/******************************************************************************
 *
 * vector.c
 *
 *
 * Copyright Nicola Salmoria and the MAME Team
 *
 *        anti-alias code by Andrew Caldwell
 *        (still more to add)
 *
 * 040227 Fixed miny clip scaling which was breaking in mhavoc. AREK
 * 010903 added support for direct RGB modes MLR
 * 980611 use translucent vectors. Thanks to Peter Hirschberg
 *        and Neil Bradley for the inspiration. BW
 * 980307 added cleverer dirty handling. BW, ASG
 *        fixed antialias table .ac
 * 980221 rewrote anti-alias line draw routine
 *        added inline assembly multiply fuction for 8086 based machines
 *        beam diameter added to draw routine
 *        beam diameter is accurate in anti-alias line draw (Tcosin)
 *        flicker added .ac
 * 980203 moved LBO's routines for drawing into a buffer of vertices
 *        from avgdvg.c to this location. Scaling is now initialized
 *        by calling vector_init(...). BW
 * 980202 moved out of msdos.c ASG
 * 980124 added anti-alias line draw routine
 *        modified avgdvg.c and sega.c to support new line draw routine
 *        added two new tables Tinten and Tmerge (for 256 color support)
 *        added find_color routine to build above tables .ac
 *
 **************************************************************************** */

#include "emu.h"
#include "emuopts.h"
#include "rendutil.h"
#include "vector.h"



#define VECTOR_WIDTH_DENOM			512


#define MAX_POINTS	10000

#define VECTOR_TEAM \
	"-* Vector Heads *-\n" \
	"Brad Oliver\n" \
	"Aaron Giles\n" \
	"Bernd Wiebelt\n" \
	"Allard van der Bas\n" \
	"Al Kossow (VECSIM)\n" \
	"Hedley Rainnie (VECSIM)\n" \
	"Eric Smith (VECSIM)\n" \
	"Neil Bradley (technical advice)\n" \
	"Andrew Caldwell (anti-aliasing)\n" \
	"- *** -\n"

#if 0

#define TEXTURE_LENGTH_BUCKETS		32
#define TEXTURE_INTENSITY_BUCKETS	4
#define TEXTURE_WIDTH				16

#define MAX_INTENSITY				2
#define VECTOR_BLEED				(0.25f)
#define VECTOR_INT_SCALE			(255.0f * 1.5f)


typedef struct _vector_texture vector_texture;
struct _vector_texture
{
	render_texture *	texture;
	bitmap_t *			bitmap;
};

static vector_texture *vectortex[TEXTURE_INTENSITY_BUCKETS][TEXTURE_LENGTH_BUCKETS];


static render_texture *get_vector_texture(float dx, float dy, float intensity)
{
	float length = sqrt(dx * dx + dy * dy);
	int lbucket = length * (float)TEXTURE_LENGTH_BUCKETS;
	int ibucket = (intensity / (float)MAX_INTENSITY) * (float)TEXTURE_INTENSITY_BUCKETS;
	vector_texture *tex;
	int height, x, y;
	float totalint;

	if (lbucket > TEXTURE_LENGTH_BUCKETS)
		lbucket = TEXTURE_LENGTH_BUCKETS;
	if (ibucket > TEXTURE_INTENSITY_BUCKETS)
		ibucket = TEXTURE_INTENSITY_BUCKETS;

	tex = &vectortex[ibucket][lbucket];
	if (tex->texture != NULL)
		return tex->texture;

	height = lbucket * VECTOR_WIDTH_DENOM / TEXTURE_LENGTH_BUCKETS;
	tex->bitmap = global_alloc(bitmap_t(TEXTURE_WIDTH, height, BITMAP_FORMAT_ARGB32));
	bitmap_fill(tex->bitmap, NULL, MAKE_ARGB(0xff,0xff,0xff,0xff));

	totalint = 1.0f;
	for (x = TEXTURE_WIDTH / 2 - 1; x >= 0; x--)
	{
		int intensity = (int)(totalint * (1.0f - VECTOR_BLEED) * VECTOR_INT_SCALE);
		intensity = MIN(255, intensity);
		totalint -= (float)intensity * (1.0f / VECTOR_INT_SCALE);

		for (y = 0; y < height; y++)
		{
			UINT32 *pix;

			pix = (UINT32 *)bitmap->base + y * bitmap->rowpixels + x;
			*pix = MAKE_ARGB((RGB_ALPHA(*pix) * intensity) >> 8,0xff,0xff,0xff);

			pix = (UINT32 *)bitmap->base + y * bitmap->rowpixels + (TEXTURE_WIDTH - 1 - x);
			*pix = MAKE_ARGB((RGB_ALPHA(*pix) * intensity) >> 8,0xff,0xff,0xff);
		}
	}

	tex->texture = render_texture_create();
	return tex->texture;
}

#endif

#define VCLEAN  0
#define VDIRTY  1
#define VCLIP   2

/* The vertices are buffered here */
typedef struct
{
	int x; int y;
	rgb_t col;
	int intensity;
	int arg1; int arg2; /* start/end in pixel array or clipping info */
	int status;         /* for dirty and clipping handling */
} point;



UINT8 *vectorram;
size_t vectorram_size;

static int flicker;                              /* beam flicker value     */
static float flicker_correction = 0.0f;

static float beam_width;

static point *vector_list;
static int vector_index;


void vector_set_flicker(float _flicker)
{
	flicker_correction = _flicker;
	flicker = (int)(flicker_correction * 2.55);
}

float vector_get_flicker(void)
{
	return flicker_correction;
}

void vector_set_beam(float _beam)
{
	beam_width = _beam;
}

float vector_get_beam(void)
{
	return beam_width;
}

/*
 * Initializes vector game video emulation
 */

VIDEO_START( vector )
{
	beam_width = options_get_float(machine->options(), OPTION_BEAM);

	/* Grab the settings for this session */
	vector_set_flicker(options_get_float(machine->options(), OPTION_FLICKER));

	vector_index = 0;

	/* allocate memory for tables */
	vector_list = auto_alloc_array(machine, point, MAX_POINTS);
}


/*
 * Adds a line end point to the vertices list. The vector processor emulation
 * needs to call this.
 */
void vector_add_point (running_machine *machine, int x, int y, rgb_t color, int intensity)
{
	point *newpoint;

	if (intensity > 0xff)
		intensity = 0xff;

	if (flicker && (intensity > 0))
	{
		intensity += (intensity * (0x80-(mame_rand(machine)&0xff)) * flicker)>>16;
		if (intensity < 0)
			intensity = 0;
		if (intensity > 0xff)
			intensity = 0xff;
	}
	newpoint = &vector_list[vector_index];
	newpoint->x = x;
	newpoint->y = y;
	newpoint->col = color;
	newpoint->intensity = intensity;
	newpoint->status = VDIRTY; /* mark identical lines as clean later */

	vector_index++;
	if (vector_index >= MAX_POINTS)
	{
		vector_index--;
		logerror("*** Warning! Vector list overflow!\n");
	}
}

/*
 * Add new clipping info to the list
 */
void vector_add_clip (int x1, int yy1, int x2, int y2)
{
	point *newpoint;

	newpoint = &vector_list[vector_index];
	newpoint->x = x1;
	newpoint->y = yy1;
	newpoint->arg1 = x2;
	newpoint->arg2 = y2;
	newpoint->status = VCLIP;

	vector_index++;
	if (vector_index >= MAX_POINTS)
	{
		vector_index--;
		logerror("*** Warning! Vector list overflow!\n");
	}
}


/*
 * The vector CPU creates a new display list. We save the old display list,
 * but only once per refresh.
 */
void vector_clear_list (void)
{
	vector_index = 0;
}


VIDEO_UPDATE( vector )
{
	UINT32 flags = PRIMFLAG_ANTIALIAS(options_get_bool(screen->machine->options(), OPTION_ANTIALIAS) ? 1 : 0) | PRIMFLAG_BLENDMODE(BLENDMODE_ADD);
	const rectangle &visarea = screen->visible_area();
	float xscale = 1.0f / (65536 * (visarea.max_x - visarea.min_x));
	float yscale = 1.0f / (65536 * (visarea.max_y - visarea.min_y));
	float xoffs = (float)visarea.min_x;
	float yoffs = (float)visarea.min_y;
	point *curpoint;
	render_bounds clip;
	int lastx = 0, lasty = 0;
	int i;

	curpoint = vector_list;

	render_container_empty(render_container_get_screen(screen));
	render_screen_add_rect(screen, 0.0f, 0.0f, 1.0f, 1.0f, MAKE_ARGB(0xff,0x00,0x00,0x00), PRIMFLAG_BLENDMODE(BLENDMODE_ALPHA));

	clip.x0 = clip.y0 = 0.0f;
	clip.x1 = clip.y1 = 1.0f;

	for (i = 0; i < vector_index; i++)
	{
		render_bounds coords;

		if (curpoint->status == VCLIP)
		{
			coords.x0 = ((float)curpoint->x - xoffs) * xscale;
			coords.y0 = ((float)curpoint->y - yoffs) * yscale;
			coords.x1 = ((float)curpoint->arg1 - xoffs) * xscale;
			coords.y1 = ((float)curpoint->arg2 - yoffs) * yscale;

			clip.x0 = (coords.x0 > 0.0f) ? coords.x0 : 0.0f;
			clip.y0 = (coords.y0 > 0.0f) ? coords.y0 : 0.0f;
			clip.x1 = (coords.x1 < 1.0f) ? coords.x1 : 1.0f;
			clip.y1 = (coords.y1 < 1.0f) ? coords.y1 : 1.0f;
		}
		else
		{
			coords.x0 = ((float)lastx - xoffs) * xscale;
			coords.y0 = ((float)lasty - yoffs) * yscale;
			coords.x1 = ((float)curpoint->x - xoffs) * xscale;
			coords.y1 = ((float)curpoint->y - yoffs) * yscale;

			if (curpoint->intensity != 0)
				if (!render_clip_line(&coords, &clip))
					render_screen_add_line(screen, coords.x0, coords.y0, coords.x1, coords.y1,
							beam_width * (1.0f / (float)VECTOR_WIDTH_DENOM),
							(curpoint->intensity << 24) | (curpoint->col & 0xffffff),
							flags);

			lastx = curpoint->x;
			lasty = curpoint->y;
		}
		curpoint++;
	}
	return 0;
}
