BizHawk/waterbox/pcfx/king-bgfast.inc

271 lines
7.6 KiB
C++

/******************************************************************************/
/* Mednafen NEC PC-FX Emulation Module */
/******************************************************************************/
/* king-bgfast.inc:
** Copyright (C) 2006-2016 Mednafen Team
**
** This program is free software; you can redistribute it and/or
** modify it under the terms of the GNU General Public License
** as published by the Free Software Foundation; either version 2
** of the License, or (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program; if not, write to the Free Software Foundation, Inc.,
** 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
*/
// Loop prefix non-endless
#define DRAWBG8x1_LPRE() if(bat_x < bat_width) {
// Loop postfix non-endless
#define DRAWBG8x1_LPOST() } bat_x = (bat_x + 1) & bat_width_mask;
#define CDBG_REASON(format, ...)
//printf("BG%d Reason: " format "\n", n, ## __VA_ARGS__);
static bool CanDrawBG_Fast(int n)
{
static const int cg_per_mode[0x8] =
{
0, // Invalid mode
1, // 2-bit mode
2, // 4-bit mode
4, // 8-bit mode
8, // 16-bit mode
8, // 16-bit mode
8, // 16-bit mode
8, // 16-bit mode
};
const unsigned int bgmode = (king->bgmode >> (n * 4)) & 0xF;
const uint32 bat_offset = king->BGBATAddr[n] * 1024;
const uint32 cg_offset = king->BGCGAddr[n] * 1024;
const uint32 bg_width = (king->BGSize[n] & 0xF0) >> 4;
const uint32 bg_height = king->BGSize[n] & 0x0F;
// If the bgmode is 0, or 6/7(EXT DOT modes), abort.
if(!(bgmode & 0x7) || ((bgmode & 0x7) >= 6))
{
CDBG_REASON("Mode %02x out of range", bgmode);
return(FALSE);
}
// BG width out of range?
if(bg_width < 0x3 || bg_width > 0xA)
{
CDBG_REASON("Width %02x out of range", bg_width);
return(FALSE);
}
// BG height out of range?
if(bg_height < 0x3 || bg_height > 0xA)
{
CDBG_REASON("Height %02x out of range", bg_height);
return(FALSE);
}
// Time for very stringent checks for BG0! Don't draw if the sub-screen is a different size than the main screen,
// or the subscreen CG base != the main screen CG base, or the subscreen BAT base != main screen BAT base(when bgmode & 0x8 is TRUE)
if(!n)
{
if(king->priority & 0x1000)
{
CDBG_REASON("Affine transform enabled");
return(FALSE);
}
if((king->BGSize[0] & 0xFF) != (king->BGSize[0] >> 8))
{
CDBG_REASON("Main Screen/Sub Screen Size Mismatch");
return(FALSE);
}
// Since we already made sure the main screen/sub screen sizes match, we only
// care if BG base or CG base don't match if endless/repeat scrolling is enabled.
// Otherwise, the subscreen won't show at all.
if(king->BGScrollMode & 0x1)
{
if(king->BGCGAddr[0] != king->BG0SubCGAddr)
{
CDBG_REASON("Main Screen/Sub Screen CG base mismatch");
return(FALSE);
}
if(bgmode & 0x8)
{
if(king->BGBATAddr[0] != king->BG0SubBATAddr)
{
CDBG_REASON("Main Screen/Sub Screen BAT base mismatch");
return(FALSE);
}
}
}
}
// If microprogram fetching is disabled, abort.
if(!(king->MPROGControl & 0x1))
{
CDBG_REASON("Microprogram disabled");
return(FALSE);
}
else
{
int remap_thing = 0;
bool bat_fetch = FALSE;
for(int x = 0; x < 16; x++)
{
uint16 mpd;
// Forcing CG and BAT to 0 if the affine bit != rotate_mode is not technically correct.
// If there is a mismatch, it's more likely the effective CG and BAT address for the pixel/segment
// being drawn won't be calculated correctly, likely being just the initial offsets.
mpd = king->MPROGData[x];
// Fetching for this BG number?
if(((mpd >> 6) & 0x3) != n)
continue;
// NOP
if(mpd & 0x100)
continue;
// Affine bit.
if(mpd & 0x20)
{
CDBG_REASON("Affine bit set");
return(FALSE);
}
// BAT fetch
if(mpd & 0x10)
{
if(((bat_offset & 0x20000) >> 14) != (x & 8))
{
CDBG_REASON("BAT MPROG/base bank mismatch");
return(FALSE);
}
bat_fetch = TRUE;
}
else // CG fetch:
{
// CG offset/bank mismatch...
if(((cg_offset & 0x20000) >> 14) != (x & 8))
{
CDBG_REASON("CG MPROG/base bank mismatch");
return(FALSE);
}
// Mismatch between CG fetch type and BG mode!
if((mpd & 0x8) != (bgmode & 0x8))
{
CDBG_REASON("Mismatch between CG fetch type and bg mode");
return(FALSE);
}
// Skewed CG fetch order
if((mpd & 0x7) != remap_thing)
{
CDBG_REASON("Skewed CG fetch order");
return(FALSE);
}
remap_thing++;
}
}
// CG fetch count mismatch
if(remap_thing != cg_per_mode[bgmode & 0x7])
{
CDBG_REASON("CG fetch count mismatch");
return(FALSE);
}
// BG mode demands a BAT fetch, but we don't have one!
if((bgmode & 0x8) && !bat_fetch)
{
CDBG_REASON("Missing BAT fetch");
return(FALSE);
}
}
return(TRUE);
}
static void DrawBG_Fast(uint32 *target, int n)
{
const uint16 bgmode = (king->bgmode >> (n * 4)) & 0xF;
const bool endless = (king->BGScrollMode >> n) & 0x1;
const uint32 XScroll = sign_x_to_s32((n ? 10 : 11), king->BGXScroll[n]);
const uint32 YScroll = sign_x_to_s32((n ? 10 : 11), king->BGYScroll[n]);
const uint32 bat_offset = king->BGBATAddr[n] * 1024;
const uint32 cg_offset = king->BGCGAddr[n] * 1024;
const uint32 bat_and_cg_page = (king->PageSetting & 0x0010) ? 1 : 0;
const uint32 YOffset = (YScroll + (fx_vce.raster_counter - 22)) & 0xFFFF;
const uint32 layer_or = (LAYER_BG0 + n) << 28;
const int ysmall = YOffset & 0x7;
const unsigned int bat_width_shift = (king->BGSize[n] & 0xF0) >> 4;
const unsigned int bat_width = (1 << bat_width_shift) >> 3;
const unsigned int bat_width_mask = endless ? (bat_width - 1) : ((((1 << 0xA) * 2) / 8) - 1);
const int bat_height_shift = king->BGSize[n] & 0x0F;
const int bat_height = (1 << bat_height_shift) >> 3;
const int bat_height_mask = endless ? (bat_height - 1) : ((((1 << 0xA) * 2) / 8) - 1);
// We don't need to &= cg_offset and bat_offset with 0x1ffff after here, as the effective addresses
// calculated with them are anded with 0x1ffff in the rendering code already.
const uint16 * const king_cg_base = &king->KRAM[bat_and_cg_page][cg_offset & 0x20000];
const uint16 * const king_bat_base = &king->KRAM[bat_and_cg_page][bat_offset & 0x20000];
int bat_y = (YOffset >> 3) & bat_height_mask;
uint32 bat_x = (XScroll >> 3) & bat_width_mask;
target += 8 - (XScroll & 0x7);
// If we're in non-endless scroll mode, and we've scrolled past our visible area in the vertical direction, so return.
if(!endless && bat_y >= bat_height) // Draw this line as transparency and return?
{
return;
}
// Adjust/corrupt bat_y to be faster in our blitting code
bat_y = (bat_y << bat_width_shift) >> 3;
const uint32 palette_offset = ((vce_rendercache.palette_offset[1 + (n >> 1)] >> ((n & 1) ? 8 : 0)) << 1) & 0x1FF;
const uint32 * const palette_ptr = &vce_rendercache.palette_table_cache[palette_offset];
{
int wmul = (1 << bat_width_shift), wmask = (1 << bat_height_shift) - 1;
int sexy_y_pos = (YOffset & wmask) * wmul;
#if 0
#define BGFAST_BATMODE (bgmode & 0x8)
#include "king-bgfast-blit.inc"
#else
if(bgmode & 0x8)
{
#define BGFAST_BATMODE 1
#include "king-bgfast-blit.inc"
#undef BGFAST_BATMODE
}
else
{
#define BGFAST_BATMODE 0
#include "king-bgfast-blit.inc"
#undef BGFAST_BATMODE
}
#endif
}
}