Minetest  5.4.0
imagefilters.h
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1 /*
2 Copyright (C) 2015 Aaron Suen <warr1024@gmail.com>
3 
4 This program is free software; you can redistribute it and/or modify
5 it under the terms of the GNU Lesser General Public License as published by
6 the Free Software Foundation; either version 2.1 of the License, or
7 (at your option) any later version.
8 
9 This program is distributed in the hope that it will be useful,
10 but WITHOUT ANY WARRANTY; without even the implied warranty of
11 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
12 GNU Lesser General Public License for more details.
13 
14 You should have received a copy of the GNU Lesser General Public License along
15 with this program; if not, write to the Free Software Foundation, Inc.,
16 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
17 */
18 
19 #pragma once
20 
22 
23 /* Fill in RGB values for transparent pixels, to correct for odd colors
24  * appearing at borders when blending. This is because many PNG optimizers
25  * like to discard RGB values of transparent pixels, but when blending then
26  * with non-transparent neighbors, their RGB values will shpw up nonetheless.
27  *
28  * This function modifies the original image in-place.
29  *
30  * Parameter "threshold" is the alpha level below which pixels are considered
31  * transparent. Should be 127 for 3d where alpha is threshold, but 0 for
32  * 2d where alpha is blended.
33  */
34 void imageCleanTransparent(video::IImage *src, u32 threshold);
35 
36 /* Scale a region of an image into another image, using nearest-neighbor with
37  * anti-aliasing; treat pixels as crisp rectangles, but blend them at boundaries
38  * to prevent non-integer scaling ratio artifacts. Note that this may cause
39  * some blending at the edges where pixels don't line up perfectly, but this
40  * filter is designed to produce the most accurate results for both upscaling
41  * and downscaling.
42  */
43 void imageScaleNNAA(video::IImage *src, const core::rect<s32> &srcrect, video::IImage *dest);
void imageCleanTransparent(video::IImage *src, u32 threshold)
Definition: imagefilters.cpp:34
void imageScaleNNAA(video::IImage *src, const core::rect< s32 > &srcrect, video::IImage *dest)
Definition: imagefilters.cpp:88