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-rw-r--r--src/mame/video/turbo.c1094
1 files changed, 1094 insertions, 0 deletions
diff --git a/src/mame/video/turbo.c b/src/mame/video/turbo.c
new file mode 100644
index 00000000000..e4b9258af8e
--- /dev/null
+++ b/src/mame/video/turbo.c
@@ -0,0 +1,1094 @@
+/*************************************************************************
+
+ Sega Z80-3D system
+
+*************************************************************************/
+
+#include "driver.h"
+#include "turbo.h"
+#include "video/resnet.h"
+#include <math.h>
+
+
+
+typedef struct _sprite_info sprite_info;
+struct _sprite_info
+{
+ UINT16 ve; /* VE0-15 signals for this row */
+ UINT8 lst; /* LST0-7 signals for this row */
+ UINT32 latched[8]; /* latched pixel data */
+ UINT8 plb[8]; /* latched PLB state */
+ UINT32 offset[8]; /* current offset for this row */
+ UINT32 frac[8]; /* leftover fraction */
+ UINT32 step[8]; /* stepping value */
+};
+
+static const UINT32 sprite_expand[16] =
+{
+ 0x00000000, 0x00000001, 0x00000100, 0x00000101,
+ 0x00010000, 0x00010001, 0x00010100, 0x00010101,
+ 0x01000000, 0x01000001, 0x01000100, 0x01000101,
+ 0x01010000, 0x01010001, 0x01010100, 0x01010101
+};
+
+
+
+
+/*************************************
+ *
+ * Palette conversion
+ *
+ *************************************/
+
+PALETTE_INIT( turbo )
+{
+ static const int resistances[3] = { 1000, 470, 220 };
+ double rweights[3], gweights[3], bweights[2];
+ int i;
+
+ /* compute the color output resistor weights */
+ compute_resistor_weights(0, 255, -1.0,
+ 3, &resistances[0], rweights, 470, 0,
+ 3, &resistances[0], gweights, 470, 0,
+ 2, &resistances[1], bweights, 470, 0);
+
+ /* initialize the palette with these colors */
+ for (i = 0; i < 256; i++)
+ {
+ int bit0, bit1, bit2, r, g, b;
+
+ /* red component */
+ bit0 = (i >> 0) & 1;
+ bit1 = (i >> 1) & 1;
+ bit2 = (i >> 2) & 1;
+ r = combine_3_weights(rweights, bit0, bit1, bit2);
+
+ /* green component */
+ bit0 = (i >> 3) & 1;
+ bit1 = (i >> 4) & 1;
+ bit2 = (i >> 5) & 1;
+ g = combine_3_weights(gweights, bit0, bit1, bit2);
+
+ /* blue component */
+ bit0 = (i >> 6) & 1;
+ bit1 = (i >> 7) & 1;
+ b = combine_2_weights(bweights, bit0, bit1);
+
+ palette_set_color(machine, i, MAKE_RGB(r, g, b));
+ }
+}
+
+
+PALETTE_INIT( subroc3d )
+{
+ static const int resistances[3] = { 1000, 470, 220 };
+ double rweights[3], gweights[3], bweights[2];
+ int i;
+
+ /* compute the color output resistor weights */
+ compute_resistor_weights(0, 255, -1.0,
+ 3, &resistances[0], rweights, 470, 0,
+ 3, &resistances[0], gweights, 470, 0,
+ 2, &resistances[1], bweights, 470, 0);
+
+ /* initialize the palette with these colors */
+ for (i = 0; i < 256; i++)
+ {
+ int bit0, bit1, bit2, r, g, b;
+
+ /* red component */
+ bit0 = (i >> 0) & 1;
+ bit1 = (i >> 1) & 1;
+ bit2 = (i >> 2) & 1;
+ r = combine_3_weights(rweights, bit0, bit1, bit2);
+
+ /* green component */
+ bit0 = (i >> 3) & 1;
+ bit1 = (i >> 4) & 1;
+ bit2 = (i >> 5) & 1;
+ g = combine_3_weights(gweights, bit0, bit1, bit2);
+
+ /* blue component */
+ bit0 = (i >> 6) & 1;
+ bit1 = (i >> 7) & 1;
+ b = combine_2_weights(bweights, bit0, bit1);
+
+ palette_set_color(machine, i, MAKE_RGB(r, g, b));
+ }
+}
+
+
+PALETTE_INIT( buckrog )
+{
+ static const int resistances[4] = { 2200, 1000, 500, 250 };
+ double rweights[3], gweights[3], bweights[4];
+ int i;
+
+ /* compute the color output resistor weights */
+ compute_resistor_weights(0, 255, -1.0,
+ 3, &resistances[1], rweights, 1000, 0,
+ 3, &resistances[1], gweights, 1000, 0,
+ 4, &resistances[0], bweights, 1000, 0);
+
+ /* initialize the palette with these colors */
+ for (i = 0; i < 1024; i++)
+ {
+ int bit0, bit1, bit2, bit3, r, g, b;
+
+ /* red component */
+ bit0 = (i >> 0) & 1;
+ bit1 = (i >> 1) & 1;
+ bit2 = (i >> 2) & 1;
+ r = combine_3_weights(rweights, bit0, bit1, bit2);
+
+ /* green component */
+ bit0 = (i >> 3) & 1;
+ bit1 = (i >> 4) & 1;
+ bit2 = (i >> 5) & 1;
+ g = combine_3_weights(gweights, bit0, bit1, bit2);
+
+ /* blue component - note the shuffled bits */
+ bit0 = (i >> 8) & 1;
+ bit1 = (i >> 9) & 1;
+ bit2 = (i >> 6) & 1;
+ bit3 = (i >> 7) & 1;
+ b = combine_4_weights(bweights, bit0, bit1, bit2, bit3);
+
+ palette_set_color(machine, i, MAKE_RGB(r, g, b));
+ }
+}
+
+
+
+/*************************************
+ *
+ * Video startup
+ *
+ *************************************/
+
+static TILE_GET_INFO( get_fg_tile_info )
+{
+ turbo_state *state = machine->driver_data;
+ int code = state->videoram[tile_index];
+ SET_TILE_INFO(0, code, code >> 2, 0);
+}
+
+
+VIDEO_START( turbo )
+{
+ turbo_state *state = machine->driver_data;
+
+ /* initialize the foreground tilemap */
+ state->fg_tilemap = tilemap_create(get_fg_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 8,8, 32,32);
+}
+
+
+VIDEO_START( buckrog )
+{
+ turbo_state *state = machine->driver_data;
+
+ /* initialize the foreground tilemap */
+ state->fg_tilemap = tilemap_create(get_fg_tile_info, tilemap_scan_rows, TILEMAP_TYPE_PEN, 8,8, 32,32);
+
+ /* allocate the bitmap RAM */
+ state->buckrog_bitmap_ram = auto_malloc(0xe000);
+ state_save_register_global_pointer(state->buckrog_bitmap_ram, 0xe000);
+}
+
+
+
+/*************************************
+ *
+ * Videoram access
+ *
+ *************************************/
+
+WRITE8_HANDLER( turbo_videoram_w )
+{
+ turbo_state *state = Machine->driver_data;
+ state->videoram[offset] = data;
+ if (offset < 0x400)
+ {
+ video_screen_update_partial(0, video_screen_get_vpos(0));
+ tilemap_mark_tile_dirty(state->fg_tilemap, offset);
+ }
+}
+
+
+WRITE8_HANDLER( buckrog_bitmap_w )
+{
+ turbo_state *state = Machine->driver_data;
+ state->buckrog_bitmap_ram[offset] = data & 1;
+}
+
+
+
+/*************************************
+ *
+ * Sprite X scaling
+ *
+ *************************************/
+
+INLINE UINT32 sprite_xscale(UINT8 dacinput, double vr1, double vr2, double cext)
+{
+ /* compute the effective pixel clock for this sprite */
+ /* thanks to Frank Palazzolo for figuring out this logic */
+
+ /* compute the control voltage to the VCO */
+ /* VR1 and VR2 are variable resistors on Turbo, fixed on other boards */
+ double iref = 5.0 / (1.5e3 + vr2);
+ double iout = iref * ((float)dacinput / 256.0);
+ double vref = 5.0 * 1e3 / (3.8e3 + 1e3 + vr1);
+ double vco_cv = (2.2e3 * iout) + vref;
+
+ /* based on the control voltage, compute the frequency assuming a 50pF */
+ /* external capacitor; this is the graph in the datasheet. Some attempt */
+ /* to simulate the non-linearity at the edges has been made, but it is */
+ /* admittedly cheesy. */
+ double vco_freq;
+ if (vco_cv > 5.0)
+ vco_cv = 5.0;
+ if (vco_cv < 0.0)
+ vco_cv = 0.0;
+ if (vco_cv < 1.33)
+ vco_freq = (0.68129 + pow(vco_cv + 0.6, 1.285)) * 1e6;
+ else if (vco_cv < 4.3)
+ vco_freq = (3 + (8 - 3) * ((vco_cv - 1.33) / (4.3 - 1.33))) * 1e6;
+ else
+ vco_freq = (-1.560279 + pow(vco_cv - 4.3 + 6, 1.26)) * 1e6;
+
+ /* now scale based on the actual external capacitor; the frequency goes */
+ /* up by a factor of 10 for every factor of 10 the capacitance is reduced */
+ /* approximately */
+ vco_freq *= 50e-12 / cext;
+
+ /* finally, convert to a fraction (8.24) of 5MHz, which is the pixel clock */
+ return (UINT32)((vco_freq / (5e6 * TURBO_X_SCALE)) * 16777216.0);
+}
+
+
+
+/*************************************
+ *
+ * Turbo sprite handling
+ *
+ *************************************/
+
+static void turbo_prepare_sprites(turbo_state *state, UINT8 y, sprite_info *info)
+{
+ const UINT8 *pr1119 = memory_region(REGION_PROMS) + 0x200;
+ int sprnum;
+
+ /* initialize the line enable signals to 0 */
+ info->ve = 0;
+ info->lst = 0;
+
+ /* compute the sprite information, which was done on the previous scanline during HBLANK */
+ for (sprnum = 0; sprnum < 16; sprnum++)
+ {
+ UINT8 *rambase = &state->spriteram[sprnum * 0x10];
+ int level = sprnum & 7;
+ UINT8 clo, chi;
+ UINT32 sum;
+
+ /* perform the first ALU to see if we are within the scanline */
+ sum = y + (rambase[0] ^ 0xff);
+ clo = (sum >> 8) & 1;
+ sum += (y << 8) + ((rambase[1] ^ 0xff) << 8);
+ chi = (sum >> 16) & 1;
+
+ /* the AND of the low carry and the inverse of the high carry clocks an enable bit */
+ /* for this sprite; note that the logic in the Turbo schematics is reversed here */
+ if (clo & (chi ^ 1))
+ {
+ int xscale = rambase[2] ^ 0xff;
+ int yscale = rambase[3];// ^ 0xff;
+ UINT16 offset = rambase[6] + (rambase[7] << 8);
+ int offs;
+
+ /* mark this entry enabled */
+ info->ve |= 1 << sprnum;
+
+ /* look up the low byte of the sum plus the yscale value in */
+ /* IC50/PR1119 to determine if we write back the sum of the */
+ /* offset and the rowbytes this scanline (p. 138) */
+ offs = (sum & 0xff) | /* A0-A7 = AL0-AL7 */
+ ((yscale & 0x08) << 5); /* A8-A9 = /RO11-/RO12 */
+
+ /* one of the bits is selected based on the low 7 bits of yscale */
+ if (!((pr1119[offs] >> (yscale & 0x07)) & 1))
+ {
+ offset += rambase[4] + (rambase[5] << 8);
+ rambase[6] = offset;
+ rambase[7] = offset >> 8;
+ }
+
+ /* the output of the ALU here goes to the individual level counter */
+ info->latched[level] = 0;
+ info->plb[level] = 0;
+ info->offset[level] = offset;
+ info->frac[level] = 0;
+
+ /*
+ actual pots read from one board:
+ VR1 = 310 Ohm
+ VR2 = 910 Ohm
+ */
+ info->step[level] = sprite_xscale(xscale, 1.0e3 * readinputportbytag("VR1") / 100.0, 1.0e3 * readinputportbytag("VR2") / 100.0, 100e-12);
+ }
+ }
+}
+
+
+static UINT32 turbo_get_sprite_bits(UINT8 road, sprite_info *sprinfo)
+{
+ const UINT8 *sprite_gfxdata = memory_region(REGION_GFX1);
+ UINT8 sprlive = sprinfo->lst;
+ UINT32 sprdata = 0;
+ int level;
+
+ /* if we haven't left the road yet, sprites 3-7 are disabled */
+ if (!road)
+ sprlive &= 0x07;
+
+ /* loop over all live levels */
+ for (level = 0; level < 8; level++)
+ if (sprlive & (1 << level))
+ {
+ /* latch the data and advance the offset */
+ sprdata |= sprinfo->latched[level];
+ sprinfo->frac[level] += sprinfo->step[level];
+
+ /* if we're live and we've clocked more data, advance */
+ while (sprinfo->frac[level] >= 0x1000000)
+ {
+ UINT16 offs = sprinfo->offset[level];
+ UINT8 pixdata;
+
+ /* bit 0 controls which half of the byte to use */
+ /* bits 1-13 go to address lines */
+ /* bit 14 selects which of the two ROMs to read from */
+ pixdata = sprite_gfxdata[(level << 14) | ((offs >> 1) & 0x3fff)] >> ((~offs & 1) * 4);
+ sprinfo->latched[level] = sprite_expand[pixdata & 0x0f] << level;
+
+ /* if bit 3 is 0 and bit 2 is 1, the enable flip/flip is reset */
+ if ((pixdata & 0x0c) == 0x04)
+ {
+ sprinfo->lst &= ~(1 << level);
+ sprlive &= ~(1 << level);
+ }
+
+ /* if bit 15 is set, we decrement instead of increment */
+ sprinfo->offset[level] += (offs & 0x8000) ? -1 : 1;
+ sprinfo->frac[level] -= 0x1000000;
+ }
+ }
+
+ return sprdata;
+}
+
+
+
+/*************************************
+ *
+ * Turbo video update
+ *
+ *************************************/
+
+VIDEO_UPDATE( turbo )
+{
+ turbo_state *state = machine->driver_data;
+ mame_bitmap *fgpixmap = tilemap_get_pixmap(state->fg_tilemap);
+ const UINT8 *road_gfxdata = memory_region(REGION_GFX3);
+ const UINT8 *prom_base = memory_region(REGION_PROMS);
+ const UINT8 *pr1114 = prom_base + 0x000;
+ const UINT8 *pr1115 = prom_base + 0x020;
+ const UINT8 *pr1116 = prom_base + 0x040;
+ const UINT8 *pr1117 = prom_base + 0x060;
+ const UINT8 *pr1118 = prom_base + 0x100;
+ const UINT8 *pr1121 = prom_base + 0x600;
+ const UINT8 *pr1122 = prom_base + 0x800;
+ const UINT8 *pr1123 = prom_base + 0xc00;
+ int x, y;
+
+ /* loop over rows */
+ for (y = cliprect->min_y; y <= cliprect->max_y; y++)
+ {
+ const UINT16 *fore = (UINT16 *)fgpixmap->base + y * fgpixmap->rowpixels;
+ UINT16 *dest = (UINT16 *)bitmap->base + y * bitmap->rowpixels;
+ int sel, coch, babit, slipar_acciar, area, offs, areatmp, road = 0;
+ sprite_info sprinfo;
+
+ /* compute the Y sum between opa and the current scanline (p. 141) */
+ int va = (y + state->turbo_opa) & 0xff;
+
+ /* the upper bit of OPC inverts the road (p. 141) */
+ if (!(state->turbo_opc & 0x80))
+ va ^= 0xff;
+
+ /* compute the sprite information; we use y-1 since this info was computed during HBLANK */
+ /* on the previous scanline */
+ turbo_prepare_sprites(state, y, &sprinfo);
+
+ /* loop over columns */
+ for (x = 0; x <= cliprect->max_x; x += TURBO_X_SCALE)
+ {
+ int bacol, red, grn, blu, priority, foreraw, forebits, mx, ix;
+ int xx = x / TURBO_X_SCALE;
+ UINT8 carry;
+ UINT32 sprbits;
+ UINT16 he;
+
+ /* load the bitmask from the sprite position for both halves of the sprites (p. 139) */
+ he = state->sprite_position[xx] | (state->sprite_position[xx + 0x100] << 8);
+
+ /* the AND of the line enable and horizontal enable is clocked and held in LST0-7 (p. 143) */
+ he &= sprinfo.ve;
+ sprinfo.lst |= he | (he >> 8);
+
+ /* compute the X sum between opb and the current column; only the carry matters (p. 141) */
+ carry = (xx + state->turbo_opb) >> 8;
+
+ /* the carry selects which inputs to use (p. 141) */
+ if (carry)
+ {
+ sel = state->turbo_ipb;
+ coch = state->turbo_ipc >> 4;
+ }
+ else
+ {
+ sel = state->turbo_ipa;
+ coch = state->turbo_ipc & 15;
+ }
+
+ /* look up AREA1 and AREA2 (p. 142) */
+ offs = va | /* A0- A7 = VA0-VA7 */
+ ((sel & 0x0f) << 8); /* A8-A11 = SEL0-3 */
+
+ areatmp = road_gfxdata[0x0000 | offs];
+ areatmp = ((areatmp + xx) >> 8) & 0x01;
+ area = areatmp << 0;
+
+ areatmp = road_gfxdata[0x1000 | offs];
+ areatmp = ((areatmp + xx) >> 8) & 0x01;
+ area |= areatmp << 1;
+
+ /* look up AREA3 and AREA4 (p. 142) */
+ offs = va | /* A0- A7 = VA0-VA7 */
+ ((sel & 0xf0) << 4); /* A8-A11 = SEL4-7 */
+
+ areatmp = road_gfxdata[0x2000 | offs];
+ areatmp = ((areatmp + xx) >> 8) & 0x01;
+ area |= areatmp << 2;
+
+ areatmp = road_gfxdata[0x3000 | offs];
+ areatmp = ((areatmp + xx) >> 8) & 0x01;
+ area |= areatmp << 3;
+
+ /* look up AREA5 (p. 141) */
+ offs = (xx >> 3) | /* A0- A4 = H3-H7 */
+ ((state->turbo_opc & 0x3f) << 5); /* A5-A10 = OPC0-5 */
+
+ areatmp = road_gfxdata[0x4000 | offs];
+ areatmp = (areatmp << (xx & 7)) & 0x80;
+ area |= areatmp >> 3;
+
+ /* compute the final area value and look it up in IC18/PR1115 (p. 144) */
+ /* note: SLIPAR is 0 on the road surface only */
+ /* ACCIAR is 0 on the road surface and the striped edges only */
+ babit = pr1115[area];
+ slipar_acciar = babit & 0x30;
+ if (!road && (slipar_acciar & 0x20))
+ road = 1;
+
+ /* also use the coch value to look up color info in IC13/PR1114 and IC21/PR1117 (p. 144) */
+ offs = (coch & 0x0f) | /* A0-A3: CONT0-3 = COCH0-3 */
+ ((state->turbo_fbcol & 0x01) << 4); /* A4: COL0 */
+ bacol = pr1114[offs] | (pr1117[offs] << 8);
+
+ /* at this point, do the character lookup; due to the shift register loading in */
+ /* the sync PROM, we latch character 0 during pixel 6 and start clocking in pixel */
+ /* 8, effectively shifting the display by 8; at pixel 0x108, the color latch is */
+ /* forced clear and isn't touched until the next shift register load */
+ foreraw = (xx < 8 || xx >= 0x108) ? 0 : fore[xx - 8];
+
+ /* perform the foreground color table lookup in IC99/PR1118 (p. 137) */
+ forebits = pr1118[foreraw];
+
+ /* now that we have done all the per-5MHz pixel work, mix the sprites at the scale factor */
+ for (ix = 0; ix < TURBO_X_SCALE; ix++)
+ {
+ /* iterate over live sprites and update them */
+ /* the final 32-bit value is: */
+ /* CDB0-7 = D0 -D7 */
+ /* CDG0-7 = D8 -D15 */
+ /* CDR0-7 = D16-D23 */
+ /* PLB0-7 = D24-D31 */
+ sprbits = turbo_get_sprite_bits(road, &sprinfo);
+
+ /* perform collision detection here via lookup in IC20/PR1116 (p. 144) */
+ state->turbo_collision |= pr1116[((sprbits >> 24) & 7) | (slipar_acciar >> 1)];
+
+ /* look up the sprite priority in IC11/PR1122 (p. 144) */
+ priority = ((sprbits & 0xfe000000) >> 25) | /* A0-A6: PLB1-7 */
+ ((state->turbo_fbpla & 0x07) << 7); /* A7-A9: PLA0-2 */
+ priority = pr1122[priority];
+
+ /* use that to look up the overall priority in IC12/PR1123 (p. 144) */
+ mx = (priority & 7) | /* A0-A2: PR-1122 output, bits 0-2 */
+ ((sprbits & 0x01000000) >> 21) | /* A3: PLB0 */
+ ((foreraw & 0x80) >> 3) | /* A4: PLBE */
+ ((forebits & 0x08) << 2) | /* A5: PLBF */
+ ((babit & 0x07) << 6) | /* A6-A8: BABIT1-3 */
+ ((state->turbo_fbpla & 0x08) << 6); /* A9: PLA3 */
+ mx = pr1123[mx];
+
+ /* the MX output selects one of 16 inputs; build up a 16-bit pattern to match */
+ /* these in red, green, and blue (p. 144) */
+ red = ((sprbits & 0x0000ff) >> 0) | /* D0- D7: CDR0-CDR7 */
+ ((forebits & 0x01) << 8) | /* D8: CDRF */
+ ((bacol & 0x001f) << 9) | /* D9-D13: BAR0-BAR4 */
+ (1 << 14) | /* D14: 1 */
+ (0 << 15); /* D15: 0 */
+
+ grn = ((sprbits & 0x00ff00) >> 8) | /* D0- D7: CDG0-CDG7 */
+ ((forebits & 0x02) << 7) | /* D8: CDGF */
+ ((bacol & 0x03e0) << 4) | /* D9-D13: BAG0-BAG4 */
+ (1 << 14) | /* D14: 1 */
+ (0 << 15); /* D15: 0 */
+
+ blu = ((sprbits & 0xff0000) >> 16) | /* D0- D7: CDB0-CDB7 */
+ ((forebits & 0x04) << 6) | /* D8: CDBF */
+ ((bacol & 0x7c00) >> 1) | /* D9-D13: BAB0-BAB4 */
+ (1 << 14) | /* D14: 1 */
+ (0 << 15); /* D15: 0 */
+
+ /* we then go through a muxer to select one of the 16 outputs computed above (p. 144) */
+ offs = mx | /* A0-A3: MX0-MX3 */
+ (((~red >> mx) & 1) << 4) | /* A4: CDR */
+ (((~grn >> mx) & 1) << 5) | /* A5: CDG */
+ (((~blu >> mx) & 1) << 6) | /* A6: CDB */
+ ((state->turbo_fbcol & 6) << 6); /* A7-A8: COL1-2 */
+ dest[x + ix] = pr1121[offs];
+ }
+ }
+ }
+ return 0;
+}
+
+
+
+/*************************************
+ *
+ * Subroc 3D sprite handling
+ *
+ *************************************/
+
+/*
+ Sprite state machine:
+
+ 1LINE = 0 (V & 0x108 == 0x108)
+ ---------
+ 0 1 2 3 4 5 6 7 8 9 A B C D E F
+ 20 21 21 20 20 21 21 20 20 05 25 2c 07 e7 37 22
+ _____ _____ _____ ________
+ RAD0 = ___| |_____| |_____| |__| |___
+ ___________
+ RAD7 = ____________________________________| |
+ _________________
+ YCULL= ___________________________| |___
+ __
+ AX = _________________________________| |____________
+ __
+ D/A = __________________________________________| |___
+ ___________________________ _____ _________
+ /CLK1= |__| |__|
+ __
+ WRPL = _______________________________________| |______
+ __
+ /CLK2= _______________________________________| |______
+
+
+
+ 1LINE = 1 (V & 0x108 != 0x108)
+ ---------
+ 0 1 2 3 4 5 6 7 8 9 A B C D E F
+ 2c 2c 2c 2f 2f 2f 2f 20 2d 2d 2d 2d 0f 6f 2f 20
+ ___________ ____________________
+ RAD0 = _________| |__| |___
+ ___________ ________
+ RAD7 = _________| |______________| |___
+ _____________________ ____________________
+ YCULL= |__| |___
+ _____________________ ____________________
+ AX = |__| |___
+
+ D/A = _________________________________________________
+ ____________________________________ _________
+ /CLK1= |__|
+ __
+ WRPL = _______________________________________| |______
+
+ /CLK2= _________________________________________________
+
+*/
+
+static void subroc3d_prepare_sprites(turbo_state *state, UINT8 y, sprite_info *info)
+{
+ const UINT8 *pr1449 = memory_region(REGION_PROMS) + 0x300;
+ int sprnum;
+
+ /* initialize the line enable signals to 0 */
+ info->ve = 0;
+ info->lst = 0;
+
+ /* compute the sprite information, which was done on the previous scanline during HBLANK */
+ for (sprnum = 0; sprnum < 16; sprnum++)
+ {
+ UINT8 *rambase = &state->spriteram[sprnum * 8];
+ int level = sprnum & 7;
+ UINT8 clo, chi;
+ UINT32 sum;
+
+ /* perform the first ALU to see if we are within the scanline */
+ sum = y + (rambase[0]/* ^ 0xff*/);
+ clo = (sum >> 8) & 1;
+ sum += (y << 8) + ((rambase[1]/* ^ 0xff*/) << 8);
+ chi = (sum >> 16) & 1;
+
+ /* the AND of the low carry and the inverse of the high carry clocks an enable bit */
+ /* for this sprite; note that the logic in the Turbo schematics is reversed here */
+ if (clo & (chi ^ 1))
+ {
+ int xscale = rambase[2] ^ 0xff;
+ int yscale = rambase[3];// ^ 0xff;
+ UINT16 offset = rambase[6] + (rambase[7] << 8);
+ int offs;
+
+ /* mark this entry enabled */
+ info->ve |= 1 << sprnum;
+
+ /* look up the low byte of the sum plus the yscale value in */
+ /* IC50/PR1119 to determine if we write back the sum of the */
+ /* offset and the rowbytes this scanline (p. 138) */
+ offs = (sum & 0xff) | /* A0-A7 = AL0-AL7 */
+ ((yscale & 0x08) << 5); /* A8-A9 = /RO11-/RO12 */
+
+ /* one of the bits is selected based on the low 7 bits of yscale */
+ if (!((pr1449[offs] >> (yscale & 0x07)) & 1))
+ {
+ offset += rambase[4] + (rambase[5] << 8);
+ rambase[6] = offset;
+ rambase[7] = offset >> 8;
+ }
+
+ /* the output of the ALU here goes to the individual level counter */
+ info->latched[level] = 0;
+ info->plb[level] = 0;
+ info->offset[level] = offset << 1;
+ info->frac[level] = 0;
+ info->step[level] = sprite_xscale(xscale, 1.2e3, 1.2e3, 220e-12);
+ }
+ }
+}
+
+
+static UINT32 subroc3d_get_sprite_bits(sprite_info *sprinfo, UINT8 *plb)
+{
+ /* see logic on each sprite:
+ END = (CDA == 1 && (CDA ^ CDB) == 0 && (CDC ^ CDD) == 0)
+ PLB = END ^ (CDA == 1 && (CDC ^ CDD) == 0)
+ end is in bit 1, plb in bit 0
+ */
+ static const UINT8 plb_end[16] = { 0,1,1,2, 1,1,1,1, 1,1,1,1, 0,1,1,2 };
+ const UINT8 *sprite_gfxdata = memory_region(REGION_GFX1);
+ UINT32 sprdata = 0;
+ int level;
+
+ *plb = 0;
+
+ /* loop over all live levels */
+ for (level = 0; level < 8; level++)
+ if (sprinfo->lst & (1 << level))
+ {
+ /* latch the data and advance the offset */
+ sprdata |= sprinfo->latched[level];
+ *plb |= sprinfo->plb[level];
+ sprinfo->frac[level] += sprinfo->step[level];
+
+ /* if we're live and we've clocked more data, advance */
+ while (sprinfo->frac[level] >= 0x800000)
+ {
+ UINT32 offs = sprinfo->offset[level];
+ UINT8 pixdata;
+
+ /* bit 0 controls which half of the byte to use */
+ /* bits 1-13 go to address lines */
+ /* bit 14 selects which of the two ROMs to read from */
+ pixdata = sprite_gfxdata[(level << 15) | ((offs >> 1) & 0x7fff)] >> ((~offs & 1) * 4);
+ sprinfo->latched[level] = sprite_expand[pixdata & 0x0f] << level;
+ sprinfo->plb[level] = (plb_end[pixdata & 0x0f] & 1) << level;
+
+ /* if bit 3 is 0 and bit 2 is 1, the enable flip/flip is reset */
+ if (plb_end[pixdata & 0x0f] & 2)
+ sprinfo->lst &= ~(1 << level);
+
+ /* if bit 15 is set, we decrement instead of increment */
+ sprinfo->offset[level] += (offs & 0x10000) ? -1 : 1;
+ sprinfo->frac[level] -= 0x800000;
+ }
+ }
+
+ return sprdata;
+}
+
+
+
+/*************************************
+ *
+ * Subroc 3D video update
+ *
+ *************************************/
+
+VIDEO_UPDATE( subroc3d )
+{
+ turbo_state *state = machine->driver_data;
+ mame_bitmap *fgpixmap = tilemap_get_pixmap(state->fg_tilemap);
+ const UINT8 *prom_base = memory_region(REGION_PROMS);
+ const UINT8 *pr1419 = prom_base + 0x000;
+ const UINT8 *pr1620 = prom_base + 0x200;
+ const UINT8 *pr1450 = prom_base + 0x500;
+ const UINT8 *pr1454 = prom_base + 0x920;
+ int x, y;
+
+ /* loop over rows */
+ for (y = cliprect->min_y; y <= cliprect->max_y; y++)
+ {
+ const UINT16 *fore = (UINT16 *)fgpixmap->base + y * fgpixmap->rowpixels;
+ UINT16 *dest = (UINT16 *)bitmap->base + y * bitmap->rowpixels;
+ sprite_info sprinfo;
+
+ /* compute the sprite information; we use y-1 since this info was computed during HBLANK */
+ /* on the previous scanline */
+ subroc3d_prepare_sprites(state, y, &sprinfo);
+
+ /* loop over columns */
+ for (x = 0; x <= cliprect->max_x; x += TURBO_X_SCALE)
+ {
+ int offs, finalbits, ix;
+ UINT8 xx = x / TURBO_X_SCALE;
+ UINT8 foreraw, forebits, mux, cd, plb, mplb;
+ UINT16 he;
+ UINT32 sprbits;
+
+ /* load the bitmask from the sprite position for both halves of the sprites (p. 143) */
+ he = state->sprite_position[xx * 2] | (state->sprite_position[xx * 2 + 1] << 8);
+
+ /* the AND of the line enable and horizontal enable is clocked and held in LST0-7 (p. 143) */
+ he &= sprinfo.ve;
+ sprinfo.lst |= he | (he >> 8);
+
+ /* at this point, do the character lookup */
+ if (!state->subroc3d_flip)
+ foreraw = fore[xx];
+ else
+ foreraw = fore[(pr1454[(xx >> 3) & 0x1f] << 3) | (xx & 0x07)];
+
+ /* perform the foreground color table lookup in IC62/PR1620 (p. 141) */
+ forebits = pr1620[foreraw];
+
+ /* MPLB is set based on the high bit of the raw foreground data, as an OR over the output */
+ /* of the foreground color PROM */
+ mplb = (foreraw & 0x80) || ((forebits & 0x0f) == 0);
+
+ /* now that we have done all the per-5MHz pixel work, mix the sprites at the scale factor */
+ for (ix = 0; ix < TURBO_X_SCALE; ix++)
+ {
+ /* iterate over live sprites and update them */
+ /* the final 32-bit value is: */
+ /* CDA0-7 = D0 -D7 */
+ /* CDB0-7 = D8 -D15 */
+ /* CDC0-7 = D16-D23 */
+ /* CDD0-7 = D24-D31 */
+ sprbits = subroc3d_get_sprite_bits(&sprinfo, &plb);
+
+ /* MUX0-3 is selected by PLY0-3 and the sprite enable bits, and is the output */
+ /* of IC21/PR1450 (p. 141), unless MPLB = 0, in which case the values are grounded (p. 141) */
+ if (mplb)
+ {
+ offs = (plb ^ 0xff) | /* A0-A7: /PLB0-7 */
+ ((state->subroc3d_ply & 0x02) << 7); /* A8: PLY1 */
+ mux = pr1450[offs] >> ((state->subroc3d_ply & 0x01) * 4);
+ }
+ else
+ mux = 0;
+
+ /* CD0-3 are selected from the sprite bits and MUX0-2 (p. 141) */
+ sprbits = (sprbits >> (mux & 0x07)) & 0x01010101;
+ cd = (sprbits >> (24-3)) | (sprbits >> (16-2)) | (sprbits >> (8-1)) | sprbits;
+
+ /* MUX3 selects either CD0-3 or the foreground output (p. 141) */
+ if (mux & 0x08)
+ finalbits = cd;
+ else
+ finalbits = forebits;
+
+ /* we then go through a muxer to select one of the 16 outputs computed above (p. 141) */
+ offs = (finalbits & 0x0f) | /* A0-A3: CD0-CD3 */
+ ((mux & 0x08) << 1) | /* A4: MUX3 */
+ (state->subroc3d_col << 5); /* A5-A8: COL0-COL3 */
+ dest[x + ix] = pr1419[offs];
+ }
+ }
+ }
+ return 0;
+}
+
+
+
+/*************************************
+ *
+ * Buck Rogers sprite handling
+ *
+ *************************************/
+
+static void buckrog_prepare_sprites(turbo_state *state, UINT8 y, sprite_info *info)
+{
+ const UINT8 *pr5196 = memory_region(REGION_PROMS) + 0x100;
+ int sprnum;
+
+ /* initialize the line enable signals to 0 */
+ info->ve = 0;
+ info->lst = 0;
+
+ /* compute the sprite information, which was done on the previous scanline during HBLANK */
+ for (sprnum = 0; sprnum < 16; sprnum++)
+ {
+ UINT8 *rambase = &state->spriteram[sprnum * 8];
+ int level = sprnum & 7;
+ UINT8 clo, chi;
+ UINT32 sum;
+
+ /* perform the first ALU to see if we are within the scanline */
+ sum = y + (rambase[0]/* ^ 0xff*/);
+ clo = (sum >> 8) & 1;
+ sum += (y << 8) + ((rambase[1]/* ^ 0xff*/) << 8);
+ chi = (sum >> 16) & 1;
+
+ /* the AND of the low carry and the inverse of the high carry clocks an enable bit */
+ /* for this sprite; note that the logic in the Turbo schematics is reversed here */
+ if (clo & (chi ^ 1))
+ {
+ int xscale = rambase[2] ^ 0xff;
+ int yscale = rambase[3];// ^ 0xff;
+ UINT16 offset = rambase[6] + (rambase[7] << 8);
+ int offs;
+
+ /* mark this entry enabled */
+ info->ve |= 1 << sprnum;
+
+ /* look up the low byte of the sum plus the yscale value in */
+ /* IC50/PR1119 to determine if we write back the sum of the */
+ /* offset and the rowbytes this scanline (p. 138) */
+ offs = (sum & 0xff) | /* A0-A7 = AL0-AL7 */
+ ((yscale & 0x08) << 5); /* A8-A9 = /RO11-/RO12 */
+
+ /* one of the bits is selected based on the low 7 bits of yscale */
+ if (!((pr5196[offs] >> (yscale & 0x07)) & 1))
+ {
+ offset += rambase[4] + (rambase[5] << 8);
+ rambase[6] = offset;
+ rambase[7] = offset >> 8;
+ }
+
+ /* the output of the ALU here goes to the individual level counter */
+ info->latched[level] = 0;
+ info->plb[level] = 0;
+ info->offset[level] = offset << 1;
+ info->frac[level] = 0;
+ info->step[level] = sprite_xscale(xscale, 1.2e3, 500/*820*/, 220e-12);
+ }
+ }
+}
+
+
+static UINT32 buckrog_get_sprite_bits(sprite_info *sprinfo, UINT8 *plb)
+{
+ /* see logic on each sprite:
+ END = (CDA == 1 && (CDA ^ CDB) == 0 && (CDC ^ CDD) == 0)
+ PLB = END ^ (CDA == 1 && (CDC ^ CDD) == 0)
+ end is in bit 1, plb in bit 0
+ */
+ static const UINT8 plb_end[16] = { 0,1,1,1, 1,1,1,1, 1,1,1,1, 1,1,1,2 };
+ const UINT8 *sprite_gfxdata = memory_region(REGION_GFX1);
+ UINT32 sprdata = 0;
+ int level;
+
+ *plb = 0;
+
+ /* loop over all live levels */
+ for (level = 0; level < 8; level++)
+ if (sprinfo->lst & (1 << level))
+ {
+ /* latch the data and advance the offset */
+ sprdata |= sprinfo->latched[level];
+ *plb |= sprinfo->plb[level];
+ sprinfo->frac[level] += sprinfo->step[level];
+
+ /* if we're live and we've clocked more data, advance */
+ while (sprinfo->frac[level] >= 0x800000)
+ {
+ UINT32 offs = sprinfo->offset[level];
+ UINT8 pixdata;
+
+ /* bit 0 controls which half of the byte to use */
+ /* bits 1-13 go to address lines */
+ /* bit 14 selects which of the two ROMs to read from */
+ pixdata = sprite_gfxdata[(level << 15) | ((offs >> 1) & 0x7fff)] >> ((~offs & 1) * 4);
+ sprinfo->latched[level] = sprite_expand[pixdata & 0x0f] << level;
+ sprinfo->plb[level] = (plb_end[pixdata & 0x0f] & 1) << level;
+
+ /* if bit 3 is 0 and bit 2 is 1, the enable flip/flip is reset */
+ if (plb_end[pixdata & 0x0f] & 2)
+ sprinfo->lst &= ~(1 << level);
+
+ /* if bit 15 is set, we decrement instead of increment */
+ sprinfo->offset[level] += (offs & 0x10000) ? -1 : 1;
+ sprinfo->frac[level] -= 0x800000;
+ }
+ }
+
+ return sprdata;
+}
+
+
+
+/*************************************
+ *
+ * Buck Rogers video update
+ *
+ *************************************/
+
+VIDEO_UPDATE( buckrog )
+{
+ turbo_state *state = machine->driver_data;
+ mame_bitmap *fgpixmap = tilemap_get_pixmap(state->fg_tilemap);
+ const UINT8 *bgcolor = memory_region(REGION_GFX3);
+ const UINT8 *prom_base = memory_region(REGION_PROMS);
+ const UINT8 *pr5194 = prom_base + 0x000;
+ const UINT8 *pr5198 = prom_base + 0x500;
+ const UINT8 *pr5199 = prom_base + 0x700;
+ int x, y;
+
+ /* loop over rows */
+ for (y = cliprect->min_y; y <= cliprect->max_y; y++)
+ {
+ const UINT16 *fore = (UINT16 *)fgpixmap->base + y * fgpixmap->rowpixels;
+ UINT16 *dest = (UINT16 *)bitmap->base + y * bitmap->rowpixels;
+ sprite_info sprinfo;
+
+ /* compute the sprite information; we use y-1 since this info was computed during HBLANK */
+ /* on the previous scanline */
+ buckrog_prepare_sprites(state, y, &sprinfo);
+
+ /* loop over columns */
+ for (x = 0; x <= cliprect->max_x; x += TURBO_X_SCALE)
+ {
+ UINT8 foreraw, forebits, cd, plb, star, mux;
+ UINT8 xx = x / TURBO_X_SCALE;
+ UINT16 he;
+ UINT32 sprbits;
+ int palbits, offs, ix;
+
+ /* load the bitmask from the sprite position for both halves of the sprites (p. 143) */
+ he = state->sprite_position[xx * 2] | (state->sprite_position[xx * 2 + 1] << 8);
+
+ /* the AND of the line enable and horizontal enable is clocked and held in LST0-7 (p. 143) */
+ he &= sprinfo.ve;
+ sprinfo.lst |= he | (he >> 8);
+
+ /* at this point, do the character lookup and the foreground color table lookup in IC93/PR1598 (SH 5/5)*/
+ foreraw = fore[(pr5194[((xx >> 3) - 1) & 0x1f] << 3) | (xx & 0x07)];
+ offs = ((foreraw & 0x03) << 0) | /* A0-A1: BIT0-1 */
+ ((foreraw & 0xf8) >> 1) | /* A2-A6: BANK3-7 */
+ ((state->buckrog_fchg & 0x03) << 7); /* A7-A9: FCHG0-2 */
+ forebits = pr5198[offs];
+
+ /* fetch the STAR bit */
+ star = state->buckrog_bitmap_ram[y * 256 + xx];
+
+ /* now that we have done all the per-5MHz pixel work, mix the sprites at the scale factor */
+ for (ix = 0; ix < TURBO_X_SCALE; ix++)
+ {
+ /* iterate over live sprites and update them */
+ /* the final 32-bit value is: */
+ /* CDA0-7 = D0 -D7 */
+ /* CDB0-7 = D8 -D15 */
+ /* CDC0-7 = D16-D23 */
+ /* CDD0-7 = D24-D31 */
+ sprbits = buckrog_get_sprite_bits(&sprinfo, &plb);
+
+ /* the PLB bits go into an LS148 8-to-1 decoder and become MUX0-3 (PROM board SH 2/10) */
+ if (plb == 0)
+ mux = 8;
+ else
+ {
+ mux = 7;
+ while (!(plb & 0x80))
+ {
+ mux--;
+ plb <<= 1;
+ }
+ }
+
+ /* MUX then selects one of the sprites and selects CD0-3 */
+ sprbits = (sprbits >> (mux & 0x07)) & 0x01010101;
+ cd = (sprbits >> (24-3)) | (sprbits >> (16-2)) | (sprbits >> (8-1)) | sprbits;
+
+ /* this info goes into an LS148 8-to-3 decoder to determine the priorities (SH 5/5) */
+
+ /* priority 7 is if bit 0x80 of the foreground color is 0; CHNG = 0 */
+ if (!(forebits & 0x80))
+ {
+ palbits = ((forebits & 0x3c) << 2) |
+ ((forebits & 0x06) << 1) |
+ ((forebits & 0x01) << 0);
+ }
+
+ /* priority 6 is if MUX3 is 0; CHNG = 1 */
+ else if (!(mux & 0x08))
+ {
+ offs = (cd & 0x0f) | /* A0-A3: CD0-3 */
+ ((mux & 0x07) << 4) | /* A4-A6: MUX0-2 */
+ ((state->buckrog_obch & 0x07) << 7); /* A7-A9: OBCH0-2 */
+ palbits = pr5199[offs];
+ }
+
+ /* priority 3 is if bit 0x40 of the foreground color is 0; CHNG = 0 */
+ else if (!(forebits & 0x40))
+ {
+ palbits = ((forebits & 0x3c) << 2) |
+ ((forebits & 0x06) << 1) |
+ ((forebits & 0x01) << 0);
+ }
+
+ /* priority 1 is if the star is set; CHNG = 2 */
+ else if (star)
+ {
+ palbits = 0xff;
+ }
+
+ /* otherwise, CHNG = 3 */
+ else
+ {
+ palbits = bgcolor[y | ((state->buckrog_mov & 0x1f) << 8)];
+ palbits = (palbits & 0xc0) | ((palbits & 0x30) << 4) | ((palbits & 0x0f) << 2);
+ }
+
+ /* store the final bits for this pixel */
+ dest[x + ix] = palbits;
+ }
+ }
+ }
+ return 0;
+}