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Diffstat (limited to 'trunk/src/emu/video/k053250.c')
-rw-r--r-- | trunk/src/emu/video/k053250.c | 469 |
1 files changed, 469 insertions, 0 deletions
diff --git a/trunk/src/emu/video/k053250.c b/trunk/src/emu/video/k053250.c new file mode 100644 index 00000000000..b5f86814ace --- /dev/null +++ b/trunk/src/emu/video/k053250.c @@ -0,0 +1,469 @@ +#include "k053250.h" + +const device_type K053250 = &device_creator<k053250_t>; + +k053250_t::k053250_t(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock) + : device_t(mconfig, K053250, "K053250", tag, owner, clock) +{ +} + +void k053250_t::static_set_screen_tag(device_t &device, const char *screen_tag) +{ + k053250_t &dev = downcast<k053250_t &>(device); + dev.screen_tag = screen_tag; +} + +void k053250_t::static_set_offsets(device_t &device, int offx, int offy) +{ + k053250_t &dev = downcast<k053250_t &>(device); + dev.offx = offx; + dev.offy = offy; +} + +void k053250_t::unpack_nibbles() +{ + if(!m_region) + throw emu_fatalerror("k053250 %s: no associated region found\n", tag()); + + const UINT8 *base = m_region->base(); + int size = m_region->bytes(); + unpacked = auto_alloc_array(machine(), UINT8, size*2); + for(int i=0; i<size; i++) { + unpacked[2*i] = base[i] >> 4; + unpacked[2*i+1] = base[i] & 15; + } + unpacked_size = 2*size; +} + +void k053250_t::device_start() +{ + screen = machine().device<screen_device>(screen_tag); + ram = auto_alloc_array_clear(machine(), UINT16, 0x6000/2); + buffer[0] = ram + 0x2000; + buffer[1] = ram + 0x2800; + + unpack_nibbles(); + + save_pointer(NAME(ram), 0x6000/2); + save_item(NAME(regs)); + save_item(NAME(page)); + save_item(NAME(frame)); +} + +void k053250_t::device_reset() +{ + page = 0; + frame = -1; + memset(regs, 0, sizeof(regs)); +} + +// utility function to render a clipped scanline vertically or horizontally +inline void k053250_t::pdraw_scanline32(bitmap_rgb32 &bitmap, const pen_t *palette, UINT8 *source, + const rectangle &cliprect, int linepos, int scroll, int zoom, + UINT32 clipmask, UINT32 wrapmask, UINT32 orientation, bitmap_ind8 &priority, UINT8 pri) +{ +// a sixteen-bit fixed point resolution should be adequate to our application +#define FIXPOINT_PRECISION 16 +#define FIXPOINT_PRECISION_HALF (1<<(FIXPOINT_PRECISION-1)) + + int end_pixel, flip, dst_min, dst_max, dst_start, dst_length; + + UINT32 src_wrapmask; + UINT8 *src_base; + int src_fx, src_fdx; + int pix_data, dst_offset; + const pen_t *pal_base; + UINT8 *pri_base; + UINT32 *dst_base; + int dst_adv; + + // flip X and flip Y also switch role when the X Y coordinates are swapped + if (!(orientation & ORIENTATION_SWAP_XY)) + { + flip = orientation & ORIENTATION_FLIP_X; + dst_min = cliprect.min_x; + dst_max = cliprect.max_x; + } + else + { + flip = orientation & ORIENTATION_FLIP_Y; + dst_min = cliprect.min_y; + dst_max = cliprect.max_y; + } + + if (clipmask) + { + // reject scanlines that are outside of the target bitmap's right(bottom) clip boundary + dst_start = -scroll; + if (dst_start > dst_max) return; + + // calculate target length + dst_length = clipmask + 1; + if (zoom) dst_length = (dst_length << 6) / zoom; + + // reject scanlines that are outside of the target bitmap's left(top) clip boundary + end_pixel = dst_start + dst_length - 1; + if (end_pixel < dst_min) return; + + // clip scanline tail + if ((end_pixel -= dst_max) > 0) dst_length -= end_pixel; + + // reject zero-length scanlines + if (dst_length <= 0) return; + + // calculate zoom factor + src_fdx = zoom << (FIXPOINT_PRECISION-6); + + // clip scanline head + end_pixel = dst_min; + if ((end_pixel -= dst_start) > 0) + { + // chop scanline to the correct length and move target start location to the left(top) clip boundary + dst_length -= end_pixel; + dst_start = dst_min; + + // and skip the source for the left(top) clip region + src_fx = end_pixel * src_fdx + FIXPOINT_PRECISION_HALF; + } + else + // the point five bias is to ensure even distribution of stretched or shrinked pixels + src_fx = FIXPOINT_PRECISION_HALF; + + // adjust flipped source + if (flip) + { + // start from the target's clipped end if the scanline is flipped + dst_start = dst_max + dst_min - dst_start - (dst_length-1); + + // and move source start location to the opposite end + src_fx += (dst_length-1) * src_fdx - 1; + src_fdx = -src_fdx; + } + } + else + { + // draw wrapped scanline at virtual bitmap boundary when source clipping is off + dst_start = dst_min; + dst_length = dst_max - dst_min + 1; // target scanline spans the entire visible area + src_fdx = zoom << (FIXPOINT_PRECISION-6); + + // pre-advance source for the clipped region + if (!flip) + src_fx = (scroll + dst_min) * src_fdx + FIXPOINT_PRECISION_HALF; + else + { + src_fx = (scroll + dst_max) * src_fdx + FIXPOINT_PRECISION_HALF-1; + src_fdx = -src_fdx; + } + } + + if (!(orientation & ORIENTATION_SWAP_XY)) + { + // calculate target increment for horizontal scanlines which is exactly one + dst_adv = 1; + dst_offset = dst_length; + pri_base = &priority.pix8(linepos, dst_start + dst_offset); + dst_base = &bitmap.pix32(linepos, dst_start + dst_length); + } + else + { + // calculate target increment for vertical scanlines which is the bitmap's pitch value + dst_adv = bitmap.rowpixels(); + dst_offset= dst_length * dst_adv; + pri_base = &priority.pix8(dst_start, linepos + dst_offset); + dst_base = &bitmap.pix32(dst_start, linepos + dst_offset); + } + + // generalized + src_base = source; + + // there is no need to wrap source offsets along with source clipping + // so we set all bits of the wrapmask to one + src_wrapmask = (clipmask) ? ~0 : wrapmask; + + pal_base = palette; + dst_offset = -dst_offset; // negate target offset in order to terminated draw loop at zero condition + + if (pri) + { + // draw scanline and update priority bitmap + do + { + pix_data = src_base[(src_fx>>FIXPOINT_PRECISION) & src_wrapmask]; + src_fx += src_fdx; + + if (pix_data) + { + pix_data = pal_base[pix_data]; + pri_base[dst_offset] = pri; + dst_base[dst_offset] = pix_data; + } + } + while (dst_offset += dst_adv); + } + else + { + // draw scanline but do not update priority bitmap + do + { + pix_data = src_base[(src_fx>>FIXPOINT_PRECISION) & src_wrapmask]; + src_fx += src_fdx; + + if (pix_data) + { + dst_base[dst_offset] = pal_base[pix_data]; + } + } + while (dst_offset += dst_adv); + } + +#undef FIXPOINT_PRECISION +#undef FIXPOINT_PRECISION_HALF +} + +void k053250_t::draw( bitmap_rgb32 &bitmap, const rectangle &cliprect, int colorbase, int flags, int priority ) +{ + UINT8 *pix_ptr; + const pen_t *pal_base, *pal_ptr; + UINT32 src_clipmask, src_wrapmask, dst_wrapmask; + int linedata_offs, line_pos, line_start, line_end, scroll_corr; + int color, offset, zoom, scroll, passes, i; + bool wrap500 = false; + + UINT16 *line_ram = buffer[page]; // pointer to physical line RAM + int map_scrollx = short(regs[0] << 8 | regs[1]) - offx; // signed horizontal scroll value + int map_scrolly = short(regs[2] << 8 | regs[3]) - offy; // signed vertical scroll value + UINT8 ctrl = regs[4]; // register four is the main control register + + // copy visible boundary values to more accessible locations + int dst_minx = cliprect.min_x; + int dst_maxx = cliprect.max_x; + int dst_miny = cliprect.min_y; + int dst_maxy = cliprect.max_y; + + int orientation = 0; // orientation defaults to no swapping and no flipping + int dst_height = 512; // virtual bitmap height defaults to five hundred and twelve pixels + int linedata_adv = 4; // line info packets are four words(eight bytes) apart + + // switch X and Y parameters when the first bit of the control register is cleared + if (!(ctrl & 0x01)) orientation |= ORIENTATION_SWAP_XY; + + // invert X parameters when the forth bit of the control register is set + if (ctrl & 0x08) orientation |= ORIENTATION_FLIP_X; + + // invert Y parameters when the fifth bit of the control register is set + if (ctrl & 0x10) orientation |= ORIENTATION_FLIP_Y; + + switch (ctrl >> 5) // the upper four bits of the control register select source and target dimensions + { + case 0 : + // Xexex: L6 galaxies + // Metam: L4 forest, L5 arena, L6 tower interior, final boss + + // crop source offset between zero and two hundred and fifty-five inclusive, + // and set virtual bitmap height to two hundred and fifty-six pixels + src_wrapmask = src_clipmask = 0xff; + dst_height = 0x100; + break; + case 1 : + // Xexex: prologue, L7 nebulae + + // the source offset is cropped to zero and five hundred and eleven inclusive + src_wrapmask = src_clipmask = 0x1ff; + break; + case 4 : + // Xexex: L1 sky and boss, L3 planet, L5 poly-face, L7 battle ship patches + // Metam: L1 summoning circle, L3 caves, L6 gargoyle towers + + // crop source offset between zero and two hundred and fifty-five inclusive, + // and allow source offset to wrap back at 500 hexadecimal to minus 300 hexadecimal + src_wrapmask = src_clipmask = 0xff; + wrap500 = true; + break; +// case 2 : // Xexex: title +// case 7 : // Xexex: L4 organic stage + default: + // crop source offset between zero and one thousand and eleven inclusive, + // keep other dimensions to their defaults + src_wrapmask = src_clipmask = 0x3ff; + break; + } + + // disable source clipping when the third bit of the control register is set + if (ctrl & 0x04) src_clipmask = 0; + + if (!(orientation & ORIENTATION_SWAP_XY)) // normal orientaion with no X Y switching + { + line_start = dst_miny; // the first scanline starts at the minimum Y clip location + line_end = dst_maxy; // the last scanline ends at the maximum Y clip location + scroll_corr = map_scrollx; // concentrate global X scroll + linedata_offs = map_scrolly; // determine where to get info for the first line + + if (orientation & ORIENTATION_FLIP_X) + { + scroll_corr = -scroll_corr; // X scroll adjustment should be negated in X flipped scenarioes + } + + if (orientation & ORIENTATION_FLIP_Y) + { + linedata_adv = -linedata_adv; // traverse line RAM backward in Y flipped scenarioes + linedata_offs += bitmap.height() - 1; // and get info for the first line from the bottom + } + + dst_wrapmask = ~0; // scanlines don't seem to wrap horizontally in normal orientation + passes = 1; // draw scanline in a single pass + } + else // orientaion with X and Y parameters switched + { + line_start = dst_minx; // the first scanline starts at the minimum X clip location + line_end = dst_maxx; // the last scanline ends at the maximum X clip location + scroll_corr = map_scrolly; // concentrate global Y scroll + linedata_offs = map_scrollx; // determine where to get info for the first line + + if (orientation & ORIENTATION_FLIP_Y) + { + scroll_corr = 0x100 - scroll_corr; // apply common vertical correction + + // Y correction (ref: 1st and 5th boss) + scroll_corr -= 2; // apply unique vertical correction + + // X correction (ref: 1st boss, seems to undo non-rotated global X offset) + linedata_offs -= 5; // apply unique horizontal correction + } + + if (orientation & ORIENTATION_FLIP_X) + { + linedata_adv = -linedata_adv; // traverse line RAM backward in X flipped scenarioes + linedata_offs += bitmap.width() - 1; // and get info for the first line from the bottom + } + + if (src_clipmask) + { + // determine target wrap boundary and draw scanline in two passes if the source is clipped + dst_wrapmask = dst_height - 1; + passes = 2; + } + else + { + // otherwise disable target wraparound and draw scanline in a single pass + dst_wrapmask = ~0; + passes = 1; + } + } + + linedata_offs *= 4; // each line info packet has four words(eight bytes) + linedata_offs &= 0x7ff; // and it should wrap at the four-kilobyte boundary + linedata_offs += line_start * linedata_adv; // pre-advance line info offset for the clipped region + + // load physical palette base + pal_base = machine().pens + (colorbase << 4) % machine().total_colors(); + + // walk the target bitmap within the visible area vertically or horizontally, one line at a time + for (line_pos=line_start; line_pos <= line_end; linedata_offs += linedata_adv, line_pos++) + { + linedata_offs &= 0x7ff; // line info data wraps at the four-kilobyte boundary + + color = line_ram[linedata_offs]; // get scanline color code + if (color == 0xffff) continue; // reject scanline if color code equals minus one + + offset = line_ram[linedata_offs + 1]; // get first pixel offset in ROM + if (!(color & 0xff) && !offset) continue; // reject scanline if both color and pixel offset are zero + + // calculate physical palette location + // there can be thirty-two color codes and each code represents sixteen pens + pal_ptr = pal_base + ((color & 0x1f) << 4); + + // calculate physical pixel location + // each offset unit represents two hundred and fifty six pixels and should wrap at ROM boundary for safety + pix_ptr = unpacked + ((offset << 8) % unpacked_size); + + // get scanline zoom factor + // For example, 0x20 doubles the length, 0x40 maintains a one-to-one length, + // and 0x80 halves the length. The zoom center is at the beginning of the + // scanline therefore it is not necessary to adjust render start position + zoom = line_ram[linedata_offs + 2]; + + scroll = (short)line_ram[linedata_offs + 3]; // get signed local scroll value for the current scanline + + // scavenged from old code; improves Xexex' first level sky + if (wrap500 && scroll >= 0x500) scroll -= 0x800; + + scroll += scroll_corr; // apply final scroll correction + scroll &= dst_wrapmask; // wraparound scroll value if necessary + + // draw scanlines wrapped at virtual bitmap boundary in two passes + // this should not impose too much overhead due to clipping performed by the render code + i = passes; + do + { + /* + Parameter descriptions: + + bitmap : pointer to a MAME bitmap as the render target + pal_ptr : pointer to the palette's physical location relative to the scanline + pix_ptr : pointer to the physical start location of source pixels in ROM + cliprect : pointer to a rectangle structue which describes the visible area of the target bitmap + line_pos : scanline render position relative to the target bitmap + should be a Y offset to the target bitmap in normal orientaion, + or an X offset to the target bitmap if X,Y are swapped + scroll : source scroll value of the scanline + zoom : source zoom factor of the scanline + src_clipmask : source offset clip mask; source pixels with offsets beyond the scope of this mask will not be drawn + src_wrapmask : source offset wrap mask; wraps source offset around, no effect when src_clipmask is set + orientation : flags indicating whether scanlines should be drawn horizontally, vertically, forward or backward + priority : value to be written to the priority bitmap, no effect when equals zero + */ + pdraw_scanline32(bitmap, pal_ptr, pix_ptr, cliprect, + line_pos, scroll, zoom, src_clipmask, src_wrapmask, orientation, machine().priority_bitmap, (UINT8)priority); + + // shift scanline position one virtual screen upward to render the wrapped end if necessary + scroll -= dst_height; + } + while (--i); + } +} + +void k053250_t::dma(int limiter) +{ + int current_frame = screen->frame_number(); + + if (limiter && current_frame == frame) + return; // make sure we only do DMA transfer once per frame + + frame = current_frame; + memcpy(buffer[page], ram, 0x1000); + page ^= 1; +} + +READ16_MEMBER(k053250_t::reg_r) +{ + return regs[offset]; +} + +WRITE16_MEMBER(k053250_t::reg_w) +{ + if (ACCESSING_BITS_0_7) + { + // start LVC DMA transfer at the falling edge of control register's bit1 + if (offset == 4 && !(data & 2) && (regs[4] & 2)) + dma(1); + + regs[offset] = data; + } +} + +READ16_MEMBER(k053250_t::ram_r) +{ + return ram[offset]; +} + +WRITE16_MEMBER(k053250_t::ram_w) +{ + COMBINE_DATA(ram+offset); +} + +READ16_MEMBER(k053250_t::rom_r) +{ + return m_region->base()[0x80000 * regs[6] + 0x800 * regs[7] + offset/2]; +} + |