/*************************************************************************** video.c Functions to emulate the video hardware of the machine. ***************************************************************************/ #include "emu.h" #include "video/resnet.h" #include "includes/shaolins.h" /*************************************************************************** Convert the color PROMs into a more useable format. Shao-lin's Road has three 256x4 palette PROMs (one per gun) and two 256x4 lookup table PROMs (one for characters, one for sprites). I don't know for sure how the palette PROMs are connected to the RGB output, but it's probably the usual: bit 3 -- 220 ohm resistor -- RED/GREEN/BLUE -- 470 ohm resistor -- RED/GREEN/BLUE -- 1 kohm resistor -- RED/GREEN/BLUE bit 0 -- 2.2kohm resistor -- RED/GREEN/BLUE ***************************************************************************/ PALETTE_INIT( shaolins ) { static const int resistances[4] = { 2200, 1000, 470, 220 }; double rweights[4], gweights[4], bweights[4]; int i; /* compute the color output resistor weights */ compute_resistor_weights(0, 255, -1.0, 4, resistances, rweights, 470, 0, 4, resistances, gweights, 470, 0, 4, resistances, bweights, 470, 0); /* allocate the colortable */ machine.colortable = colortable_alloc(machine, 0x100); /* create a lookup table for the palette */ for (i = 0; i < 0x100; i++) { int bit0, bit1, bit2, bit3; int r, g, b; /* red component */ bit0 = (color_prom[i + 0x000] >> 0) & 0x01; bit1 = (color_prom[i + 0x000] >> 1) & 0x01; bit2 = (color_prom[i + 0x000] >> 2) & 0x01; bit3 = (color_prom[i + 0x000] >> 3) & 0x01; r = combine_4_weights(rweights, bit0, bit1, bit2, bit3); /* green component */ bit0 = (color_prom[i + 0x100] >> 0) & 0x01; bit1 = (color_prom[i + 0x100] >> 1) & 0x01; bit2 = (color_prom[i + 0x100] >> 2) & 0x01; bit3 = (color_prom[i + 0x100] >> 3) & 0x01; g = combine_4_weights(gweights, bit0, bit1, bit2, bit3); /* blue component */ bit0 = (color_prom[i + 0x200] >> 0) & 0x01; bit1 = (color_prom[i + 0x200] >> 1) & 0x01; bit2 = (color_prom[i + 0x200] >> 2) & 0x01; bit3 = (color_prom[i + 0x200] >> 3) & 0x01; b = combine_4_weights(bweights, bit0, bit1, bit2, bit3); colortable_palette_set_color(machine.colortable, i, MAKE_RGB(r, g, b)); } /* color_prom now points to the beginning of the lookup table,*/ color_prom += 0x300; /* characters use colors 0x10-0x1f of each 0x20 color bank, while sprites use colors 0-0x0f */ for (i = 0; i < 0x200; i++) { int j; for (j = 0; j < 8; j++) { UINT8 ctabentry = (j << 5) | ((~i & 0x100) >> 4) | (color_prom[i] & 0x0f); colortable_entry_set_value(machine.colortable, ((i & 0x100) << 3) | (j << 8) | (i & 0xff), ctabentry); } } } WRITE8_HANDLER( shaolins_videoram_w ) { shaolins_state *state = space->machine().driver_data(); state->m_videoram[offset] = data; tilemap_mark_tile_dirty(state->m_bg_tilemap, offset); } WRITE8_HANDLER( shaolins_colorram_w ) { shaolins_state *state = space->machine().driver_data(); state->m_colorram[offset] = data; tilemap_mark_tile_dirty(state->m_bg_tilemap, offset); } WRITE8_HANDLER( shaolins_palettebank_w ) { shaolins_state *state = space->machine().driver_data(); if (state->m_palettebank != (data & 0x07)) { state->m_palettebank = data & 0x07; tilemap_mark_all_tiles_dirty_all(space->machine()); } } WRITE8_HANDLER( shaolins_scroll_w ) { shaolins_state *state = space->machine().driver_data(); int col; for (col = 4; col < 32; col++) tilemap_set_scrolly(state->m_bg_tilemap, col, data + 1); } WRITE8_HANDLER( shaolins_nmi_w ) { shaolins_state *state = space->machine().driver_data(); state->m_nmi_enable = data; if (flip_screen_get(space->machine()) != (data & 0x01)) { flip_screen_set(space->machine(), data & 0x01); tilemap_mark_all_tiles_dirty_all(space->machine()); } } static TILE_GET_INFO( get_bg_tile_info ) { shaolins_state *state = machine.driver_data(); int attr = state->m_colorram[tile_index]; int code = state->m_videoram[tile_index] + ((attr & 0x40) << 2); int color = (attr & 0x0f) + 16 * state->m_palettebank; int flags = (attr & 0x20) ? TILE_FLIPY : 0; SET_TILE_INFO(0, code, color, flags); } VIDEO_START( shaolins ) { shaolins_state *state = machine.driver_data(); state->m_bg_tilemap = tilemap_create(machine, get_bg_tile_info, tilemap_scan_rows, 8, 8, 32, 32); tilemap_set_scroll_cols(state->m_bg_tilemap, 32); } static void draw_sprites(running_machine &machine, bitmap_t *bitmap, const rectangle *cliprect) { shaolins_state *state = machine.driver_data(); UINT8 *spriteram = state->m_spriteram; int offs; for (offs = state->m_spriteram_size - 32; offs >= 0; offs -= 32 ) /* max 24 sprites */ { if (spriteram[offs] && spriteram[offs + 6]) /* stop rogue sprites on high score screen */ { int code = spriteram[offs + 8]; int color = (spriteram[offs + 9] & 0x0f) | (state->m_palettebank << 4); int flipx = !(spriteram[offs + 9] & 0x40); int flipy = spriteram[offs + 9] & 0x80; int sx = 240 - spriteram[offs + 6]; int sy = 248 - spriteram[offs + 4]; if (flip_screen_get(machine)) { sx = 240 - sx; sy = 248 - sy; flipx = !flipx; flipy = !flipy; } drawgfx_transmask(bitmap, cliprect,machine.gfx[1], code, color, flipx, flipy, sx, sy, colortable_get_transpen_mask(machine.colortable, machine.gfx[1], color, state->m_palettebank << 5)); } } } SCREEN_UPDATE( shaolins ) { shaolins_state *state = screen->machine().driver_data(); tilemap_draw(bitmap, cliprect, state->m_bg_tilemap, 0, 0); draw_sprites(screen->machine(), bitmap, cliprect); return 0; }