22726e4d |
1 | /****************************************************************************** |
2 | * Arachnoid Graphics Plugin for Mupen64Plus |
3 | * http://bitbucket.org/wahrhaft/mupen64plus-video-arachnoid/ |
4 | * |
5 | * Copyright (C) 2007 Kristofer Karlsson, Rickard Niklasson |
6 | * |
7 | * This program is free software; you can redistribute it and/or |
8 | * modify it under the terms of the GNU General Public License |
9 | * as published by the Free Software Foundation; either version 2 |
10 | * of the License, or (at your option) any later version. |
11 | * |
12 | * This program is distributed in the hope that it will be useful, |
13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
15 | * GNU General Public License for more details. |
16 | * |
17 | * You should have received a copy of the GNU General Public License |
18 | * along with this program; if not, write to the Free Software |
19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
20 | *****************************************************************************/ |
21 | |
22 | //***************************************************************************** |
23 | // |
24 | // NOTE THAT THIS FILE IS BASED ON MATERIAL FROM glN64. |
25 | // http://gln64.emulation64.com/ |
26 | // |
27 | //***************************************************************************** |
28 | |
29 | #include "CombinerStageCreator.h" |
30 | |
31 | //----------------------------------------------------------------------------- |
32 | //* Set Stage |
33 | //! Function used to set combiner stage, tries to simplify and optimize as |
34 | //! much as possible. |
35 | //! From glN64 |
36 | //! @param[in] combineCycle Values to be added/subracted/multiplied and interpolated. |
37 | //! @param[out] stageOut Simplified combine cycle with combiner formula. |
38 | //----------------------------------------------------------------------------- |
39 | void setStage(CombineCycle* combineCycle, CombinerStage* stageOut) |
40 | { |
41 | // Load the first operand |
42 | stageOut->op[0].op = LOAD; |
43 | stageOut->op[0].param1 = combineCycle->loadValue; |
44 | stageOut->numOps = 1; |
45 | |
46 | // If we're just subtracting zero, skip it |
47 | if (combineCycle->subValue != ZERO) |
48 | { |
49 | if (combineCycle->subValue == stageOut->op[0].param1) |
50 | stageOut->op[0].param1 = ZERO; |
51 | else |
52 | { |
53 | //Subract operation |
54 | stageOut->op[1].op = SUB; |
55 | stageOut->op[1].param1 = combineCycle->subValue; |
56 | stageOut->numOps++; |
57 | } |
58 | } |
59 | |
60 | //Multiply operation |
61 | if ((stageOut->numOps > 1) || (stageOut->op[0].param1 != ZERO)) |
62 | { |
63 | if (combineCycle->multValue == ZERO) |
64 | { |
65 | stageOut->numOps = 1; |
66 | stageOut->op[0].op = LOAD; |
67 | stageOut->op[0].param1 = ZERO; |
68 | } |
69 | else |
70 | { |
71 | if ( stageOut->numOps == 1 && stageOut->op[0].param1 == ONE ) |
72 | { |
73 | //LOAD |
74 | stageOut->op[0].param1 = combineCycle->multValue; |
75 | } |
76 | else |
77 | { |
78 | //MULT |
79 | stageOut->op[stageOut->numOps].op = MUL; |
80 | stageOut->op[stageOut->numOps].param1 = combineCycle->multValue; |
81 | stageOut->numOps++; |
82 | } |
83 | } |
84 | } |
85 | |
86 | //Don't bother adding zero |
87 | if (combineCycle->addValue != ZERO) |
88 | { |
89 | // If all we have so far is zero, then load this instead |
90 | if ((stageOut->numOps == 1) && (stageOut->op[0].param1 == ZERO)) |
91 | { |
92 | stageOut->op[0].param1 = combineCycle->addValue; |
93 | } |
94 | else |
95 | { |
96 | stageOut->op[stageOut->numOps].op = ADD; |
97 | stageOut->op[stageOut->numOps].param1 = combineCycle->addValue; |
98 | stageOut->numOps++; |
99 | } |
100 | } |
101 | |
102 | // Handle interpolation |
103 | if ((stageOut->numOps == 4) && (stageOut->op[1].param1 == stageOut->op[3].param1)) |
104 | { |
105 | stageOut->numOps = 1; |
106 | stageOut->op[0].op = INTERPOLATE; |
107 | stageOut->op[0].param2 = stageOut->op[1].param1; |
108 | stageOut->op[0].param3 = stageOut->op[2].param1; |
109 | } |
110 | } |