1// Aseprite
2// Copyright (C) 2022 Igara Studio S.A.
3// Copyright (C) 2001-2018 David Capello
4//
5// This program is distributed under the terms of
6// the End-User License Agreement for Aseprite.
7
8#ifdef HAVE_CONFIG_H
9#include "config.h"
10#endif
11
12#include "app/util/freetype_utils.h"
13
14#include "doc/blend_funcs.h"
15#include "doc/blend_internals.h"
16#include "doc/color.h"
17#include "doc/image.h"
18#include "doc/primitives.h"
19#include "ft/algorithm.h"
20#include "ft/face.h"
21#include "ft/hb_shaper.h"
22#include "ft/lib.h"
23
24#include <memory>
25#include <stdexcept>
26
27namespace app {
28
29doc::Image* render_text(const std::string& fontfile, int fontsize,
30 const std::string& text,
31 doc::color_t color,
32 bool antialias)
33{
34 std::unique_ptr<doc::Image> image(nullptr);
35 ft::Lib ft;
36
37 ft::Face face(ft.open(fontfile));
38 if (face.isValid()) {
39 // Set font size
40 face.setSize(fontsize);
41 face.setAntialias(antialias);
42
43 // Calculate text size
44 gfx::Rect bounds = ft::calc_text_bounds(face, text);
45
46 // Render the image and copy it to the clipboard
47 if (!bounds.isEmpty()) {
48 image.reset(doc::Image::create(doc::IMAGE_RGB, bounds.w, bounds.h));
49 doc::clear_image(image.get(), 0);
50
51 ft::ForEachGlyph<ft::Face> feg(face, text);
52 while (feg.next()) {
53 auto glyph = feg.glyph();
54 if (!glyph)
55 continue;
56
57 int t, yimg = - bounds.y + int(glyph->y);
58
59 for (int v=0; v<int(glyph->bitmap->rows); ++v, ++yimg) {
60 const uint8_t* p = glyph->bitmap->buffer + v*glyph->bitmap->pitch;
61 int ximg = - bounds.x + int(glyph->x);
62 int bit = 0;
63
64 for (int u=0; u<int(glyph->bitmap->width); ++u, ++ximg) {
65 int alpha;
66
67 if (antialias) {
68 alpha = *(p++);
69 }
70 else {
71 alpha = ((*p) & (1 << (7 - (bit++))) ? 255: 0);
72 if (bit == 8) {
73 bit = 0;
74 ++p;
75 }
76 }
77
78 int output_alpha = MUL_UN8(doc::rgba_geta(color), alpha, t);
79 if (output_alpha) {
80 doc::color_t output_color =
81 doc::rgba(doc::rgba_getr(color),
82 doc::rgba_getg(color),
83 doc::rgba_getb(color),
84 output_alpha);
85
86 doc::put_pixel(
87 image.get(), ximg, yimg,
88 doc::rgba_blender_normal(
89 doc::get_pixel(image.get(), ximg, yimg),
90 output_color));
91 }
92 }
93 }
94 }
95 }
96 else {
97 throw std::runtime_error("There is no text");
98 }
99 }
100 else {
101 throw std::runtime_error("Error loading font face");
102 }
103
104 return (image ? image.release(): nullptr);
105}
106
107} // namespace app
108