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-rw-r--r--src/devices/video/jangou_blitter.cpp194
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diff --git a/src/devices/video/jangou_blitter.cpp b/src/devices/video/jangou_blitter.cpp
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+// license:BSD-3-Clause
+// copyright-holders:Angelo Salese
+/***************************************************************************
+
+ Jangou Custom Blitter Chip, codename "???" (name scratched afaik)
+
+ device emulation by Angelo Salese, from original jangou.cpp implementation
+ by Angelo Salese, David Haywood and Phil Bennett.
+
+ TODO:
+ - BLTFLIP mechanism;
+ - clean-ups;
+
+***************************************************************************/
+
+#include "emu.h"
+#include "jangou_blitter.h"
+
+
+
+//**************************************************************************
+// GLOBAL VARIABLES
+//**************************************************************************
+
+// device type definition
+const device_type JANGOU_BLITTER = &device_creator<jangou_blitter_device>;
+
+
+//**************************************************************************
+// LIVE DEVICE
+//**************************************************************************
+
+//-------------------------------------------------
+// jangou_blitter_device - constructor
+//-------------------------------------------------
+
+jangou_blitter_device::jangou_blitter_device(const machine_config &mconfig, const char *tag, device_t *owner, UINT32 clock)
+ : device_t(mconfig, JANGOU_BLITTER, "Jangou Blitter Custom Chip", tag, owner, clock, "jangou_blitter", __FILE__)
+{
+}
+
+
+//-------------------------------------------------
+// device_start - device-specific startup
+//-------------------------------------------------
+
+void jangou_blitter_device::device_start()
+{
+ memory_region *devregion = machine().root_device().memregion("gfx");
+ m_gfxrom = devregion->base();
+ if (m_gfxrom == nullptr)
+ fatalerror("JANGOU_BLITTER: \"gfx\" memory base not found");
+ m_gfxrommask = devregion->bytes()-1;
+
+ save_item(NAME(m_pen_data));
+ save_item(NAME(m_blit_data));
+ save_item(NAME(m_blit_buffer));
+}
+
+
+//-------------------------------------------------
+// device_reset - device-specific reset
+//-------------------------------------------------
+
+void jangou_blitter_device::device_reset()
+{
+ memset(m_blit_data, 0, ARRAY_LENGTH(m_blit_data));
+ memset(m_pen_data, 0, ARRAY_LENGTH(m_pen_data));
+ m_bltflip = false;
+}
+
+
+//**************************************************************************
+// READ/WRITE HANDLERS
+//**************************************************************************
+
+// TODO: inline these
+UINT8 jangou_blitter_device::gfx_nibble( UINT32 niboffset )
+{
+ if (niboffset & 1)
+ return (m_gfxrom[(niboffset >> 1) & m_gfxrommask] & 0xf0) >> 4;
+ else
+ return (m_gfxrom[(niboffset >> 1) & m_gfxrommask] & 0x0f);
+}
+
+void jangou_blitter_device::plot_gfx_pixel( UINT8 pix, int x, int y )
+{
+ if (y < 0 || y >= 256)
+ return;
+ if (x < 0 || x >= 256)
+ return;
+
+ if (x & 1)
+ m_blit_buffer[(y * 256) + (x >> 1)] = (m_blit_buffer[(y * 256) + (x >> 1)] & 0x0f) | ((pix << 4) & 0xf0);
+ else
+ m_blit_buffer[(y * 256) + (x >> 1)] = (m_blit_buffer[(y * 256) + (x >> 1)] & 0xf0) | (pix & 0x0f);
+}
+
+WRITE8_MEMBER( jangou_blitter_device::process_w )
+{
+ int src, x, y, h, w, flipx;
+ m_blit_data[offset] = data;
+
+ if (offset == 5)
+ {
+ int count = 0;
+ int xcount, ycount;
+
+ w = (m_blit_data[4] & 0xff) + 1;
+ h = (m_blit_data[5] & 0xff) + 1;
+ src = ((m_blit_data[1] << 8)|(m_blit_data[0] << 0));
+ src |= (m_blit_data[6] & 3) << 16;
+ x = (m_blit_data[2] & 0xff);
+ y = (m_blit_data[3] & 0xff);
+
+ #if 0
+ if(m_bltflip == true)
+ {
+ printf("%02x %02x %02x %02x %02x %02x %02x\n", m_blit_data[0], m_blit_data[1], m_blit_data[2],m_blit_data[3], m_blit_data[4], m_blit_data[5],m_blit_data[6]);
+ printf("=>");
+ for(int i=0;i<0x10;i++)
+ printf("%02x ",m_pen_data[i]);
+ printf("\n");
+ }
+ #endif
+ // lowest bit of src controls flipping / draw direction?
+ flipx = (m_blit_data[0] & 1);
+
+ if (!flipx)
+ src += (w * h) - 1;
+ else
+ src -= (w * h) - 1;
+
+
+ for (ycount = 0; ycount < h; ycount++)
+ {
+ for(xcount = 0; xcount < w; xcount++)
+ {
+ int drawx = (x + xcount) & 0xff;
+ int drawy = (y + ycount) & 0xff;
+ UINT8 dat = gfx_nibble(src + count);
+ UINT8 cur_pen = m_pen_data[dat & 0x0f];
+
+ //dat = cur_pen_lo | (cur_pen_hi << 4);
+
+ if ((cur_pen & 0xff) != 0)
+ plot_gfx_pixel(cur_pen, drawx, drawy);
+
+ if (!flipx)
+ count--;
+ else
+ count++;
+ }
+ }
+
+ //UINT32 new_src = src + count;
+
+ // update source and height after blitter operation
+ // TODO: Jangou doesn't agree with this, later HW?
+ #if 0
+ m_blit_data[0] = new_src & 0xfe;
+ m_blit_data[1] = new_src >> 8;
+ m_blit_data[5] = 0;
+ m_blit_data[6] = new_src >> 16;
+ #endif
+ m_bltflip = false;
+ }
+}
+
+// Sexy Gal swaps around upper src address
+WRITE8_MEMBER( jangou_blitter_device::alt_process_w )
+{
+ const UINT8 translate_addr[7] = { 0, 1, 6, 2, 3, 4, 5 };
+
+ process_w(space,translate_addr[offset],data);
+}
+
+WRITE8_MEMBER( jangou_blitter_device::vregs_w )
+{
+ // bit 5 set by Jangou, left-over?
+ m_pen_data[offset] = data & 0x0f;
+}
+
+WRITE8_MEMBER( jangou_blitter_device::bltflip_w )
+{
+ // TODO: unsure about how this works, Charles says it swaps the nibble but afaik it's used for CPU tiles in Night Gal Summer/Sexy Gal and they seems fine?
+ // Maybe flipx is actually bltflip for later HW?
+ m_bltflip = true;
+}
+
+READ_LINE_MEMBER( jangou_blitter_device::status_r )
+{
+ return false;
+}