1 /* divide.cpp
2  * Copyright (C) 2006 Jean-Sebastien Senecal (js@drone.ws)
3  * This file is a Frei0r plugin.
4  * The code is a modified version of code from the Gimp.
5  *
6  * This program is free software; you can redistribute it and/or modify
7  * it under the terms of the GNU General Public License as published by
8  * the Free Software Foundation; either version 2 of the License, or
9  * (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful,
12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
14  * GNU General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
19  */
20 
21 #include "frei0r.hpp"
22 #include "frei0r_math.h"
23 
24 #define NBYTES 4
25 #define ALPHA 3
26 
27 class divide : public frei0r::mixer2
28 {
29 public:
divide(unsigned int width,unsigned int height)30   divide(unsigned int width, unsigned int height)
31   {
32   }
33 
34   /**
35    *
36    * Perform an RGB[A] divide operation between the pixel sources in1
37    * and in2.  in1 is the numerator, in2 the denominator.
38    *
39    **/
update(double time,uint32_t * out,const uint32_t * in1,const uint32_t * in2)40   void update(double time,
41               uint32_t* out,
42               const uint32_t* in1,
43               const uint32_t* in2)
44   {
45     const uint8_t *src1 = reinterpret_cast<const uint8_t*>(in1);
46     const uint8_t *src2 = reinterpret_cast<const uint8_t*>(in2);
47     uint8_t *dst = reinterpret_cast<uint8_t*>(out);
48     uint32_t sizeCounter = size;
49 
50     uint32_t b, result;
51 
52     while (sizeCounter--)
53       {
54         for (b = 0; b < ALPHA; b++)
55           {
56             result = ((src1[b] * 256) / (1 + src2[b]));
57             dst[b] = MIN(result, 255u);
58           }
59 
60         dst[ALPHA] = MIN(src1[ALPHA], src2[ALPHA]);
61 
62         src1 += NBYTES;
63         src2 += NBYTES;
64         dst += NBYTES;
65       }
66   }
67 
68 
69 
70 };
71 
72 
73 frei0r::construct<divide> plugin("divide",
74                                  "Perform an RGB[A] divide operation between the pixel sources: input1 is the numerator, input2 the denominator",
75                                  "Jean-Sebastien Senecal",
76                                  0,2,
77                                  F0R_COLOR_MODEL_RGBA8888);
78 
79