--- /dev/null
+/***************************************************************************
+* Copyright (C) 2010 PCSX4ALL Team *
+* Copyright (C) 2010 Unai *
+* *
+* 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 02111-1307 USA. *
+***************************************************************************/
+
+#ifndef _OP_BLEND_H_
+#define _OP_BLEND_H_
+
+// GPU Blending operations functions
+
+////////////////////////////////////////////////////////////////////////////////
+// Blend bgr555 color in 'uSrc' (foreground) with bgr555 color
+// in 'uDst' (background), returning resulting color.
+//
+// INPUT:
+// 'uSrc','uDst' input: -bbbbbgggggrrrrr
+// ^ bit 16
+// OUTPUT:
+// u16 output: 0bbbbbgggggrrrrr
+// ^ bit 16
+// RETURNS:
+// Where '0' is zero-padding, and '-' is don't care
+////////////////////////////////////////////////////////////////////////////////
+template <int BLENDMODE, bool SKIP_USRC_MSB_MASK>
+GPU_INLINE uint_fast16_t gpuBlendingGeneric(uint_fast16_t uSrc, uint_fast16_t uDst)
+{
+ // These use Blargg's bitwise modulo-clamping:
+ // http://blargg.8bitalley.com/info/rgb_mixing.html
+ // http://blargg.8bitalley.com/info/rgb_clamped_add.html
+ // http://blargg.8bitalley.com/info/rgb_clamped_sub.html
+
+ uint_fast16_t mix;
+
+ // 0.5 x Back + 0.5 x Forward
+ if (BLENDMODE==0) {
+#ifdef GPU_UNAI_USE_ACCURATE_BLENDING
+ // Slower, but more accurate (doesn't lose LSB data)
+ uDst &= 0x7fff;
+ if (!SKIP_USRC_MSB_MASK)
+ uSrc &= 0x7fff;
+ mix = ((uSrc + uDst) - ((uSrc ^ uDst) & 0x0421)) >> 1;
+#else
+ mix = ((uDst & 0x7bde) + (uSrc & 0x7bde)) >> 1;
+#endif
+ }
+
+ // 1.0 x Back + 1.0 x Forward
+ if (BLENDMODE==1) {
+ uDst &= 0x7fff;
+ if (!SKIP_USRC_MSB_MASK)
+ uSrc &= 0x7fff;
+ u32 sum = uSrc + uDst;
+ u32 low_bits = (uSrc ^ uDst) & 0x0421;
+ u32 carries = (sum - low_bits) & 0x8420;
+ u32 modulo = sum - carries;
+ u32 clamp = carries - (carries >> 5);
+ mix = modulo | clamp;
+ }
+
+ // 1.0 x Back - 1.0 x Forward
+ if (BLENDMODE==2) {
+ uDst &= 0x7fff;
+ if (!SKIP_USRC_MSB_MASK)
+ uSrc &= 0x7fff;
+ u32 diff = uDst - uSrc + 0x8420;
+ u32 low_bits = (uDst ^ uSrc) & 0x8420;
+ u32 borrows = (diff - low_bits) & 0x8420;
+ u32 modulo = diff - borrows;
+ u32 clamp = borrows - (borrows >> 5);
+ mix = modulo & clamp;
+ }
+
+ // 1.0 x Back + 0.25 x Forward
+ if (BLENDMODE==3) {
+ uDst &= 0x7fff;
+ uSrc = ((uSrc >> 2) & 0x1ce7);
+ u32 sum = uSrc + uDst;
+ u32 low_bits = (uSrc ^ uDst) & 0x0421;
+ u32 carries = (sum - low_bits) & 0x8420;
+ u32 modulo = sum - carries;
+ u32 clamp = carries - (carries >> 5);
+ mix = modulo | clamp;
+ }
+
+ return mix;
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+// Convert bgr555 color in uSrc to padded u32 5.4:5.4:5.4 bgr fixed-pt
+// color triplet suitable for use with HQ 24-bit quantization.
+//
+// INPUT:
+// 'uDst' input: -bbbbbgggggrrrrr
+// ^ bit 16
+// RETURNS:
+// u32 output: 000bbbbbXXXX0gggggXXXX0rrrrrXXXX
+// ^ bit 31
+// Where 'X' are fixed-pt bits, '0' is zero-padding, and '-' is don't care
+////////////////////////////////////////////////////////////////////////////////
+GPU_INLINE u32 gpuGetRGB24(uint_fast16_t uSrc)
+{
+ return ((uSrc & 0x7C00)<<14)
+ | ((uSrc & 0x03E0)<< 9)
+ | ((uSrc & 0x001F)<< 4);
+}
+
+
+////////////////////////////////////////////////////////////////////////////////
+// Blend padded u32 5.4:5.4:5.4 bgr fixed-pt color triplet in 'uSrc24'
+// (foreground color) with bgr555 color in 'uDst' (background color),
+// returning the resulting u32 5.4:5.4:5.4 color.
+//
+// INPUT:
+// 'uSrc24' input: 000bbbbbXXXX0gggggXXXX0rrrrrXXXX
+// ^ bit 31
+// 'uDst' input: -bbbbbgggggrrrrr
+// ^ bit 16
+// RETURNS:
+// u32 output: 000bbbbbXXXX0gggggXXXX0rrrrrXXXX
+// ^ bit 31
+// Where 'X' are fixed-pt bits, '0' is zero-padding, and '-' is don't care
+////////////////////////////////////////////////////////////////////////////////
+template <int BLENDMODE>
+GPU_INLINE u32 gpuBlending24(u32 uSrc24, uint_fast16_t uDst)
+{
+ // These use techniques adapted from Blargg's techniques mentioned in
+ // in gpuBlending() comments above. Not as much bitwise trickery is
+ // necessary because of presence of 0 padding in uSrc24 format.
+
+ u32 uDst24 = gpuGetRGB24(uDst);
+ u32 mix;
+
+ // 0.5 x Back + 0.5 x Forward
+ if (BLENDMODE==0) {
+ const u32 uMsk = 0x1FE7F9FE;
+ // Only need to mask LSBs of uSrc24, uDst24's LSBs are 0 already
+ mix = (uDst24 + (uSrc24 & uMsk)) >> 1;
+ }
+
+ // 1.0 x Back + 1.0 x Forward
+ if (BLENDMODE==1) {
+ u32 sum = uSrc24 + uDst24;
+ u32 carries = sum & 0x20080200;
+ u32 modulo = sum - carries;
+ u32 clamp = carries - (carries >> 9);
+ mix = modulo | clamp;
+ }
+
+ // 1.0 x Back - 1.0 x Forward
+ if (BLENDMODE==2) {
+ // Insert ones in 0-padded borrow slot of color to be subtracted from
+ uDst24 |= 0x20080200;
+ u32 diff = uDst24 - uSrc24;
+ u32 borrows = diff & 0x20080200;
+ u32 clamp = borrows - (borrows >> 9);
+ mix = diff & clamp;
+ }
+
+ // 1.0 x Back + 0.25 x Forward
+ if (BLENDMODE==3) {
+ uSrc24 = (uSrc24 & 0x1FC7F1FC) >> 2;
+ u32 sum = uSrc24 + uDst24;
+ u32 carries = sum & 0x20080200;
+ u32 modulo = sum - carries;
+ u32 clamp = carries - (carries >> 9);
+ mix = modulo | clamp;
+ }
+
+ return mix;
+}
+
+#endif //_OP_BLEND_H_
notaz.gp2x.de / pcsx_rearmed.git / blobdiff