dlangui.graphics.images source code

1 // Written in the D programming language.
2 
3 /**
4 This module contains image loading functions.
5 
6 Currently uses FreeImage.
7 
8 Usage of libpng is not feasible under linux due to conflicts of library and binding versions.
9 
10 Synopsis:
11 
12 ----
13 import dlangui.graphics.images;
14 
15 ----
16 
17 Copyright: Vadim Lopatin, 2014
18 License:   Boost License 1.0
19 Authors:   Vadim Lopatin, coolreader.org@gmail.com
20 */
21 module dlangui.graphics.images;
22 
23 public import dlangui.core.config;
24 static if (BACKEND_GUI):
25 
26 import arsd.image;
27 
28 import dlangui.core.logger;
29 import dlangui.core.types;
30 import dlangui.graphics.colors;
31 import dlangui.graphics.drawbuf;
32 import dlangui.core.streams;
33 import std.path;
34 import std.conv : to;
35 
36 
37 /// load and decode image from file to ColorDrawBuf, returns null if loading or decoding is failed
38 ColorDrawBuf loadImage(string filename) {
39     static import std.file;
40     try {
41         immutable ubyte[] data = cast(immutable ubyte[])std.file.read(filename);
42         return loadImage(data, filename);
43     } catch (Exception e) {
44         Log.e("exception while loading image from file ", filename);
45         Log.e(to!string(e));
46         return null;
47     }
48 }
49 
50 /// load and decode image from input stream to ColorDrawBuf, returns null if loading or decoding is failed
51 ColorDrawBuf loadImage(immutable ubyte[] data, string filename) {
52     Log.d("Loading image from file " ~ filename);
53 
54     import std.algorithm : endsWith;
55     if (filename.endsWith(".xpm")) {
56         import dlangui.graphics.xpm.reader : parseXPM;
57         try {
58             return parseXPM(data);
59         }
60         catch(Exception e) {
61             Log.e("Failed to load image from file ", filename);
62             Log.e(to!string(e));
63             return null;
64         }
65     }
66 
67     auto image = loadImageFromMemory(data);
68     ColorDrawBuf buf = new ColorDrawBuf(image.width, image.height);
69     for(int j = 0; j < buf.height; j++)
70     {
71         auto scanLine = buf.scanLine(j);
72         for(int i = 0; i < buf.width; i++)
73         {
74             auto color = image.getPixel(i, j);
75             scanLine[i] = makeRGBA(color.r, color.g, color.b, 255 - color.a);
76         }
77     }
78     return buf;
79 }