/********************************************************************************


    AMERICAN POKER 2 - VIDEO HARDWARE
    ---------------------------------

    Company:    Novomatic.
    Year:       1990.

    Driver by Roberto Fresca, with a lot of help of Grull Osgo.
    Based on a preliminary work of Curt Coder.


    --- Supported Sets ---

    Set Name | Relation | Description
    ---------+----------+------------------------------------
    ampoker2 |  parent  |  American Poker II.
    ampkr2b1 |  clone   |  American Poker II (bootleg, set 1).
    ampkr2b2 |  clone   |  American Poker II (bootleg, set 2).
    ampkr2b3 |  clone   |  American Poker II (bootleg, set 3).
    ampkr228 |  clone   |  American Poker II (iamp2 v28).
    pkrdewin |  clone   |  Poker De Win.
    ampkr95  |  clone   |  American Poker 95.
    videomat |  clone   |  Videomat (polish bootleg).
    sigmapkr |  parent  |  Sigma Poker.
    sigma2k  |  parent  |  Sigma Poker 2000.


*********************************************************************************


    Resistor Network
    ----------------

    The following diagram is related to taiwanese and argentine PCBs.


    82S147AN
   +---------+
   |         |    470
   | O1-Pin06|---/\/\/\----+---> BLUE
   |         |    220      |
   | O2-Pin07|---/\/\/\----+
   |         |    1K
   | O3-Pin08|---/\/\/\----+---> GREEN
   |         |    470      |
   | O4-Pin09|---/\/\/\----+
   |         |    220      |
   | O5-Pin11|---/\/\/\----+
   |         |    1K
   | O6-Pin12|---/\/\/\----+---> RED
   |         |    470      |
   | O7-Pin13|---/\/\/\----+
   |         |    220      |
   | O8-Pin14|---/\/\/\----+
   |         |
   +---------+


   All colors are directly routed to the edge connector.
   There are not pull-up or pull-down resistors.


********************************************************************************/


#include "driver.h"
#include "video/resnet.h"

static tilemap *bg_tilemap;


PALETTE_INIT( ampoker2 )
{
/*    - bits -
      76543210
      RRRGGGBB
*/
	int i;
	static const int resistances_rg[3] = { 1000, 470, 220 };
	static const int resistances_b [2] = { 470, 220 };
	double weights_r[3], weights_g[3], weights_b[2];

	compute_resistor_weights(0,	255,	-1.0,
			3,	resistances_rg,	weights_r,	0,	0,
			3,	resistances_rg,	weights_g,	0,	0,
			2,	resistances_b,	weights_b,	0,	0);


	for (i = 0; i < machine->config->total_colors; i++)
	{
		int bit0, bit1, bit2, r, g, b;

		/* blue component */
		bit0 = (color_prom[i] >> 0) & 0x01;
		bit1 = (color_prom[i] >> 1) & 0x01;
		b = combine_2_weights(weights_b, bit0, bit1);
		/* green component */
		bit0 = (color_prom[i] >> 2) & 0x01;
		bit1 = (color_prom[i] >> 3) & 0x01;
		bit2 = (color_prom[i] >> 4) & 0x01;
		g = combine_3_weights(weights_g, bit0, bit1, bit2);
		/* red component */
		bit0 = (color_prom[i] >> 5) & 0x01;
		bit1 = (color_prom[i] >> 6) & 0x01;
		bit2 = (color_prom[i] >> 7) & 0x01;
		r = combine_3_weights(weights_r, bit0, bit1, bit2);

		palette_set_color(machine,i,MAKE_RGB(r,g,b));
	}
}

WRITE8_HANDLER( ampoker2_videoram_w )
{
	videoram[offset] = data;
	tilemap_mark_tile_dirty(bg_tilemap, offset / 2);
}

static TILE_GET_INFO( get_bg_tile_info )
{
	int offs = tile_index * 2;
	int attr = videoram[offs + 1];
	int code = videoram[offs];
	int color = attr;
	code = code + (256 * (color & 0x03));   /* code = color.bit1 + color.bit0 + code */
	color = color >> 1;	                    /* color = color - bit0 (bit1..bit7) */

	SET_TILE_INFO(0, code, color, 0);
}

static TILE_GET_INFO( s2k_get_bg_tile_info )
{
	int offs = tile_index * 2;
	int attr = videoram[offs + 1];
	int code = videoram[offs];
	int color = attr;
	code = code + (256 * (color & 0x0f));	/* the game uses 2 extra bits */
	color = color >> 1;

	SET_TILE_INFO(0, code, color, 0);
}

VIDEO_START(ampoker2)
{
	bg_tilemap = tilemap_create(machine, get_bg_tile_info, tilemap_scan_rows,
		 8, 8, 64, 32);
}

VIDEO_START(sigma2k)
{
	bg_tilemap = tilemap_create(machine, s2k_get_bg_tile_info, tilemap_scan_rows,
		 8, 8, 64, 32);
}

VIDEO_UPDATE(ampoker2)
{
	tilemap_draw(bitmap, cliprect, bg_tilemap, 0, 0);
	return 0;
}
