diff options
Diffstat (limited to 'src/mame/video/atarig42.c')
-rw-r--r-- | src/mame/video/atarig42.c | 266 |
1 files changed, 266 insertions, 0 deletions
diff --git a/src/mame/video/atarig42.c b/src/mame/video/atarig42.c new file mode 100644 index 00000000000..b0f08f43825 --- /dev/null +++ b/src/mame/video/atarig42.c @@ -0,0 +1,266 @@ +/*************************************************************************** + + Atari G42 hardware + +***************************************************************************** + + MO data has 12 bits total: MVID0-11 + MVID9-11 form the priority + MVID0-9 form the color bits + + PF data has 13 bits total: PF.VID0-12 + PF.VID10-12 form the priority + PF.VID0-9 form the color bits + + Upper bits come from the low 5 bits of the HSCROLL value in alpha RAM + Playfield bank comes from low 2 bits of the VSCROLL value in alpha RAM + For GX2, there are 4 bits of bank + +****************************************************************************/ + + +#include "driver.h" +#include "machine/atarigen.h" +#include "atarig42.h" + + + +/************************************* + * + * Globals we own + * + *************************************/ + +UINT16 atarig42_playfield_base; +UINT16 atarig42_motion_object_base; +UINT16 atarig42_motion_object_mask; + + + +/************************************* + * + * Statics + * + *************************************/ + +static UINT16 current_control; +static UINT8 playfield_tile_bank; +static UINT8 playfield_color_bank; +static UINT16 playfield_xscroll; +static UINT16 playfield_yscroll; + + + +/************************************* + * + * Tilemap callbacks + * + *************************************/ + +static TILE_GET_INFO( get_alpha_tile_info ) +{ + UINT16 data = atarigen_alpha[tile_index]; + int code = data & 0xfff; + int color = (data >> 12) & 0x0f; + int opaque = data & 0x8000; + SET_TILE_INFO(1, code, color, opaque ? TILE_FORCE_LAYER0 : 0); +} + + +static TILE_GET_INFO( get_playfield_tile_info ) +{ + UINT16 data = atarigen_playfield[tile_index]; + int code = (playfield_tile_bank << 12) | (data & 0xfff); + int color = (atarig42_playfield_base >> 5) + ((playfield_color_bank << 3) & 0x18) + ((data >> 12) & 7); + SET_TILE_INFO(0, code, color, (data >> 15) & 1); + tileinfo->category = (playfield_color_bank >> 2) & 7; +} + + +static TILEMAP_MAPPER( atarig42_playfield_scan ) +{ + int bank = 1 - (col / (num_cols / 2)); + return bank * (num_rows * num_cols / 2) + row * (num_cols / 2) + (col % (num_cols / 2)); +} + + + +/************************************* + * + * Video system start + * + *************************************/ + +VIDEO_START( atarig42 ) +{ + static const struct atarirle_desc modesc = + { + REGION_GFX3,/* region where the GFX data lives */ + 256, /* number of entries in sprite RAM */ + 0, /* left clip coordinate */ + 0, /* right clip coordinate */ + + 0x000, /* base palette entry */ + 0x400, /* maximum number of colors */ + + {{ 0x7fff,0,0,0,0,0,0,0 }}, /* mask for the code index */ + {{ 0,0x03f0,0,0,0,0,0,0 }}, /* mask for the color */ + {{ 0,0,0xffc0,0,0,0,0,0 }}, /* mask for the X position */ + {{ 0,0,0,0xffc0,0,0,0,0 }}, /* mask for the Y position */ + {{ 0,0,0,0,0xffff,0,0,0 }}, /* mask for the scale factor */ + {{ 0x8000,0,0,0,0,0,0,0 }}, /* mask for the horizontal flip */ + {{ 0,0,0,0,0,0,0x00ff,0 }}, /* mask for the order */ + {{ 0,0x0e00,0,0,0,0,0,0 }}, /* mask for the priority */ + {{ 0 }} /* mask for the VRAM target */ + }; + struct atarirle_desc adjusted_modesc = modesc; + int i; + + /* blend the playfields and free the temporary one */ + atarigen_blend_gfx(machine, 0, 2, 0x0f, 0x30); + + /* initialize the playfield */ + atarigen_playfield_tilemap = tilemap_create(get_playfield_tile_info, atarig42_playfield_scan, TILEMAP_TYPE_PEN, 8,8, 128,64); + + /* initialize the motion objects */ + adjusted_modesc.palettebase = atarig42_motion_object_base; + for (i = 0; i < 8; i++) + adjusted_modesc.colormask.data[i] &= atarig42_motion_object_mask; + atarirle_init(0, &adjusted_modesc); + + /* initialize the alphanumerics */ + atarigen_alpha_tilemap = tilemap_create(get_alpha_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 8,8, 64,32); + tilemap_set_transparent_pen(atarigen_alpha_tilemap, 0); + + /* reset statics */ + current_control = 0; + playfield_tile_bank = 0; + playfield_color_bank = 0; + playfield_xscroll = 0; + playfield_yscroll = 0; +} + + + +/************************************* + * + * Periodic scanline updater + * + *************************************/ + +WRITE16_HANDLER( atarig42_mo_control_w ) +{ + logerror("MOCONT = %d (scan = %d)\n", data, video_screen_get_vpos(0)); + + /* set the control value */ + COMBINE_DATA(¤t_control); +} + + +void atarig42_scanline_update(running_machine *machine, int scrnum, int scanline) +{ + UINT16 *base = &atarigen_alpha[(scanline / 8) * 64 + 48]; + int i; + + if (scanline == 0) logerror("-------\n"); + + /* keep in range */ + if (base >= &atarigen_alpha[0x800]) + return; + + /* update the playfield scrolls */ + for (i = 0; i < 8; i++) + { + UINT16 word; + + word = *base++; + if (word & 0x8000) + { + int newscroll = (word >> 5) & 0x3ff; + int newbank = word & 0x1f; + if (newscroll != playfield_xscroll) + { + video_screen_update_partial(0, scanline + i - 1); + tilemap_set_scrollx(atarigen_playfield_tilemap, 0, newscroll); + playfield_xscroll = newscroll; + } + if (newbank != playfield_color_bank) + { + video_screen_update_partial(0, scanline + i - 1); + tilemap_mark_all_tiles_dirty(atarigen_playfield_tilemap); + playfield_color_bank = newbank; + } + } + + word = *base++; + if (word & 0x8000) + { + int newscroll = ((word >> 6) - (scanline + i)) & 0x1ff; + int newbank = word & 7; + if (newscroll != playfield_yscroll) + { + video_screen_update_partial(0, scanline + i - 1); + tilemap_set_scrolly(atarigen_playfield_tilemap, 0, newscroll); + playfield_yscroll = newscroll; + } + if (newbank != playfield_tile_bank) + { + video_screen_update_partial(0, scanline + i - 1); + tilemap_mark_all_tiles_dirty(atarigen_playfield_tilemap); + playfield_tile_bank = newbank; + } + } + } +} + + + +/************************************* + * + * Main refresh + * + *************************************/ + +VIDEO_UPDATE( atarig42 ) +{ + /* draw the playfield */ + fillbitmap(priority_bitmap, 0, cliprect); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 0, 0); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 1, 1); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 2, 2); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 3, 3); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 4, 4); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 5, 5); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 6, 6); + tilemap_draw(bitmap, cliprect, atarigen_playfield_tilemap, 7, 7); + + /* copy the motion objects on top */ + { + mame_bitmap *mo_bitmap = atarirle_get_vram(0, 0); + int left = cliprect->min_x; + int top = cliprect->min_y; + int right = cliprect->max_x + 1; + int bottom = cliprect->max_y + 1; + int x, y; + + /* now blend with the playfield */ + for (y = top; y < bottom; y++) + { + UINT16 *pf = (UINT16 *)bitmap->base + y * bitmap->rowpixels; + UINT16 *mo = (UINT16 *)mo_bitmap->base + y * mo_bitmap->rowpixels; + UINT8 *pri = (UINT8 *)priority_bitmap->base + priority_bitmap->rowpixels * y; + for (x = left; x < right; x++) + if (mo[x]) + { + int pfpri = pri[x]; + int mopri = mo[x] >> ATARIMO_PRIORITY_SHIFT; + if (mopri >= pfpri) + pf[x] = mo[x] & ATARIRLE_DATA_MASK; + } + } + } + + /* add the alpha on top */ + tilemap_draw(bitmap, cliprect, atarigen_alpha_tilemap, 0, 0); + return 0; +} |