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atarisy1.c
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C/C++ Source or Header
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2000-05-18
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/***************************************************************************
Atari System 1 hardware
****************************************************************************/
#include "driver.h"
#include "machine/atarigen.h"
#include "vidhrdw/generic.h"
#define XCHARS 42
#define YCHARS 30
#define XDIM (XCHARS*8)
#define YDIM (YCHARS*8)
/*************************************
*
* Constants
*
*************************************/
/* the color and remap PROMs are mapped as follows */
#define PROM1_BANK_4 0x80 /* active low */
#define PROM1_BANK_3 0x40 /* active low */
#define PROM1_BANK_2 0x20 /* active low */
#define PROM1_BANK_1 0x10 /* active low */
#define PROM1_OFFSET_MASK 0x0f /* postive logic */
#define PROM2_BANK_6_OR_7 0x80 /* active low */
#define PROM2_BANK_5 0x40 /* active low */
#define PROM2_PLANE_5_ENABLE 0x20 /* active high */
#define PROM2_PLANE_4_ENABLE 0x10 /* active high */
#define PROM2_PF_COLOR_MASK 0x0f /* negative logic */
#define PROM2_BANK_7 0x08 /* active low, plus PROM2_BANK_6_OR_7 low as well */
#define PROM2_MO_COLOR_MASK 0x07 /* negative logic */
#define OVERRENDER_PRIORITY 1
#define OVERRENDER_SPECIAL 2
/*************************************
*
* Macros
*
*************************************/
/* these macros make accessing the indirection table easier, plus this is how the data
is stored for the pfmapped array */
#define PACK_LOOKUP_DATA(bank,color,offset,bpp) \
(((((bpp) - 4) & 7) << 24) | \
(((color) & 255) << 16) | \
(((bank) & 15) << 12) | \
(((offset) & 15) << 8))
#define LOOKUP_BPP(data) (((data) >> 24) & 7)
#define LOOKUP_COLOR(data) (((data) >> 16) & 0xff)
#define LOOKUP_GFX(data) (((data) >> 12) & 15)
#define LOOKUP_CODE(data) ((data) & 0x0fff)
/*************************************
*
* Structures
*
*************************************/
struct pf_overrender_data
{
struct osd_bitmap *bitmap;
int type;
};
/*************************************
*
* Globals we own
*
*************************************/
UINT8 *atarisys1_bankselect;
UINT8 *atarisys1_prioritycolor;
/*************************************
*
* Statics
*
*************************************/
/* playfield parameters */
static struct atarigen_pf_state pf_state;
static UINT16 priority_pens;
/* indirection tables */
static UINT32 pf_lookup[256];
static UINT32 mo_lookup[256];
/* INT3 tracking */
static void *int3_timer[YDIM];
static void *int3off_timer;
/* graphics bank tracking */
static UINT8 bank_gfx[3][8];
static unsigned int *pen_usage[MAX_GFX_ELEMENTS];
/* basic form of a graphics bank */
static struct GfxLayout objlayout =
{
8,8, /* 8*8 sprites */
4096, /* 4096 of them */
6, /* 6 bits per pixel */
{ 5*8*0x08000, 4*8*0x08000, 3*8*0x08000, 2*8*0x08000, 1*8*0x08000, 0*8*0x08000 },
{ 0, 1, 2, 3, 4, 5, 6, 7 },
{ 0*8, 1*8, 2*8, 3*8, 4*8, 5*8, 6*8, 7*8 },
8*8 /* every sprite takes 8 consecutive bytes */
};
/*************************************
*
* Prototypes
*
*************************************/
static const UINT8 *update_palette(void);
static void pf_color_callback(const struct rectangle *clip, const struct rectangle *tiles, const struct atarigen_pf_state *state, void *data);
static void pf_render_callback(const struct rectangle *clip, const struct rectangle *tiles, const struct atarigen_pf_state *state, void *data);
static void pf_overrender_callback(const struct rectangle *clip, const struct rectangle *tiles, const struct atarigen_pf_state *state, void *data);
static void mo_color_callback(const UINT16 *data, const struct rectangle *clip, void *param);
static void mo_render_callback(const UINT16 *data, const struct rectangle *clip, void *param);
static int decode_gfx(void);
static int get_bank(UINT8 prom1, UINT8 prom2, int bpp);
void atarisys1_scanline_update(int scanline);
/*************************************
*
* Generic video system start
*
*************************************/
int atarisys1_vh_start(void)
{
static struct atarigen_mo_desc mo_desc =
{
64, /* maximum number of MO's */
2, /* number of bytes per MO entry */
0x80, /* number of bytes between MO words */
1, /* ignore an entry if this word == 0xffff */
3, 0, 0x3f, /* link = (data[linkword] >> linkshift) & linkmask */
0 /* render in reverse link order */
};
static struct atarigen_pf_desc pf_desc =
{
8, 8, /* width/height of each tile */
64, 64 /* number of tiles in each direction */
};
int i, e;
/* first decode the graphics */
if (decode_gfx())
return 1;
/* reset the statics */
memset(&pf_state, 0, sizeof(pf_state));
memset(int3_timer, 0, sizeof(int3_timer));
/* initialize the pen usage array */
for (e = 0; e < MAX_GFX_ELEMENTS; e++)
if (Machine->gfx[e])
{
pen_usage[e] = Machine->gfx[e]->pen_usage;
/* if this element has 6bpp data, create a special new usage array for it */
if (Machine->gfx[e]->color_granularity == 64)
{
const struct GfxElement *gfx = Machine->gfx[e];
/* allocate storage */
pen_usage[e] = malloc(gfx->total_elements * 2 * sizeof(int));
if (pen_usage[e])
{
unsigned int *entry;
int x, y;
/* scan each entry, marking which pens are used */
memset(pen_usage[e], 0, gfx->total_elements * 2 * sizeof(int));
for (i = 0, entry = pen_usage[e]; i < gfx->total_elements; i++, entry += 2)
{
UINT8 *dp = gfx->gfxdata + i * gfx->char_modulo;
for (y = 0; y < gfx->height; y++)
{
for (x = 0; x < gfx->width; x++)
{
int color = dp[x];
entry[(color >> 5) & 1] |= 1 << (color & 31);
}
dp += gfx->line_modulo;
}
}
}
}
}
/* initialize the playfield */
if (atarigen_pf_init(&pf_desc))
return 1;
/* initialize the motion objects */
if (atarigen_mo_init(&mo_desc))
{
atarigen_pf_free();
return 1;
}
return 0;
}
/*************************************
*
* Video system shutdown
*
*************************************/
void atarisys1_vh_stop(void)
{
int i;
/* free any extra pen usage */
for (i = 0; i < MAX_GFX_ELEMENTS; i++)
{
if (pen_usage[i] && Machine->gfx[i] && pen_usage[i] != Machine->gfx[i]->pen_usage)
free(pen_usage[i]);
pen_usage[i] = 0;
}
atarigen_pf_free();
atarigen_mo_free();
}
/*************************************
*
* Graphics bank selection
*
*************************************/
WRITE_HANDLER( atarisys1_bankselect_w )
{
int oldword = READ_WORD(&atarisys1_bankselect[offset]);
int newword = COMBINE_WORD(oldword, data);
int scanline = cpu_getscanline();
int diff = oldword ^ newword;
/* update memory */
WRITE_WORD(&atarisys1_bankselect[offset], newword);
/* sound CPU reset */
if (diff & 0x0080)
{
cpu_set_reset_line(1, (newword & 0x0080) ? CLEAR_LINE : ASSERT_LINE);
if (!(newword & 0x0080)) atarigen_sound_reset();
}
/* motion object bank select */
atarisys1_scanline_update(scanline);
/* playfield bank select */
if (diff & 0x04)
{
pf_state.param[0] = (newword & 0x04) ? 0x80 : 0x00;
atarigen_pf_update(&pf_state, cpu_getscanline() + 1);
}
}
/*************************************
*
* Playfield horizontal scroll
*
*************************************/
WRITE_HANDLER( atarisys1_hscroll_w )
{
int oldword = READ_WORD(&atarigen_hscroll[offset]);
int newword = COMBINE_WORD(oldword, data);
WRITE_WORD(&atarigen_hscroll[offset], newword);
/* set the new scroll value and update the playfield status */
pf_state.hscroll = newword & 0x1ff;
atarigen_pf_update(&pf_state, cpu_getscanline() + 1);
}
/*************************************
*
* Playfield vertical scroll
*
*************************************/
WRITE_HANDLER( atarisys1_vscroll_w )
{
int scanline = cpu_getscanline() + 1;
int oldword = READ_WORD(&atarigen_vscroll[offset]);
int newword = COMBINE_WORD(oldword, data);
WRITE_WORD(&atarigen_vscroll[offset], newword);
/* because this latches a new value into the scroll base,
we need to adjust for the scanline */
pf_state.vscroll = newword & 0x1ff;
if (scanline < YDIM) pf_state.vscroll -= scanline;
atarigen_pf_update(&pf_state, scanline);
}
/*************************************
*
* Playfield RAM write handler
*
*************************************/
WRITE_HANDLER( atarisys1_playfieldram_w )
{
int oldword = READ_WORD(&atarigen_playfieldram[offset]);
int newword = COMBINE_WORD(oldword, data);
if (oldword != newword)
{
WRITE_WORD(&atarigen_playfieldram[offset], newword);
atarigen_pf_dirty[offset / 2] = 0xff;
}
}
/*************************************
*
* Sprite RAM write handler
*
*************************************/
WRITE_HANDLER( atarisys1_spriteram_w )
{
int oldword = READ_WORD(&atarigen_spriteram[offset]);
int newword = COMBINE_WORD(oldword, data);
if (oldword != newword)
{
WRITE_WORD(&atarigen_spriteram[offset], newword);
/* if modifying a timer, beware */
if (((offset & 0x180) == 0x000 && READ_WORD(&atarigen_spriteram[offset | 0x080]) == 0xffff) ||
((offset & 0x180) == 0x080 && newword == 0xffff))
{
/* if the timer is in the active bank, update the display list */
if ((offset >> 9) == ((READ_WORD(&atarisys1_bankselect[0]) >> 3) & 7))
{
logerror("Caught timer mod!\n");
atarisys1_scanline_update(cpu_getscanline());
}
}
}
}
/*************************************
*
* MO interrupt handlers
*
*************************************/
static void int3off_callback(int param)
{
/* clear the state */
atarigen_scanline_int_ack_w(0, 0);
/* make this timer go away */
int3off_timer = 0;
}
void atarisys1_int3_callback(int param)
{
/* update the state */
atarigen_scanline_int_gen();
/* set a timer to turn it off */
if (int3off_timer)
timer_remove(int3off_timer);
int3off_timer = timer_set(cpu_getscanlineperiod(), 0, int3off_callback);
/* set ourselves up to go off next frame */
int3_timer[param] = timer_set(TIME_IN_HZ(Machine->drv->frames_per_second), param, atarisys1_int3_callback);
}
/*************************************
*
* MO interrupt state read
*
*************************************/
READ_HANDLER( atarisys1_int3state_r )
{
return atarigen_scanline_int_state ? 0x0080 : 0x0000;
}
/*************************************
*
* Periodic MO updater
*
*************************************/
void atarisys1_scanline_update(int scanline)
{
int bank = ((READ_WORD(&atarisys1_bankselect[0]) >> 3) & 7) * 0x200;
UINT8 *base = &atarigen_spriteram[bank];
UINT8 spritevisit[64];
UINT8 timer[YDIM];
int link = 0;
int i;
/* only process if we're still onscreen */
if (scanline < YDIM)
{
/* generic update first */
if (!scanline)
atarigen_mo_update(base, 0, 0);
else
atarigen_mo_update(base, 0, scanline + 1);
}
/* visit all the sprites and look for timers */
memset(spritevisit, 0, sizeof(spritevisit));
memset(timer, 0, sizeof(timer));
while (!spritevisit[link])
{
int data2 = READ_WORD(&base[link * 2 + 0x080]);
/* a codeure of 0xffff is really an interrupt - gross! */
if (data2 == 0xffff)
{
int data1 = READ_WORD(&base[link * 2 + 0x000]);
int vsize = (data1 & 15) + 1;
int ypos = (256 - (data1 >> 5) - vsize * 8) & 0x1ff;
/* only generate timers on visible scanlines */
if (ypos < YDIM)
timer[ypos] = 1;
}
/* link to the next object */
spritevisit[link] = 1;
link = READ_WORD(&atarigen_spriteram[bank + link * 2 + 0x180]) & 0x3f;
}
/* update our interrupt timers */
for (i = 0; i < YDIM; i++)
{
if (timer[i] && !int3_timer[i])
int3_timer[i] = timer_set(cpu_getscanlinetime(i), i, atarisys1_int3_callback);
else if (!timer[i] && int3_timer[i])
{
timer_remove(int3_timer[i]);
int3_timer[i] = 0;
}
}
}
/*************************************
*
* Main refresh
*
*************************************/
void atarisys1_vh_screenrefresh(struct osd_bitmap *bitmap,int full_refresh)
{
int i;
/* update the palette */
if (update_palette())
memset(atarigen_pf_dirty, 0xff, atarigen_playfieldram_size / 2);
/* set up the all-transparent overrender palette */
for (i = 0; i < 16; i++)
atarigen_overrender_colortable[i] = palette_transparent_pen;
/* render the playfield */
memset(atarigen_pf_visit, 0, 64*64);
atarigen_pf_process(pf_render_callback, bitmap, &Machine->drv->visible_area);
/* render the motion objects */
priority_pens = READ_WORD(&atarisys1_prioritycolor[0]) & 0xff;
atarigen_mo_process(mo_render_callback, bitmap);
/* redraw the alpha layer completely */
{
const struct GfxElement *gfx = Machine->gfx[0];
int sx, sy, offs;
for (sy = 0; sy < YCHARS; sy++)
for (sx = 0, offs = sy*64; sx < XCHARS; sx++, offs++)
{
int data = READ_WORD(&atarigen_alpharam[offs * 2]);
int opaque = data & 0x2000;
int code = data & 0x3ff;
if (code || opaque)
{
int color = (data >> 10) & 7;
drawgfx(bitmap, gfx, code, color, 0, 0, 8 * sx, 8 * sy, 0,
opaque ? TRANSPARENCY_NONE : TRANSPARENCY_PEN, 0);
}
}
}
/* update onscreen messages */
atarigen_update_messages();
}
/*************************************
*
* Palette management
*
*************************************/
static const UINT8 *update_palette(void)
{
UINT16 al_map[8], pfmo_map[32];
int i, j;
/* reset color tracking */
memset(pfmo_map, 0, sizeof(pfmo_map));
memset(al_map, 0, sizeof(al_map));
palette_init_used_colors();
/* always remap the transluscent colors */
memset(&palette_used_colors[0x300], PALETTE_COLOR_USED, 16);
/* update color usage for the playfield */
atarigen_pf_process(pf_color_callback, pfmo_map, &Machine->drv->visible_area);
/* update color usage for the mo's */
atarigen_mo_process(mo_color_callback, pfmo_map);
/* update color usage for the alphanumerics */
{
const unsigned int *usage = Machine->gfx[0]->pen_usage;
int sx, sy, offs;
for (sy = 0; sy < YCHARS; sy++)
for (sx = 0, offs = sy * 64; sx < XCHARS; sx++, offs++)
{
int data = READ_WORD(&atarigen_alpharam[offs * 2]);
int color = (data >> 10) & 7;
int code = data & 0x3ff;
al_map[color] |= usage[code];
}
}
/* determine the final playfield palette */
for (i = 16; i < 32; i++)
{
UINT16 used = pfmo_map[i];
if (used)
for (j = 0; j < 16; j++)
if (used & (1 << j))
palette_used_colors[0x100 + i * 16 + j] = PALETTE_COLOR_USED;
}
/* determine the final motion object palette */
for (i = 0; i < 16; i++)
{
UINT16 used = pfmo_map[i];
if (used)
{
palette_used_colors[0x100 + i * 16] = PALETTE_COLOR_TRANSPARENT;
for (j = 1; j < 16; j++)
if (used & (1 << j))
palette_used_colors[0x100 + i * 16 + j] = PALETTE_COLOR_USED;
}
}
/* determine the final alpha palette */
for (i = 0; i < 8; i++)
{
UINT16 used = al_map[i];
if (used)
for (j = 0; j < 4; j++)
if (used & (1 << j))
palette_used_colors[0x000 + i * 4 + j] = PALETTE_COLOR_USED;
}
/* recalculate the palette */
return palette_recalc();
}
/*************************************
*
* Playfield palette
*
*************************************/
static void pf_color_callback(const struct rectangle *clip, const struct rectangle *tiles, const struct atarigen_pf_state *state, void *param)
{
const UINT32 *lookup_table = &pf_lookup[state->param[0]];
UINT16 *colormap = param;
int x, y;
/* standard loop over tiles */
for (y = tiles->min_y; y != tiles->max_y; y = (y + 1) & 63)
for (x = tiles->min_x; x != tiles->max_x; x = (x + 1) & 63)
{
int offs = y * 64 + x;
int data = READ_WORD(&atarigen_playfieldram[offs * 2]);
int lookup = lookup_table[(data >> 8) & 0x7f];
const unsigned int *usage = pen_usage[LOOKUP_GFX(lookup)];
int bpp = LOOKUP_BPP(lookup);
int code = LOOKUP_CODE(lookup) | (data & 0xff);
int color = LOOKUP_COLOR(lookup);
unsigned int bits;
/* based on the depth, we need to tweak our pen mapping */
if (bpp == 0)
colormap[color] |= usage[code];
else if (bpp == 1)
{
bits = usage[code];
colormap[color * 2] |= bits;
colormap[color * 2 + 1] |= bits >> 16;
}
else
{
bits = usage[code * 2];
colormap[color * 4] |= bits;
colormap[color * 4 + 1] |= bits >> 16;
bits = usage[code * 2 + 1];
colormap[color * 4 + 2] |= bits;
colormap[color * 4 + 3] |= bits >> 16;
}
/* also mark unvisited tiles dirty */
if (!atarigen_pf_visit[offs]) atarigen_pf_dirty[offs] = 0xff;
}
}
/*************************************
*
* Playfield rendering
*
*************************************/
static void pf_render_callback(const struct rectangle *clip, const struct rectangle *tiles, const struct atarigen_pf_state *state, void *param)
{
int bank = state->param[0];
const UINT32 *lookup_table = &pf_lookup[bank];
struct osd_bitmap *bitmap = param;
int x, y;
/* standard loop over tiles */
for (y = tiles->min_y; y != tiles->max_y; y = (y + 1) & 63)
for (x = tiles->min_x; x != tiles->max_x; x = (x + 1) & 63)
{
int offs = y * 64 + x;
/* update only if dirty */
if (atarigen_pf_dirty[offs] != bank)
{
int data = READ_WORD(&atarigen_playfieldram[offs * 2]);
int lookup = lookup_table[(data >> 8) & 0x7f];
const struct GfxElement *gfx = Machine->gfx[LOOKUP_GFX(lookup)];
int code = LOOKUP_CODE(lookup) | (data & 0xff);
int color = LOOKUP_COLOR(lookup);
int hflip = data & 0x8000;
drawgfx(atarigen_pf_bitmap, gfx, code, color, hflip, 0, 8 * x, 8 * y, 0, TRANSPARENCY_NONE, 0);
atarigen_pf_dirty[offs] = bank;
}
/* track the tiles we've visited */
atarigen_pf_visit[offs] = 1;
}
/* then blast the result */
x = -state->hscroll;
y = -state->vscroll;
copyscrollbitmap(bitmap, atarigen_pf_bitmap, 1, &x, 1, &y, clip, TRANSPARENCY_NONE, 0);
}
/*************************************
*
* Playfield overrendering
*
*************************************/
static void pf_overrender_callback(const struct rectangle *clip, const struct rectangle *tiles, const struct atarigen_pf_state *state, void *param)
{
const UINT32 *lookup_table = &pf_lookup[state->param[0]];
const struct pf_overrender_data *overrender_data = param;
struct osd_bitmap *bitmap = overrender_data->bitmap;
int type = overrender_data->type;
int x, y;
/* standard loop over tiles */
for (y = tiles->min_y; y != tiles->max_y; y = (y + 1) & 63)
{
int sy = (8 * y - state->vscroll) & 0x1ff;
if (sy >= YDIM) sy -= 0x200;
for (x = tiles->min_x; x != tiles->max_x; x = (x + 1) & 63)
{
int offs = y * 64 + x;
int data = READ_WORD(&atarigen_playfieldram[offs * 2]);
int lookup = lookup_table[(data >> 8) & 0x7f];
const struct GfxElement *gfx = Machine->gfx[LOOKUP_GFX(lookup)];
int code = LOOKUP_CODE(lookup) | (data & 0xff);
int color = LOOKUP_COLOR(lookup);
int hflip = data & 0x8000;
int sx = (8 * x - state->hscroll) & 0x1ff;
if (sx >= XDIM) sx -= 0x200;
/* overrender based on the type */
if (type == OVERRENDER_PRIORITY)
{
int bpp = LOOKUP_BPP(lookup);
if (color == (16 >> bpp))
drawgfx(bitmap, gfx, code, color, hflip, 0, sx, sy, clip, TRANSPARENCY_PENS, ~priority_pens);
}
else
drawgfx(bitmap, gfx, code, color, hflip, 0, sx, sy, clip, TRANSPARENCY_PEN, 0);
}
}
}
/*************************************
*
* Motion object palette
*
*************************************/
static void mo_color_callback(const UINT16 *data, const struct rectangle *clip, void *param)
{
UINT16 *colormap = param;
UINT16 temp = 0;
int i;
UINT32 lookup = mo_lookup[data[1] >> 8];
const unsigned int *usage = pen_usage[LOOKUP_GFX(lookup)];
int code = LOOKUP_CODE(lookup) | (data[1] & 0xff);
int color = LOOKUP_COLOR(lookup);
int vsize = (data[0] & 0x000f) + 1;
int bpp = LOOKUP_BPP(lookup);
if (bpp == 0)
{
for (i = 0; i < vsize; i++)
temp |= usage[code++];
colormap[color] |= temp;
}
/* in theory we should support all 3 possible depths, but motion objects are all 4bpp */
}
/*************************************
*
* Motion object rendering
*
*************************************/
static void mo_render_callback(const UINT16 *data, const struct rectangle *clip, void *param)
{
struct osd_bitmap *bitmap = param;
struct pf_overrender_data overrender_data;
struct rectangle pf_clip;
/* extract data from the various words */
UINT32 lookup = mo_lookup[data[1] >> 8];
struct GfxElement *gfx = Machine->gfx[LOOKUP_GFX(lookup)];
int code = LOOKUP_CODE(lookup) | (data[1] & 0xff);
int color = LOOKUP_COLOR(lookup);
int xpos = data[2] >> 5;
int ypos = 256 - (data[0] >> 5);
int hflip = data[0] & 0x8000;
int vsize = (data[0] & 0x000f) + 1;
int priority = data[2] >> 15;
/* adjust for height */
ypos -= vsize * 8;
/* adjust the final coordinates */
xpos &= 0x1ff;
ypos &= 0x1ff;
if (xpos >= XDIM) xpos -= 0x200;
if (ypos >= YDIM) ypos -= 0x200;
/* bail if X coordinate is out of range */
if (xpos <= -8 || xpos >= XDIM)
return;
/* determine the bounding box */
atarigen_mo_compute_clip_8x8(pf_clip, xpos, ypos, 1, vsize, clip);
/* standard priority case? */
if (!priority)
{
/* draw the motion object */
atarigen_mo_draw_8x8_strip(bitmap, gfx, code, color, hflip, 0, xpos, ypos, vsize, clip, TRANSPARENCY_PEN, 0);
/* do we have a priority color active? */
if (priority_pens)
{
overrender_data.bitmap = bitmap;
overrender_data.type = OVERRENDER_PRIORITY;
/* overrender the playfield */
atarigen_pf_process(pf_overrender_callback, &overrender_data, &pf_clip);
}
}
/* high priority case? */
else
{
/* draw the sprite in bright pink on the real bitmap */
atarigen_mo_draw_transparent_8x8_strip(bitmap, gfx, code, hflip, 0, xpos, ypos, vsize, clip, TRANSPARENCY_PEN, 0);
/* also draw the sprite normally on the temp bitmap */
atarigen_mo_draw_8x8_strip(atarigen_pf_overrender_bitmap, gfx, code, 0x20, hflip, 0, xpos, ypos, vsize, clip, TRANSPARENCY_NONE, 0);
/* now redraw the playfield tiles over top of the sprite */
overrender_data.bitmap = atarigen_pf_overrender_bitmap;
overrender_data.type = OVERRENDER_SPECIAL;
atarigen_pf_process(pf_overrender_callback, &overrender_data, &pf_clip);
/* finally, copy this chunk to the real bitmap */
copybitmap(bitmap, atarigen_pf_overrender_bitmap, 0, 0, 0, 0, &pf_clip, TRANSPARENCY_THROUGH, palette_transparent_pen);
}
}
/*************************************
*
* Graphics decoding
*
*************************************/
static int decode_gfx(void)
{
UINT8 *prom1 = &memory_region(REGION_PROMS)[0x000];
UINT8 *prom2 = &memory_region(REGION_PROMS)[0x200];
int obj, i;
/* reset the globals */
memset(&bank_gfx, 0, sizeof(bank_gfx));
/* loop for two sets of objects */
for (obj = 0; obj < 2; obj++)
{
UINT32 *table = (obj == 0) ? pf_lookup : mo_lookup;
/* loop for 256 objects in the set */
for (i = 0; i < 256; i++, prom1++, prom2++)
{
int bank, bpp, color, offset;
/* determine the bpp */
bpp = 4;
if (*prom2 & PROM2_PLANE_4_ENABLE)
{
bpp = 5;
if (*prom2 & PROM2_PLANE_5_ENABLE)
bpp = 6;
}
/* determine the color */
if (obj == 0)
color = (16 + (~*prom2 & PROM2_PF_COLOR_MASK)) >> (bpp - 4); /* playfield */
else
color = (~*prom2 & PROM2_MO_COLOR_MASK) >> (bpp - 4); /* motion objects (high bit ignored) */
/* determine the offset */
offset = *prom1 & PROM1_OFFSET_MASK;
/* determine the bank */
bank = get_bank(*prom1, *prom2, bpp);
if (bank < 0)
return 1;
/* set the value */
if (bank == 0)
*table++ = 0;
else
*table++ = PACK_LOOKUP_DATA(bank, color, offset, bpp);
}
}
return 0;
}
/*************************************
*
* Graphics bank mapping
*
*************************************/
static int get_bank(UINT8 prom1, UINT8 prom2, int bpp)
{
int bank_offset[8] = { 0, 0x00000, 0x30000, 0x60000, 0x90000, 0xc0000, 0xe0000, 0x100000 };
int bank_index, i, gfx_index;
/* determine the bank index */
if ((prom1 & PROM1_BANK_1) == 0)
bank_index = 1;
else if ((prom1 & PROM1_BANK_2) == 0)
bank_index = 2;
else if ((prom1 & PROM1_BANK_3) == 0)
bank_index = 3;
else if ((prom1 & PROM1_BANK_4) == 0)
bank_index = 4;
else if ((prom2 & PROM2_BANK_5) == 0)
bank_index = 5;
else if ((prom2 & PROM2_BANK_6_OR_7) == 0)
{
if ((prom2 & PROM2_BANK_7) == 0)
bank_index = 7;
else
bank_index = 6;
}
else
return 0;
/* find the bank */
if (bank_gfx[bpp - 4][bank_index])
return bank_gfx[bpp - 4][bank_index];
/* if the bank is out of range, call it 0 */
if (bank_offset[bank_index] >= memory_region_length(REGION_GFX2))
return 0;
/* don't have one? let's make it ... first find any empty slot */
for (gfx_index = 0; gfx_index < MAX_GFX_ELEMENTS; gfx_index++)
if (Machine->gfx[gfx_index] == NULL)
break;
if (gfx_index == MAX_GFX_ELEMENTS)
return -1;
/* tweak the structure for the number of bitplanes we have */
objlayout.planes = bpp;
for (i = 0; i < bpp; i++)
objlayout.planeoffset[i] = (bpp - i - 1) * 0x8000 * 8;
/* decode the graphics */
Machine->gfx[gfx_index] = decodegfx(&memory_region(REGION_GFX2)[bank_offset[bank_index]], &objlayout);
if (!Machine->gfx[gfx_index])
return -1;
/* set the color information */
Machine->gfx[gfx_index]->colortable = &Machine->remapped_colortable[256];
Machine->gfx[gfx_index]->total_colors = 48 >> (bpp - 4);
/* set the entry and return it */
return bank_gfx[bpp - 4][bank_index] = gfx_index;
}