// license:BSD-3-Clause // copyright-holders:Aaron Giles /*************************************************************************** HAR MadMax hardware **************************************************************************/ #include "emu.h" #include "includes/dcheese.h" /************************************* * * Constants * *************************************/ #define DSTBITMAP_WIDTH 512 #define DSTBITMAP_HEIGHT 512 /************************************* * * Palette translation * *************************************/ PALETTE_INIT_MEMBER(dcheese_state, dcheese) { for (int i = 0; i < 65536; i++) { int data = m_palrom[i]; palette.set_pen_color(i, pal6bit(data >> 0), pal5bit(data >> 6), pal5bit(data >> 11)); } } /************************************* * * Scanline interrupt * *************************************/ void dcheese_state::update_scanline_irq() { /* if not in range, don't bother */ if (m_blitter_vidparam[0x22/2] <= m_blitter_vidparam[0x1e/2]) { int effscan; attotime time; /* compute the effective scanline of the interrupt */ effscan = m_blitter_vidparam[0x22/2] - m_blitter_vidparam[0x1a/2]; if (effscan < 0) effscan += m_blitter_vidparam[0x1e/2]; /* determine the time; if it's in this scanline, bump to the next frame */ time = m_screen->time_until_pos(effscan); if (time < m_screen->scan_period()) time += m_screen->frame_period(); m_blitter_timer->adjust(time); } } void dcheese_state::device_timer(emu_timer &timer, device_timer_id id, int param, void *ptr) { switch (id) { case TIMER_BLITTER_SCANLINE: dcheese_signal_irq(3); update_scanline_irq(); break; case TIMER_SIGNAL_IRQ: dcheese_signal_irq(param); break; default: assert_always(false, "Unknown id in dcheese_state::device_timer"); } } /************************************* * * Video start * *************************************/ void dcheese_state::video_start() { /* the destination bitmap is not directly accessible to the CPU */ m_dstbitmap = std::make_unique(DSTBITMAP_WIDTH, DSTBITMAP_HEIGHT); /* create timers */ m_blitter_timer = timer_alloc(TIMER_BLITTER_SCANLINE); m_signal_irq_timer = timer_alloc(TIMER_SIGNAL_IRQ); /* register for saving */ save_item(NAME(m_blitter_color)); save_item(NAME(m_blitter_xparam)); save_item(NAME(m_blitter_yparam)); save_item(NAME(m_blitter_vidparam)); save_item(NAME(*m_dstbitmap)); } /************************************* * * Video update * *************************************/ uint32_t dcheese_state::screen_update_dcheese(screen_device &screen, bitmap_ind16 &bitmap, const rectangle &cliprect) { int x, y; /* update the pixels */ for (y = cliprect.min_y; y <= cliprect.max_y; y++) { uint16_t *dest = &bitmap.pix16(y); uint16_t *src = &m_dstbitmap->pix16((y + m_blitter_vidparam[0x28/2]) & 0x1ff); for (x = cliprect.min_x; x <= cliprect.max_x; x++) dest[x] = src[x]; } return 0; } /************************************* * * Blitter implementation * *************************************/ void dcheese_state::do_clear( ) { int y; /* clear the requested scanlines */ for (y = m_blitter_vidparam[0x2c/2]; y < m_blitter_vidparam[0x2a/2]; y++) memset(&m_dstbitmap->pix16(y & 0x1ff), 0, DSTBITMAP_WIDTH * 2); /* signal an IRQ when done (timing is just a guess) */ m_signal_irq_timer->adjust(m_screen->scan_period(), 1); } void dcheese_state::do_blit( ) { int32_t const srcminx = m_blitter_xparam[0] << 12; int32_t const srcmaxx = m_blitter_xparam[1] << 12; int32_t const srcminy = m_blitter_yparam[0] << 12; int32_t const srcmaxy = m_blitter_yparam[1] << 12; int32_t const srcx = ((m_blitter_xparam[2] & 0x0fff) | ((m_blitter_xparam[3] & 0x0fff) << 12)) << 7; int32_t const srcy = ((m_blitter_yparam[2] & 0x0fff) | ((m_blitter_yparam[3] & 0x0fff) << 12)) << 7; int32_t const dxdx = (int32_t)(((m_blitter_xparam[4] & 0x0fff) | ((m_blitter_xparam[5] & 0x0fff) << 12)) << 12) >> 12; int32_t const dxdy = (int32_t)(((m_blitter_xparam[6] & 0x0fff) | ((m_blitter_xparam[7] & 0x0fff) << 12)) << 12) >> 12; int32_t const dydx = (int32_t)(((m_blitter_yparam[4] & 0x0fff) | ((m_blitter_yparam[5] & 0x0fff) << 12)) << 12) >> 12; int32_t const dydy = (int32_t)(((m_blitter_yparam[6] & 0x0fff) | ((m_blitter_yparam[7] & 0x0fff) << 12)) << 12) >> 12; uint32_t const pagemask = m_gfxrom.mask() >> 18; int const xstart = m_blitter_xparam[14]; int const xend = m_blitter_xparam[15] + 1; int const ystart = m_blitter_yparam[14]; int const yend = m_blitter_yparam[15]; int const color = (m_blitter_color[0] << 8) & 0xff00; int const mask = (m_blitter_color[0] >> 8) & 0x00ff; int const opaque = (dxdx | dxdy | dydx | dydy) == 0; /* bit of a hack for fredmem */ /* loop over target rows */ for (int y = ystart; y <= yend; y++) { uint16_t *dst = &m_dstbitmap->pix16(y & 0x1ff); /* loop over target columns */ for (int x = xstart; x <= xend; x++) { /* compute current X/Y positions */ int const sx = (srcx + dxdx * (x - xstart) + dxdy * (y - ystart)) & 0xffffff; int const sy = (srcy + dydx * (x - xstart) + dydy * (y - ystart)) & 0xffffff; /* clip to source cliprect */ if (sx >= srcminx && sx <= srcmaxx && sy >= srcminy && sy <= srcmaxy) { /* page comes from bit 22 of Y and bit 21 of X */ int const page = (((sy >> 21) & 2) | ((sx >> 21) & 1) | ((sx >> 20) & 4)) & pagemask; int const pix = m_gfxrom[(page << 18) | (((sy >> 12) & 0x1ff) << 9) | ((sx >> 12) & 0x1ff)]; /* only non-zero pixels get written */ if (pix | opaque) dst[x & 0x1ff] = (pix & mask) | color; } } } /* signal an IRQ when done (timing is just a guess) */ m_signal_irq_timer->adjust(m_screen->scan_period() / 2, 2); /* these extra parameters are written but they are always zero, so I don't know what they do */ if (m_blitter_xparam[8] != 0 || m_blitter_xparam[9] != 0 || m_blitter_xparam[10] != 0 || m_blitter_xparam[11] != 0 || m_blitter_yparam[8] != 0 || m_blitter_yparam[9] != 0 || m_blitter_yparam[10] != 0 || m_blitter_yparam[11] != 0) { logerror("%s:blit! (%04X)\n", machine().describe_context(), m_blitter_color[0]); logerror(" %04X %04X %04X %04X - %04X %04X %04X %04X - %04X %04X %04X %04X - %04X %04X %04X %04X\n", m_blitter_xparam[0], m_blitter_xparam[1], m_blitter_xparam[2], m_blitter_xparam[3], m_blitter_xparam[4], m_blitter_xparam[5], m_blitter_xparam[6], m_blitter_xparam[7], m_blitter_xparam[8], m_blitter_xparam[9], m_blitter_xparam[10], m_blitter_xparam[11], m_blitter_xparam[12], m_blitter_xparam[13], m_blitter_xparam[14], m_blitter_xparam[15]); logerror(" %04X %04X %04X %04X - %04X %04X %04X %04X - %04X %04X %04X %04X - %04X %04X %04X %04X\n", m_blitter_yparam[0], m_blitter_yparam[1], m_blitter_yparam[2], m_blitter_yparam[3], m_blitter_yparam[4], m_blitter_yparam[5], m_blitter_yparam[6], m_blitter_yparam[7], m_blitter_yparam[8], m_blitter_yparam[9], m_blitter_yparam[10], m_blitter_yparam[11], m_blitter_yparam[12], m_blitter_yparam[13], m_blitter_yparam[14], m_blitter_yparam[15]); } } /************************************* * * Blitter read/write * *************************************/ WRITE16_MEMBER(dcheese_state::blitter_color_w) { COMBINE_DATA(&m_blitter_color[offset]); } WRITE16_MEMBER(dcheese_state::blitter_xparam_w) { COMBINE_DATA(&m_blitter_xparam[offset]); } WRITE16_MEMBER(dcheese_state::blitter_yparam_w) { COMBINE_DATA(&m_blitter_yparam[offset]); } WRITE16_MEMBER(dcheese_state::blitter_vidparam_w) { COMBINE_DATA(&m_blitter_vidparam[offset]); switch (offset) { case 0x10/2: /* horiz front porch */ case 0x12/2: /* horiz display start */ case 0x14/2: /* horiz display end */ case 0x16/2: /* horiz back porch */ case 0x18/2: /* vert front porch */ case 0x1a/2: /* vert display start */ case 0x1c/2: /* vert display end */ case 0x1e/2: /* vert back porch */ break; case 0x22/2: /* scanline interrupt */ update_scanline_irq(); break; case 0x24/2: /* writes here after writing to 0x28 */ break; case 0x28/2: /* display starting y */ case 0x2a/2: /* clear end y */ case 0x2c/2: /* clear start y */ break; case 0x38/2: /* blit */ do_blit(); break; case 0x3e/2: /* clear */ do_clear(); break; default: logerror("%06X:write to %06X = %04X & %04x\n", m_maincpu->pc(), 0x2a0000 + 2 * offset, data, mem_mask); break; } } WRITE16_MEMBER(dcheese_state::blitter_unknown_w) { /* written to just before the blitter command register is written */ logerror("%06X:write to %06X = %04X & %04X\n", m_maincpu->pc(), 0x300000 + 2 * offset, data, mem_mask); } READ16_MEMBER(dcheese_state::blitter_vidparam_r) { /* analog inputs seem to be hooked up here -- might not actually map to blitter */ if (offset == 0x02/2) return ioport("2a0002")->read(); if (offset == 0x0e/2) return ioport("2a000e")->read(); /* early code polls on this bit, wants it to be 0 */ if (offset == 0x36/2) return 0xffff ^ (1 << 5); /* log everything else */ logerror("%06X:read from %06X\n", m_maincpu->pc(), 0x2a0000 + 2 * offset); return 0xffff; }