i].y2 = vlines[2][i].y1 + SINE_HEIGHT-1;
	}

	if (SDL_MUSTLOCK(surface))
		SDL_LockSurface(surface);

	gfx_copy(output, background);

	gfx_slow_addvlines(vlines[0], output->width, output);
	gfx_slow_addvlines(vlines[1], output->width, output);
	gfx_slow_addvlines(vlines[2], output->width, output);

	if (SDL_MUSTLOCK(surface))
		SDL_UnlockSurface(surface);

	SDL_Flip(surface);

	angle += my_pi / 45.0;

	return 0;
}

int	main()
{
	SDL_Event	event;
	int		i, done = 0;

	i = fx_init();
	if (i) return i;

	while (!done)
	{
		fx_draw_frame();

		while (SDL_PollEvent(&event))
		{
			switch (event.type)
			{
				case SDL_QUIT:
				case SDL_KEYDOWN:
				case SDL_MOUSEBUTTONDOWN:
					done = 1;
			}
		}
	}

	fx_shutdown();

	return 0;
}