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-rw-r--r--src/mame/video/amiga.c971
1 files changed, 971 insertions, 0 deletions
diff --git a/src/mame/video/amiga.c b/src/mame/video/amiga.c
new file mode 100644
index 00000000000..93c3a2df0cc
--- /dev/null
+++ b/src/mame/video/amiga.c
@@ -0,0 +1,971 @@
+/***************************************************************************
+
+ Amiga hardware
+
+ Driver by: Ernesto Corvi, Mariusz Wojcieszek, Aaron Giles
+
+***************************************************************************/
+
+#include "driver.h"
+#include "includes/amiga.h"
+
+
+
+/*************************************
+ *
+ * Debugging
+ *
+ *************************************/
+
+#define LOG_COPPER 0
+#define GUESS_COPPER_OFFSET 0
+#define LOG_SPRITE_DMA 0
+
+
+
+/*************************************
+ *
+ * Macros
+ *
+ *************************************/
+
+#define COPPER_CYCLES_TO_PIXELS(x) (4 * (x))
+
+
+
+/*************************************
+ *
+ * Statics
+ *
+ *************************************/
+
+/* sprite states */
+static UINT8 sprite_comparitor_enable_mask;
+static UINT8 sprite_dma_reload_mask;
+static UINT8 sprite_dma_live_mask;
+static UINT32 sprite_shiftreg[8];
+static UINT8 sprite_remain[8];
+
+/* playfield states */
+static int last_scanline;
+static UINT16 ham_color;
+
+/* copper states */
+static UINT32 copper_pc;
+static UINT8 copper_waiting;
+static UINT8 copper_waitblit;
+static UINT16 copper_waitval;
+static UINT16 copper_waitmask;
+static UINT16 copper_pending_offset;
+static UINT16 copper_pending_data;
+
+/* misc states */
+static UINT16 genlock_color;
+
+#if GUESS_COPPER_OFFSET
+static int wait_offset = 3;
+#endif
+
+
+
+/*************************************
+ *
+ * Tables
+ *
+ *************************************/
+
+/* expand an 8-bit bit pattern into 16 bits, every other bit */
+static const UINT16 expand_byte[256] =
+{
+ 0x0000, 0x0001, 0x0004, 0x0005, 0x0010, 0x0011, 0x0014, 0x0015,
+ 0x0040, 0x0041, 0x0044, 0x0045, 0x0050, 0x0051, 0x0054, 0x0055,
+ 0x0100, 0x0101, 0x0104, 0x0105, 0x0110, 0x0111, 0x0114, 0x0115,
+ 0x0140, 0x0141, 0x0144, 0x0145, 0x0150, 0x0151, 0x0154, 0x0155,
+ 0x0400, 0x0401, 0x0404, 0x0405, 0x0410, 0x0411, 0x0414, 0x0415,
+ 0x0440, 0x0441, 0x0444, 0x0445, 0x0450, 0x0451, 0x0454, 0x0455,
+ 0x0500, 0x0501, 0x0504, 0x0505, 0x0510, 0x0511, 0x0514, 0x0515,
+ 0x0540, 0x0541, 0x0544, 0x0545, 0x0550, 0x0551, 0x0554, 0x0555,
+ 0x1000, 0x1001, 0x1004, 0x1005, 0x1010, 0x1011, 0x1014, 0x1015,
+ 0x1040, 0x1041, 0x1044, 0x1045, 0x1050, 0x1051, 0x1054, 0x1055,
+ 0x1100, 0x1101, 0x1104, 0x1105, 0x1110, 0x1111, 0x1114, 0x1115,
+ 0x1140, 0x1141, 0x1144, 0x1145, 0x1150, 0x1151, 0x1154, 0x1155,
+ 0x1400, 0x1401, 0x1404, 0x1405, 0x1410, 0x1411, 0x1414, 0x1415,
+ 0x1440, 0x1441, 0x1444, 0x1445, 0x1450, 0x1451, 0x1454, 0x1455,
+ 0x1500, 0x1501, 0x1504, 0x1505, 0x1510, 0x1511, 0x1514, 0x1515,
+ 0x1540, 0x1541, 0x1544, 0x1545, 0x1550, 0x1551, 0x1554, 0x1555,
+
+ 0x4000, 0x4001, 0x4004, 0x4005, 0x4010, 0x4011, 0x4014, 0x4015,
+ 0x4040, 0x4041, 0x4044, 0x4045, 0x4050, 0x4051, 0x4054, 0x4055,
+ 0x4100, 0x4101, 0x4104, 0x4105, 0x4110, 0x4111, 0x4114, 0x4115,
+ 0x4140, 0x4141, 0x4144, 0x4145, 0x4150, 0x4151, 0x4154, 0x4155,
+ 0x4400, 0x4401, 0x4404, 0x4405, 0x4410, 0x4411, 0x4414, 0x4415,
+ 0x4440, 0x4441, 0x4444, 0x4445, 0x4450, 0x4451, 0x4454, 0x4455,
+ 0x4500, 0x4501, 0x4504, 0x4505, 0x4510, 0x4511, 0x4514, 0x4515,
+ 0x4540, 0x4541, 0x4544, 0x4545, 0x4550, 0x4551, 0x4554, 0x4555,
+ 0x5000, 0x5001, 0x5004, 0x5005, 0x5010, 0x5011, 0x5014, 0x5015,
+ 0x5040, 0x5041, 0x5044, 0x5045, 0x5050, 0x5051, 0x5054, 0x5055,
+ 0x5100, 0x5101, 0x5104, 0x5105, 0x5110, 0x5111, 0x5114, 0x5115,
+ 0x5140, 0x5141, 0x5144, 0x5145, 0x5150, 0x5151, 0x5154, 0x5155,
+ 0x5400, 0x5401, 0x5404, 0x5405, 0x5410, 0x5411, 0x5414, 0x5415,
+ 0x5440, 0x5441, 0x5444, 0x5445, 0x5450, 0x5451, 0x5454, 0x5455,
+ 0x5500, 0x5501, 0x5504, 0x5505, 0x5510, 0x5511, 0x5514, 0x5515,
+ 0x5540, 0x5541, 0x5544, 0x5545, 0x5550, 0x5551, 0x5554, 0x5555
+};
+
+/* separate 6 in-order bitplanes into 2 x 3-bit bitplanes in two nibbles */
+static UINT8 separate_bitplanes[2][64];
+
+
+
+/*************************************
+ *
+ * 4-4-4 palette init
+ *
+ *************************************/
+
+PALETTE_INIT( amiga )
+{
+ int i;
+
+ for (i = 0; i < 0x1000; i++)
+ palette_set_color_rgb(machine, i, pal4bit(i >> 8), pal4bit(i >> 4), pal4bit(i));
+}
+
+
+
+/*************************************
+ *
+ * Video startup
+ *
+ *************************************/
+
+VIDEO_START( amiga )
+{
+ int j;
+
+ /* generate tables that produce the correct playfield color for dual playfield mode */
+ for (j = 0; j < 64; j++)
+ {
+ int pf1pix = ((j >> 0) & 1) | ((j >> 1) & 2) | ((j >> 2) & 4);
+ int pf2pix = ((j >> 1) & 1) | ((j >> 2) & 2) | ((j >> 3) & 4);
+
+ separate_bitplanes[0][j] = (pf1pix || !pf2pix) ? pf1pix : (pf2pix + 8);
+ separate_bitplanes[1][j] = pf2pix ? (pf2pix + 8) : pf1pix;
+ }
+
+ /* reset the genlock color */
+ genlock_color = 0xffff;
+
+ video_start_generic_bitmapped(machine);
+}
+
+
+
+/*************************************
+ *
+ * Beam position
+ *
+ *************************************/
+
+UINT32 amiga_gethvpos(void)
+{
+ UINT32 hvpos = (last_scanline << 8) | (video_screen_get_hpos(0) >> 2);
+ UINT32 latchedpos = readinputportbytag_safe("HVPOS", 0);
+
+ /* if there's no latched position, or if we are in the active display area */
+ /* but before the latching point, return the live HV position */
+ if ((CUSTOM_REG(REG_BPLCON0) & 0x0008) == 0 || latchedpos == 0 || (last_scanline >= 20 && hvpos < latchedpos))
+ return hvpos;
+
+ /* otherwise, return the latched position */
+ return latchedpos;
+}
+
+
+
+/*************************************
+ *
+ * Genlock interaction
+ *
+ *************************************/
+
+void amiga_set_genlock_color(UINT16 color)
+{
+ genlock_color = color;
+}
+
+
+
+/*************************************
+ *
+ * Copper emulation
+ *
+ *************************************/
+
+void copper_setpc(UINT32 pc)
+{
+ if (LOG_COPPER)
+ logerror("copper_setpc(%06x)\n", pc);
+
+ copper_pc = pc;
+ copper_waiting = FALSE;
+}
+
+
+static int copper_execute_next(int xpos)
+{
+ int word0, word1;
+
+ /* bail if not enabled */
+ if ((CUSTOM_REG(REG_DMACON) & (DMACON_COPEN | DMACON_DMAEN)) != (DMACON_COPEN | DMACON_DMAEN))
+ return 511;
+
+ /* flush any pending writes */
+ if (copper_pending_offset)
+ {
+ if (LOG_COPPER)
+ logerror("%02X.%02X: Write to %s = %04x\n", last_scanline, xpos / 2, amiga_custom_names[copper_pending_offset & 0xff], copper_pending_data);
+
+ amiga_custom_w(copper_pending_offset, copper_pending_data, 0);
+ copper_pending_offset = 0;
+ }
+
+ /* if we're waiting, check for a breakthrough */
+ if (copper_waiting)
+ {
+ int curpos = (last_scanline << 8) | (xpos >> 1);
+
+ /* if we're past the wait time, stop it and hold up 2 cycles */
+ if ((curpos & copper_waitmask) >= (copper_waitval & copper_waitmask) &&
+ (!copper_waitblit || !(CUSTOM_REG(REG_DMACON) & DMACON_BBUSY)))
+ {
+ copper_waiting = FALSE;
+#if GUESS_COPPER_OFFSET
+ return xpos + COPPER_CYCLES_TO_PIXELS(1 + wait_offset);
+#else
+ return xpos + COPPER_CYCLES_TO_PIXELS(1 + 3);
+#endif
+ }
+
+ /* otherwise, see if this line is even a possibility; if not, punt */
+ if (((curpos | 0xff) & copper_waitmask) < (copper_waitval & copper_waitmask))
+ return 511;
+
+ /* else just advance another pixel */
+ xpos += COPPER_CYCLES_TO_PIXELS(1);
+ return xpos;
+ }
+
+ /* fetch the first data word */
+ word0 = amiga_chip_ram_r(copper_pc);
+ copper_pc += 2;
+ xpos += COPPER_CYCLES_TO_PIXELS(1);
+
+ /* fetch the second data word */
+ word1 = amiga_chip_ram_r(copper_pc);
+ copper_pc += 2;
+ xpos += COPPER_CYCLES_TO_PIXELS(1);
+
+ if (LOG_COPPER)
+ logerror("%02X.%02X: Copper inst @ %06x = %04x %04x\n", last_scanline, xpos / 2, copper_pc, word0, word1);
+
+ /* handle a move */
+ if ((word0 & 1) == 0)
+ {
+ int min = (CUSTOM_REG(REG_COPCON) & 2) ? 0x20 : 0x40;
+
+ /* do the write if we're allowed */
+ word0 = (word0 >> 1) & 0xff;
+ if (word0 >= min)
+ {
+ /* write it at the *end* of this instruction's cycles */
+ /* needed for Arcadia's Fast Break */
+ copper_pending_offset = word0;
+ copper_pending_data = word1;
+ }
+
+ /* illegal writes suspend until next frame */
+ else
+ {
+ if (LOG_COPPER)
+ logerror("%02X.%02X: Aborting copper on illegal write\n", last_scanline, xpos / 2);
+
+ copper_waitval = 0xffff;
+ copper_waitmask = 0xffff;
+ copper_waitblit = FALSE;
+ copper_waiting = TRUE;
+ return 511;
+ }
+ }
+ else
+ {
+ /* extract common wait/skip values */
+ copper_waitval = word0 & 0xfffe;
+ copper_waitmask = word1 | 0x8001;
+ copper_waitblit = (~word1 >> 15) & 1;
+
+ /* handle a wait */
+ if ((word1 & 1) == 0)
+ {
+ if (LOG_COPPER)
+ logerror(" Waiting for %04x & %04x (currently %04x)\n", copper_waitval, copper_waitmask, (last_scanline << 8) | (xpos >> 1));
+
+ copper_waiting = TRUE;
+ }
+
+ /* handle a skip */
+ else
+ {
+ int curpos = (last_scanline << 8) | (xpos >> 1);
+
+ if (LOG_COPPER)
+ logerror(" Skipping if %04x & %04x (currently %04x)\n", copper_waitval, copper_waitmask, (last_scanline << 8) | (xpos >> 1));
+
+ /* if we're past the wait time, stop it and hold up 2 cycles */
+ if ((curpos & copper_waitmask) >= (copper_waitval & copper_waitmask) &&
+ (!copper_waitblit || !(CUSTOM_REG(REG_DMACON) & DMACON_BBUSY)))
+ {
+ if (LOG_COPPER)
+ logerror(" Skipped\n");
+
+ /* count the cycles it out have taken to fetch the next instruction */
+ copper_pc += 4;
+ xpos += COPPER_CYCLES_TO_PIXELS(2);
+ }
+ }
+ }
+
+ /* advance and consume 8 cycles */
+ return xpos;
+}
+
+
+
+/*************************************
+ *
+ * External sprite controls
+ *
+ *************************************/
+
+void amiga_sprite_dma_reset(int which)
+{
+ sprite_dma_reload_mask |= 1 << which;
+ sprite_dma_live_mask |= 1 << which;
+}
+
+
+void amiga_sprite_enable_comparitor(int which, int enable)
+{
+ if (enable)
+ {
+ sprite_comparitor_enable_mask |= 1 << which;
+ sprite_dma_live_mask &= ~(1 << which);
+ }
+ else
+ sprite_comparitor_enable_mask &= ~(1 << which);
+}
+
+
+
+/*************************************
+ *
+ * Per-scanline sprite fetcher
+ *
+ *************************************/
+
+static void update_sprite_dma(int scanline)
+{
+ int dmaenable = (CUSTOM_REG(REG_DMACON) & (DMACON_SPREN | DMACON_DMAEN)) == (DMACON_SPREN | DMACON_DMAEN);
+ int num, maxdma;
+
+ /* channels are limited by DDFSTART */
+ maxdma = (CUSTOM_REG(REG_DDFSTRT) - 0x14) / 4;
+ if (maxdma > 8)
+ maxdma = 8;
+
+ /* loop over sprite channels */
+ for (num = 0; num < maxdma; num++)
+ {
+ int bitmask = 1 << num;
+ int vstart, vstop;
+
+ /* if we are == VSTOP, fetch new control words */
+ if (dmaenable && (sprite_dma_live_mask & bitmask) && (sprite_dma_reload_mask & bitmask))
+ {
+ /* disable the sprite */
+ sprite_comparitor_enable_mask &= ~bitmask;
+ sprite_dma_reload_mask &= ~bitmask;
+
+ /* fetch data into the control words */
+ CUSTOM_REG(REG_SPR0POS + 4 * num) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_SPR0PTH + 2 * num) + 0);
+ CUSTOM_REG(REG_SPR0CTL + 4 * num) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_SPR0PTH + 2 * num) + 2);
+ CUSTOM_REG_LONG(REG_SPR0PTH + 2 * num) += 4;
+ if (LOG_SPRITE_DMA) logerror("%3d:sprite %d fetch: pos=%04X ctl=%04X\n", scanline, num, CUSTOM_REG(REG_SPR0POS + 4 * num), CUSTOM_REG(REG_SPR0CTL + 4 * num));
+ }
+
+ /* compute vstart/vstop */
+ vstart = (CUSTOM_REG(REG_SPR0POS + 4 * num) >> 8) | ((CUSTOM_REG(REG_SPR0CTL + 4 * num) << 6) & 0x100);
+ vstop = (CUSTOM_REG(REG_SPR0CTL + 4 * num) >> 8) | ((CUSTOM_REG(REG_SPR0CTL + 4 * num) << 7) & 0x100);
+
+ /* if we hit vstart, enable the comparitor */
+ if (scanline == vstart)
+ {
+ sprite_comparitor_enable_mask |= 1 << num;
+ if (LOG_SPRITE_DMA) logerror("%3d:sprite %d comparitor enable\n", scanline, num);
+ }
+
+ /* if we hit vstop, disable the comparitor and trigger a reload for the next scanline */
+ if (scanline == vstop)
+ {
+ sprite_comparitor_enable_mask &= ~bitmask;
+ sprite_dma_reload_mask |= 1 << num;
+ CUSTOM_REG(REG_SPR0DATA + 4 * num) = 0; /* just a guess */
+ CUSTOM_REG(REG_SPR0DATB + 4 * num) = 0;
+ if (LOG_SPRITE_DMA) logerror("%3d:sprite %d comparitor disable, prepare for reload\n", scanline, num);
+ }
+
+ /* fetch data if this sprite is enabled */
+ if (dmaenable && (sprite_dma_live_mask & bitmask) && (sprite_comparitor_enable_mask & bitmask))
+ {
+ CUSTOM_REG(REG_SPR0DATA + 4 * num) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_SPR0PTH + 2 * num) + 0);
+ CUSTOM_REG(REG_SPR0DATB + 4 * num) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_SPR0PTH + 2 * num) + 2);
+ CUSTOM_REG_LONG(REG_SPR0PTH + 2 * num) += 4;
+ if (LOG_SPRITE_DMA) logerror("%3d:sprite %d fetch: data=%04X-%04X\n", scanline, num, CUSTOM_REG(REG_SPR0DATA + 4 * num), CUSTOM_REG(REG_SPR0DATB + 4 * num));
+ }
+ }
+}
+
+
+
+/*************************************
+ *
+ * Per-pixel sprite computations
+ *
+ *************************************/
+
+INLINE UINT32 interleave_sprite_data(UINT16 lobits, UINT16 hibits)
+{
+ return (expand_byte[lobits & 0xff] << 0) | (expand_byte[lobits >> 8] << 16) |
+ (expand_byte[hibits & 0xff] << 1) | (expand_byte[hibits >> 8] << 17);
+}
+
+
+static int get_sprite_pixel(int x)
+{
+ int pixels = 0;
+ int num, pair;
+
+ /* loop over sprite channels */
+ for (num = 0; num < 8; num++)
+ if (sprite_comparitor_enable_mask & (1 << num))
+ {
+ /* if we're not currently clocking, check against hstart */
+ if (sprite_remain[num] == 0)
+ {
+ int hstart = ((CUSTOM_REG(REG_SPR0POS + 4 * num) & 0xff) << 1) | (CUSTOM_REG(REG_SPR0CTL + 4 * num) & 1);
+ if (hstart == x)
+ {
+ sprite_remain[num] = 16;
+ sprite_shiftreg[num] = interleave_sprite_data(CUSTOM_REG(REG_SPR0DATA + 4 * num), CUSTOM_REG(REG_SPR0DATB + 4 * num));
+ }
+ }
+
+ /* clock the next pixel if we're doing it */
+ if (sprite_remain[num] != 0)
+ {
+ sprite_remain[num]--;
+ pixels |= (sprite_shiftreg[num] & 0xc0000000) >> (16 + 2 * (7 - num));
+ sprite_shiftreg[num] <<= 2;
+ }
+ }
+
+ /* if we have pixels, determine the actual color and get out */
+ if (pixels)
+ {
+ static const UINT16 ormask[16] =
+ {
+ 0x0000, 0x000c, 0x00c0, 0x00cc, 0x0c00, 0x0c0c, 0x0cc0, 0x0ccc,
+ 0xc000, 0xc00c, 0xc0c0, 0xc0cc, 0xcc00, 0xcc0c, 0xccc0, 0xcccc
+ };
+ static const UINT16 spritecollide[16] =
+ {
+ 0x0000, 0x0000, 0x0000, 0x0200, 0x0000, 0x0400, 0x1000, 0x1600,
+ 0x0000, 0x0800, 0x2000, 0x2a00, 0x4000, 0x4c00, 0x7000, 0x7e00
+ };
+ int collide;
+
+ /* OR the two sprite bits together so we only have 1 bit per sprite */
+ collide = pixels | (pixels >> 1);
+
+ /* based on the CLXCON, merge even/odd sprite results */
+ collide |= (collide & ormask[CUSTOM_REG(REG_CLXCON) >> 12]) >> 2;
+
+ /* collapse down to a 4-bit final "sprite present" mask */
+ collide = (collide & 1) | ((collide >> 3) & 2) | ((collide >> 6) & 4) | ((collide >> 9) & 8);
+
+ /* compute sprite-sprite collisions */
+ CUSTOM_REG(REG_CLXDAT) |= spritecollide[collide];
+
+ /* now determine the actual color */
+ for (pair = 0; pixels; pair++, pixels >>= 4)
+ if (pixels & 0x0f)
+ {
+ /* final result is:
+ topmost sprite color in bits 0-5
+ sprite present bitmask in bits 6-9
+ topmost sprite pair index in bits 10-11
+ */
+
+ /* attached case */
+ if (CUSTOM_REG(REG_SPR1CTL + 8 * pair) & 0x0080)
+ return (pixels & 0xf) | 0x10 | (collide << 6) | (pair << 10);
+
+ /* lower-numbered sprite of pair */
+ else if (pixels & 3)
+ return (pixels & 3) | 0x10 | (pair << 2) | (collide << 6) | (pair << 10);
+
+ /* higher-numbered sprite of pair */
+ else
+ return ((pixels >> 2) & 3) | 0x10 | (pair << 2) | (collide << 6) | (pair << 10);
+ }
+ }
+
+ return 0;
+}
+
+
+
+/*************************************
+ *
+ * Bitplane assembly
+ *
+ *************************************/
+
+INLINE UINT8 assemble_odd_bitplanes(int planes, int obitoffs)
+{
+ UINT8 pix = (CUSTOM_REG(REG_BPL1DAT) >> obitoffs) & 1;
+ if (planes >= 3)
+ {
+ pix |= ((CUSTOM_REG(REG_BPL3DAT) >> obitoffs) & 1) << 2;
+ if (planes >= 5)
+ pix |= ((CUSTOM_REG(REG_BPL5DAT) >> obitoffs) & 1) << 4;
+ }
+ return pix;
+}
+
+
+INLINE UINT8 assemble_even_bitplanes(int planes, int ebitoffs)
+{
+ UINT8 pix = 0;
+ if (planes >= 2)
+ {
+ pix |= ((CUSTOM_REG(REG_BPL2DAT) >> ebitoffs) & 1) << 1;
+ if (planes >= 4)
+ {
+ pix |= ((CUSTOM_REG(REG_BPL4DAT) >> ebitoffs) & 1) << 3;
+ if (planes >= 6)
+ pix |= ((CUSTOM_REG(REG_BPL6DAT) >> ebitoffs) & 1) << 5;
+ }
+ }
+ return pix;
+}
+
+
+
+/*************************************
+ *
+ * Hold and modify pixel computations
+ *
+ *************************************/
+
+INLINE int update_ham(int newpix)
+{
+ switch (newpix >> 4)
+ {
+ case 0:
+ ham_color = CUSTOM_REG(REG_COLOR00 + (newpix & 0xf));
+ break;
+
+ case 1:
+ ham_color = (ham_color & 0xff0) | ((newpix & 0xf) << 0);
+ break;
+
+ case 2:
+ ham_color = (ham_color & 0x0ff) | ((newpix & 0xf) << 8);
+ break;
+
+ case 3:
+ ham_color = (ham_color & 0xf0f) | ((newpix & 0xf) << 4);
+ break;
+ }
+ return ham_color;
+}
+
+
+
+/*************************************
+ *
+ * Single scanline rasterizer
+ *
+ *************************************/
+
+void amiga_render_scanline(int scanline)
+{
+ UINT16 save_color0 = CUSTOM_REG(REG_COLOR00);
+ int ddf_start_pixel = 0, ddf_stop_pixel = 0;
+ int hires = 0, dualpf = 0, lace = 0, ham = 0;
+ int hstart = 0, hstop = 0;
+ int vstart = 0, vstop = 0;
+ int pf1pri = 0, pf2pri = 0;
+ int planes = 0;
+
+ int x;
+ UINT16 *dst;
+ int ebitoffs = 0, obitoffs = 0;
+ int ecolmask = 0, ocolmask = 0;
+ int edelay = 0, odelay = 0;
+ int next_copper_x;
+ int p;
+
+ last_scanline = scanline;
+
+ /* on the first scanline, reset the COPPER and HAM color */
+ if (scanline == 0)
+ {
+ copper_setpc(CUSTOM_REG_LONG(REG_COP1LCH));
+ ham_color = CUSTOM_REG(REG_COLOR00);
+ }
+
+ /* update sprite data fetching */
+ update_sprite_dma(scanline);
+
+ /* start of a new line, signal we're not done with it and fill up vars */
+ dst = BITMAP_ADDR16(tmpbitmap, scanline, 0);
+
+ /* all sprites off at the start of the line */
+ memset(sprite_remain, 0, sizeof(sprite_remain));
+
+ /* temporary set color 0 to the genlock color */
+ if (genlock_color != 0xffff)
+ CUSTOM_REG(REG_COLOR00) = genlock_color;
+
+ /* loop over the line */
+ next_copper_x = 2; /* copper runs on odd timeslots */
+ for (x = 0; x < 0xe4*2; x++)
+ {
+ int sprpix;
+
+ /* time to execute the copper? */
+ if (x == next_copper_x)
+ {
+ /* execute the next batch, restoring and re-saving color 0 around it */
+ CUSTOM_REG(REG_COLOR00) = save_color0;
+ next_copper_x = copper_execute_next(x);
+ save_color0 = CUSTOM_REG(REG_COLOR00);
+ if (genlock_color != 0xffff)
+ CUSTOM_REG(REG_COLOR00) = genlock_color;
+
+ /* compute update-related register values */
+ planes = (CUSTOM_REG(REG_BPLCON0) & (BPLCON0_BPU0 | BPLCON0_BPU1 | BPLCON0_BPU2)) >> 12;
+ hires = CUSTOM_REG(REG_BPLCON0) & BPLCON0_HIRES;
+ ham = CUSTOM_REG(REG_BPLCON0) & BPLCON0_HOMOD;
+ dualpf = CUSTOM_REG(REG_BPLCON0) & BPLCON0_DBLPF;
+ lace = CUSTOM_REG(REG_BPLCON0) & BPLCON0_LACE;
+
+ /* compute the pixel fetch parameters */
+ ddf_start_pixel = ( CUSTOM_REG(REG_DDFSTRT) & 0xfc ) * 2 + (hires ? 9 : 17);
+ ddf_stop_pixel = ( CUSTOM_REG(REG_DDFSTOP) & 0xfc ) * 2 + (hires ? (9 + 15) : (17 + 15));
+
+ if ( ( CUSTOM_REG(REG_DDFSTRT) ^ CUSTOM_REG(REG_DDFSTOP) ) & 0x04 )
+ ddf_stop_pixel += 8;
+
+ /* compute the horizontal start/stop */
+ hstart = CUSTOM_REG(REG_DIWSTRT) & 0xff;
+ hstop = 0x100 + (CUSTOM_REG(REG_DIWSTOP) & 0xff);
+
+ /* compute the vertical start/stop */
+ vstart = CUSTOM_REG(REG_DIWSTRT) >> 8;
+ vstop = (CUSTOM_REG(REG_DIWSTOP) >> 8) | ((~CUSTOM_REG(REG_DIWSTOP) >> 7) & 0x100);
+
+ /* extract playfield priorities */
+ pf1pri = CUSTOM_REG(REG_BPLCON2) & 7;
+ pf2pri = (CUSTOM_REG(REG_BPLCON2) >> 3) & 7;
+
+ /* extract collision masks */
+ ocolmask = (CUSTOM_REG(REG_CLXCON) >> 6) & 0x15;
+ ecolmask = (CUSTOM_REG(REG_CLXCON) >> 6) & 0x2a;
+ }
+
+ /* clear the target pixels to the background color as a starting point */
+ dst[x*2+0] =
+ dst[x*2+1] = CUSTOM_REG(REG_COLOR00);
+
+ /* if we hit the first fetch pixel, reset the counters and latch the delays */
+ if (x == ddf_start_pixel)
+ {
+ odelay = CUSTOM_REG(REG_BPLCON1) & 0xf;
+ edelay = ( CUSTOM_REG(REG_BPLCON1) >> 4 ) & 0x0f;
+
+ if ( hires )
+ {
+ obitoffs = 15 + ( odelay << 1 );
+ ebitoffs = 15 + ( edelay << 1 );
+ }
+ else
+ {
+ if ( CUSTOM_REG(REG_DDFSTRT) & 0x04 )
+ {
+ odelay = ( odelay + 8 ) & 0x0f;
+ edelay = ( edelay + 8 ) & 0x0f;
+ }
+
+ obitoffs = 15 + odelay;
+ ebitoffs = 15 + edelay;
+ }
+
+ for (p = 0; p < 6; p++)
+ CUSTOM_REG(REG_BPL1DAT + p) = 0;
+ }
+
+ /* need to run the sprite engine every pixel to ensure display */
+ sprpix = get_sprite_pixel(x);
+
+ /* to render, we must have bitplane DMA enabled, at least 1 plane, and be within the */
+ /* vertical display window */
+ if ((CUSTOM_REG(REG_DMACON) & (DMACON_BPLEN | DMACON_DMAEN)) == (DMACON_BPLEN | DMACON_DMAEN) &&
+ planes > 0 && scanline >= vstart && scanline < vstop)
+ {
+ int pfpix0 = 0, pfpix1 = 0, collide;
+
+ /* fetch the odd bits if we are within the fetching region */
+ if (x >= ddf_start_pixel && x <= ddf_stop_pixel + odelay)
+ {
+ /* if we need to fetch more data, do it now */
+ if (obitoffs == 15)
+ for (p = 0; p < planes; p += 2)
+ {
+ CUSTOM_REG(REG_BPL1DAT + p) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_BPL1PTH + p * 2));
+ CUSTOM_REG_LONG(REG_BPL1PTH + p * 2) += 2;
+ }
+
+ /* now assemble the bits */
+ pfpix0 |= assemble_odd_bitplanes(planes, obitoffs);
+ obitoffs--;
+
+ /* for high res, assemble a second set of bits */
+ if (hires)
+ {
+ /* reset bit offsets and fetch more data if needed */
+ if (obitoffs < 0)
+ {
+ obitoffs = 15;
+
+ for (p = 0; p < planes; p += 2)
+ {
+ CUSTOM_REG(REG_BPL1DAT + p) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_BPL1PTH + p * 2));
+ CUSTOM_REG_LONG(REG_BPL1PTH + p * 2) += 2;
+ }
+ }
+
+ pfpix1 |= assemble_odd_bitplanes(planes, obitoffs);
+ obitoffs--;
+ }
+ else
+ pfpix1 |= pfpix0 & 0x15;
+
+ /* reset bit offsets if needed */
+ if (obitoffs < 0)
+ obitoffs = 15;
+ }
+
+ /* fetch the even bits if we are within the fetching region */
+ if (x >= ddf_start_pixel && x <= ddf_stop_pixel + edelay)
+ {
+ /* if we need to fetch more data, do it now */
+ if (ebitoffs == 15)
+ for (p = 1; p < planes; p += 2)
+ {
+ CUSTOM_REG(REG_BPL1DAT + p) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_BPL1PTH + p * 2));
+ CUSTOM_REG_LONG(REG_BPL1PTH + p * 2) += 2;
+ }
+
+ /* now assemble the bits */
+ pfpix0 |= assemble_even_bitplanes(planes, ebitoffs);
+ ebitoffs--;
+
+ /* for high res, assemble a second set of bits */
+ if (hires)
+ {
+ /* reset bit offsets and fetch more data if needed */
+ if (ebitoffs < 0)
+ {
+ ebitoffs = 15;
+
+ for (p = 1; p < planes; p += 2)
+ {
+ CUSTOM_REG(REG_BPL1DAT + p) = amiga_chip_ram_r(CUSTOM_REG_LONG(REG_BPL1PTH + p * 2));
+ CUSTOM_REG_LONG(REG_BPL1PTH + p * 2) += 2;
+ }
+ }
+
+ pfpix1 |= assemble_even_bitplanes(planes, ebitoffs);
+ ebitoffs--;
+ }
+ else
+ pfpix1 |= pfpix0 & 0x2a;
+
+ /* reset bit offsets if needed */
+ if (ebitoffs < 0)
+ ebitoffs = 15;
+ }
+
+ /* compute playfield/sprite collisions for first pixel */
+ collide = pfpix0 ^ CUSTOM_REG(REG_CLXCON);
+ if ((collide & ocolmask) == 0)
+ CUSTOM_REG(REG_CLXDAT) |= (sprpix >> 5) & 0x01e;
+ if ((collide & ecolmask) == 0)
+ CUSTOM_REG(REG_CLXDAT) |= (sprpix >> 1) & 0x1e0;
+ if ((collide & (ecolmask | ocolmask)) == 0)
+ CUSTOM_REG(REG_CLXDAT) |= 0x001;
+
+ /* compute playfield/sprite collisions for second pixel */
+ collide = pfpix1 ^ CUSTOM_REG(REG_CLXCON);
+ if ((collide & ocolmask) == 0)
+ CUSTOM_REG(REG_CLXDAT) |= (sprpix >> 5) & 0x01e;
+ if ((collide & ecolmask) == 0)
+ CUSTOM_REG(REG_CLXDAT) |= (sprpix >> 1) & 0x1e0;
+ if ((collide & (ecolmask | ocolmask)) == 0)
+ CUSTOM_REG(REG_CLXDAT) |= 0x001;
+
+ /* if we are within the display region, render */
+ if (x >= hstart && x < hstop)
+ {
+ /* hold-and-modify mode -- assume low-res (hi-res not supported by the hardware) */
+ if (ham)
+ {
+ /* update the HAM color */
+ pfpix0 = update_ham(pfpix0);
+
+ /* sprite has priority */
+ if (sprpix && pf1pri > (sprpix >> 10))
+ {
+ dst[x*2+0] =
+ dst[x*2+1] = CUSTOM_REG(REG_COLOR00 + (sprpix & 0x1f));
+ }
+
+ /* playfield has priority */
+ else
+ {
+ dst[x*2+0] =
+ dst[x*2+1] = pfpix0;
+ }
+ }
+
+ /* dual playfield mode */
+ else if (dualpf)
+ {
+ int pix;
+
+ /* mask out the sprite if it doesn't have priority */
+ pix = sprpix & 0x1f;
+ if (pix)
+ {
+ if ((pfpix0 & 0x15) && pf1pri <= (sprpix >> 10))
+ pix = 0;
+ if ((pfpix0 & 0x2a) && pf2pri <= (sprpix >> 10))
+ pix = 0;
+ }
+
+ /* write out the left pixel */
+ if (pix)
+ dst[x*2+0] = CUSTOM_REG(REG_COLOR00 + pix);
+ else
+ dst[x*2+0] = CUSTOM_REG(REG_COLOR00 + separate_bitplanes[(CUSTOM_REG(REG_BPLCON2) >> 6) & 1][pfpix0]);
+
+ /* mask out the sprite if it doesn't have priority */
+ pix = sprpix & 0x1f;
+ if (pix)
+ {
+ if ((pfpix1 & 0x15) && pf1pri <= (sprpix >> 10))
+ pix = 0;
+ if ((pfpix1 & 0x2a) && pf2pri <= (sprpix >> 10))
+ pix = 0;
+ }
+
+ /* write out the right pixel */
+ if (pix)
+ dst[x*2+1] = CUSTOM_REG(REG_COLOR00 + pix);
+ else
+ dst[x*2+1] = CUSTOM_REG(REG_COLOR00 + separate_bitplanes[(CUSTOM_REG(REG_BPLCON2) >> 6) & 1][pfpix1]);
+ }
+
+ /* single playfield mode */
+ else
+ {
+ /* sprite has priority */
+ if (sprpix && pf1pri > (sprpix >> 10))
+ {
+ dst[x*2+0] =
+ dst[x*2+1] = CUSTOM_REG(REG_COLOR00 + (sprpix & 0x1f));
+ }
+
+ /* playfield has priority */
+ else
+ {
+ dst[x*2+0] = CUSTOM_REG(REG_COLOR00 + pfpix0);
+ dst[x*2+1] = CUSTOM_REG(REG_COLOR00 + pfpix1);
+ }
+ }
+ }
+ }
+ }
+
+#if 0
+ if ( cpu_getcurrentframe() % 64 == 0 && scanline == 100 )
+ {
+ const char *m_lores = "LORES";
+ const char *m_hires = "HIRES";
+ const char *m_ham = "HAM";
+ const char *m_dualpf = "DUALPF";
+ const char *m_lace = "LACE";
+ const char *m_hilace = "HI-LACE";
+ const char *p = m_lores;
+
+ if ( hires ) p = m_hires;
+ if ( ham ) p = m_ham;
+ if ( dualpf ) p = m_dualpf;
+ if ( lace ) p = m_lace;
+
+ if ( hires && lace ) p = m_hilace;
+
+ popmessage("%s(%d pl od=%04x ed=%04x start=%04x stop=%04x)", p, planes, odelay, edelay, CUSTOM_REG(REG_DDFSTRT), CUSTOM_REG(REG_DDFSTOP) );
+ }
+#endif
+
+ /* end of the line: time to add the modulos */
+ if (scanline >= vstart && scanline < vstop)
+ {
+ int p;
+
+ /* update odd planes */
+ for (p = 0; p < planes; p += 2)
+ CUSTOM_REG_LONG(REG_BPL1PTH + p * 2) += CUSTOM_REG_SIGNED(REG_BPL1MOD);
+
+ /* update even planes */
+ for (p = 1; p < planes; p += 2)
+ CUSTOM_REG_LONG(REG_BPL1PTH + p * 2) += CUSTOM_REG_SIGNED(REG_BPL2MOD);
+ }
+
+ /* restore color00 */
+ CUSTOM_REG(REG_COLOR00) = save_color0;
+
+#if GUESS_COPPER_OFFSET
+ if (cpu_getcurrentframe() % 64 == 0 && scanline == 0)
+ {
+ if (input_code_pressed(KEYCODE_Q))
+ popmessage("%d", wait_offset -= 1);
+ if (input_code_pressed(KEYCODE_W))
+ popmessage("%d", wait_offset += 1);
+ }
+#endif
+}