2 SDL - Simple DirectMedia Layer
3 Copyright (C) 1997-2009 Sam Lantinga
5 This library is free software; you can redistribute it and/or
6 modify it under the terms of the GNU Lesser General Public
7 License as published by the Free Software Foundation; either
8 version 2.1 of the License, or (at your option) any later version.
10 This library is distributed in the hope that it will be useful,
11 but WITHOUT ANY WARRANTY; without even the implied warranty of
12 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 Lesser General Public License for more details.
15 You should have received a copy of the GNU Lesser General Public
16 License along with this library; if not, write to the Free Software
17 Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
24 Chunky to planar conversion routine
25 1 byte/pixel -> 4 or 8 bit planes
32 .globl _SDL_Atari_C2pConvert
33 .globl _SDL_Atari_C2pConvert8
34 .globl _SDL_Atari_C2pConvert4
35 .globl _SDL_Atari_C2pConvert4_pal
37 /* ------------ Conversion C2P, 8 bits ------------ */
40 _SDL_Atari_C2pConvert8:
41 movel sp@(4),c2p_source
43 movel sp@(12),c2p_width
44 movel sp@(16),c2p_height
45 movel sp@(20),c2p_dblligne
46 movel sp@(24),c2p_srcpitch
47 movel sp@(28),c2p_dstpitch
49 moveml d2-d7/a2-a6,sp@-
51 movel c2p_source,c2p_cursrc
52 movel c2p_dest,c2p_curdst
56 movew c2p_height+2,c2p_row
61 SDL_Atari_C2p8_rowloop:
74 d0 = a7a6a5a4a3a2a1a0 b7b6b5b4b3b2b1b0 c7c6c5c4c3c2c1c0 d7d6d5d4d3d2d1d0
75 d1 = e7e6e5e4e3e2e1e0 f7f6f5f4f3f2f1f0 g7g6g5g4g3g2g1g0 h7h6h5h4h3h2h1h0
76 d2 = i7i6i5i4i3i2i1i0 j7j6j5j4j3j2j1j0 k7k6k5k4k3k2k1k0 l7l6l5l4l3l2l1l0
77 d3 = m7m6m5m4m3m2m1m0 n7n6n5n4n3n2n1n0 o7o6o5o4o3o2o1o0 p7p6p5p4p3p2p1p0
111 d0 = a7a6a5a4e7e6e5e4 i7i6i5i4m7m6m5m4 c7c6c5c4g7g6g5g4 k7k6k5k4o7o6o5o4
112 d1 = a3a2a1a0e3e2e1e0 i3i2i1i0m3m2m1m0 c3c2c1c0g3g2g1g0 k3k2k1k0o3o2o1o0
113 d2 = b7b6b5b4f7f6f5f4 j7j6j5j4n7n6n5n4 d7d6d5d4h7h6h5h4 l7l6l5l4p7p6p5p4
114 d3 = b3b2b1b0f3f2f1f0 j3j2j1j0n3n2n1n0 d3d2d1d0h3h2h1h0 l3l2l1l0p3p2p1p0
116 bras SDL_Atari_C2p8_start
118 SDL_Atari_C2p8_pix16:
125 d0 = a7a6a5a4a3a2a1a0 b7b6b5b4b3b2b1b0 c7c6c5c4c3c2c1c0 d7d6d5d4d3d2d1d0
126 d1 = e7e6e5e4e3e2e1e0 f7f6f5f4f3f2f1f0 g7g6g5g4g3g2g1g0 h7h6h5h4h3h2h1h0
127 d2 = i7i6i5i4i3i2i1i0 j7j6j5j4j3j2j1j0 k7k6k5k4k3k2k1k0 l7l6l5l4l3l2l1l0
128 d3 = m7m6m5m4m3m2m1m0 n7n6n5n4n3n2n1n0 o7o6o5o4o3o2o1o0 p7p6p5p4p3p2p1p0
166 d0 = a7a6a5a4e7e6e5e4 i7i6i5i4m7m6m5m4 c7c6c5c4g7g6g5g4 k7k6k5k4o7o6o5o4
167 d1 = a3a2a1a0e3e2e1e0 i3i2i1i0m3m2m1m0 c3c2c1c0g3g2g1g0 k3k2k1k0o3o2o1o0
168 d2 = b7b6b5b4f7f6f5f4 j7j6j5j4n7n6n5n4 d7d6d5d4h7h6h5h4 l7l6l5l4p7p6p5p4
169 d3 = b3b2b1b0f3f2f1f0 j3j2j1j0n3n2n1n0 d3d2d1d0h3h2h1h0 l3l2l1l0p3p2p1p0
172 SDL_Atari_C2p8_start:
190 d0 = a7b7a5b5e7f7e5f5 i7j7i5j5m7n7m5n5 c7d7c5d5g7h7g5h5 k7l7k5l5o7p7o5p5
191 d1 = a3b3a1b1e3f3e1f1 i3j3i1j1m3n3m1n1 c3d3c1d1g3h3g1h1 k3l3k1l1o3p3o1p1
192 d2 = a6b6a4b4e6f6e4f4 i6j6i4j4m6n6m4n4 c6d6c4d4g6h6g4h4 k6l6k4l4o6p6o4p4
193 d3 = a2b2a0b0e2f2e0f0 i2j2i0j0m2n2m0n0 c2d2c0d0g2h2g0h0 k2l2k0l0o2p2o0p0
207 d0 = a7b7a5b5e7f7e5f5 i7j7i5j5m7n7m5n5 a6b6a4b4e6f6e4f4 i6j6i4j4m6n6m4n4
208 d1 = a3b3a1b1e3f3e1f1 i3j3i1j1m3n3m1n1 a2b2a0b0e2f2e0f0 i2j2i0j0m2n2m0n0
209 d2 = c7d7c5d5g7h7g5h5 k7l7k5l5o7p7o5p5 c6d6c4d4g6h6g4h4 k6l6k4l4o6p6o4p4
210 d3 = c3d3c1d1g3h3g1h1 k3l3k1l1o3p3o1p1 c2d2c0d0g2h2g0h0 k2l2k0l0o2p2o0p0
228 d0 = a7b7c7d7e7f7g7h7 i7j7k7l7m7n7o7p7 a6b6c6d6e6f6g6h6 i6j6k6l6m6n6o6p6
229 d1 = a3b3c3d3e3f3g3h3 i3j3k3l3m3n3o3p3 a2b2c2d2e2f2g2h2 i2j2k2l2m2n2o2p2
230 d2 = a5b5c5d5e5f5g5h5 i5j5k5l5m5n5o5p5 a4b4c4d4e4f4g4h4 i4j4k4l4m4n4o4p4
231 d3 = a1b1c1d1e1f1g1h1 i1j1k1l1m1n1o1p1 a0b0c0d0e0f0g0h0 i0j0k0l0m0n0o0p0
244 bgt SDL_Atari_C2p8_pix16
251 /* Double the line ? */
253 movel c2p_srcpitch,d0
254 movel c2p_dstpitch,d1
257 beqs SDL_Atari_C2p8_nodblline
266 SDL_Atari_C2p8_dblloop:
271 dbra d7,SDL_Atari_C2p8_dblloop
275 SDL_Atari_C2p8_nodblline:
283 bne SDL_Atari_C2p8_rowloop
285 moveml sp@+,d2-d7/a2-a6
288 /* ------------ Conversion C2P, 4 bits ------------ */
290 _SDL_Atari_C2pConvert4:
291 movel sp@(4),c2p_source
292 movel sp@(8),c2p_dest
293 movel sp@(12),c2p_width
294 movel sp@(16),c2p_height
295 movel sp@(20),c2p_dblligne
296 movel sp@(24),c2p_srcpitch
297 movel sp@(28),c2p_dstpitch
299 moveml d2-d7/a2-a6,sp@-
303 lea _SDL_Atari_table_c2p,a2
305 #if defined(__M68020__)
312 movel a0,a4 | Save start address of source
313 movel a1,a5 | Save start address of dest
326 #if defined(__M68020__)
348 #if defined(__M68020__)
372 movel a5,a6 | src line
373 movel a5,a1 | dest line
395 moveml sp@+,d2-d7/a2-a6
398 /* ------------ Conversion of a light palette in 4 bits ------------ */
400 _SDL_Atari_C2pConvert4_pal:
401 /* a0 is a 256-word light palette */
406 lea _SDL_Atari_table_c2p,a1
420 dbra d1,c2p_pal_initbyte
423 dbra d3,c2p_pal_initbcl
429 /* ------------ Buffers ------------ */
434 .comm _SDL_Atari_C2pConvert,4
435 .comm _SDL_Atari_table_c2p,1024
437 .comm c2p_source,4 /* Source framebuffer */
438 .comm c2p_dest,4 /* Destination framebuffer */
439 .comm c2p_width,4 /* Width of zone to convert */
440 .comm c2p_height,4 /* Height of zone to convert */
441 .comm c2p_dblligne,4 /* Double the lines while converting ? */
442 .comm c2p_srcpitch,4 /* Source pitch */
443 .comm c2p_dstpitch,4 /* Destination pitch */
444 .comm c2p_cursrc,4 /* Current source line */
445 .comm c2p_curdst,4 /* Current destination line */
446 .comm c2p_rowlen,2 /* Line length in bytes */
447 .comm c2p_row,2 /* Current line number */