OpenTTD Source: src/gfx_layout.cpp Source File

OpenTTD Source 15.0-beta1

gfx_layout.cpp
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1/*
2 * This file is part of OpenTTD.
3 * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
4 * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
5 * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
6 */
7
10#include "stdafx.h"
11#include "core/math_func.hpp"
12#include "gfx_layout.h"
13#include "string_func.h"
14#include "strings_func.h"
15#include "debug.h"
16
17#include "table/control_codes.h"
18
19#include "gfx_layout_fallback.h"
20
21#if defined(WITH_ICU_I18N) && defined(WITH_HARFBUZZ)
22#include "gfx_layout_icu.h"
23#endif /* WITH_ICU_I18N && WITH_HARFBUZZ */
24
25#ifdef WITH_UNISCRIBE
26#include "os/windows/string_uniscribe.h"
27#endif /* WITH_UNISCRIBE */
28
29#ifdef WITH_COCOA
30#include "os/macosx/string_osx.h"
31#endif
32
33#include "safeguards.h"
34
35
37Layouter::LineCache *Layouter::linecache;
38
40Layouter::FontColourMap Layouter::fonts[FS_END];
41
42
48Font::Font(FontSize size, TextColour colour) :
49 fc(FontCache::Get(size)), colour(colour)
50{
51 assert(size < FS_END);
52}
53
63template <typename T>
64 static inline void GetLayouter(Layouter::LineCacheItem &line, std::string_view str, FontState &state)
65{
66 free(line.buffer);
67
68 typename T::CharType *buff_begin = MallocT<typename T::CharType>(str.size() + 1);
69 const typename T::CharType *buffer_last = buff_begin + str.size() + 1;
70 typename T::CharType *buff = buff_begin;
71 FontMap &font_mapping = line.runs;
72 Font *f = Layouter::GetFont(state.fontsize, state.cur_colour);
73
74 line.buffer = buff_begin;
75 font_mapping.clear();
76
77 auto cur = str.begin();
78
79 /*
80 * Go through the whole string while adding Font instances to the font map
81 * whenever the font changes, and convert the wide characters into a format
82 * usable by ParagraphLayout.
83 */
84 for (; buff < buffer_last && cur != str.end();) {
85 char32_t c = Utf8Consume(cur);
86 if (c == '\0' || c == '\n') {
87 /* Caller should already have filtered out these characters. */
88 NOT_REACHED();
89 } else if (c >= SCC_BLUE && c <= SCC_BLACK) {
90 state.SetColour((TextColour)(c - SCC_BLUE));
91 } else if (c == SCC_PUSH_COLOUR) {
92 state.PushColour();
93 } else if (c == SCC_POP_COLOUR) {
94 state.PopColour();
95 } else if (c >= SCC_FIRST_FONT && c <= SCC_LAST_FONT) {
96 state.SetFontSize((FontSize)(c - SCC_FIRST_FONT));
97 } else {
98 /* Filter out non printable characters */
99 if (!IsPrintable(c)) continue;
100 /* Filter out text direction characters that shouldn't be drawn, and
101 * will not be handled in the fallback case because they are mostly
102 * needed for RTL languages which need more proper shaping support. */
103 if (!T::SUPPORTS_RTL && IsTextDirectionChar(c)) continue;
104 buff += T::AppendToBuffer(buff, buffer_last, c);
105 continue;
106 }
107
108 if (font_mapping.empty() || font_mapping.back().first != buff - buff_begin) {
109 font_mapping.emplace_back(buff - buff_begin, f);
110 }
111 f = Layouter::GetFont(state.fontsize, state.cur_colour);
112 }
113
114 /* Better safe than sorry. */
115 *buff = '\0';
116
117 if (font_mapping.empty() || font_mapping.back().first != buff - buff_begin) {
118 font_mapping.emplace_back(buff - buff_begin, f);
119 }
120 line.layout = T::GetParagraphLayout(buff_begin, buff, font_mapping);
121 line.state_after = state;
122}
123
130Layouter::Layouter(std::string_view str, int maxw, FontSize fontsize) : string(str)
131{
132 FontState state(TC_INVALID, fontsize);
133
134 while (true) {
135 auto line_length = str.find_first_of('\n');
136 auto str_line = str.substr(0, line_length);
137
138 LineCacheItem &line = GetCachedParagraphLayout(str_line, state);
139 if (line.layout != nullptr) {
140 state = line.state_after;
141 line.layout->Reflow();
142 } else {
143 /* Line is new, layout it */
144 FontState old_state = state;
145
146#if defined(WITH_ICU_I18N) && defined(WITH_HARFBUZZ)
147 if (line.layout == nullptr) {
148 GetLayouter<ICUParagraphLayoutFactory>(line, str_line, state);
149 if (line.layout == nullptr) {
150 state = old_state;
151 }
152 }
153#endif
154
155#ifdef WITH_UNISCRIBE
156 if (line.layout == nullptr) {
157 GetLayouter<UniscribeParagraphLayoutFactory>(line, str_line, state);
158 if (line.layout == nullptr) {
159 state = old_state;
160 }
161 }
162#endif
163
164#ifdef WITH_COCOA
165 if (line.layout == nullptr) {
166 GetLayouter<CoreTextParagraphLayoutFactory>(line, str_line, state);
167 if (line.layout == nullptr) {
168 state = old_state;
169 }
170 }
171#endif
172
173 if (line.layout == nullptr) {
174 GetLayouter<FallbackParagraphLayoutFactory>(line, str_line, state);
175 }
176 }
177
178 /* Move all lines into a local cache so we can reuse them later on more easily. */
179 for (;;) {
180 auto l = line.layout->NextLine(maxw);
181 if (l == nullptr) break;
182 this->push_back(std::move(l));
183 }
184
185 /* Break out if this was the last line. */
186 if (line_length == std::string_view::npos) {
187 break;
188 }
189
190 /* Go to the next line. */
191 str.remove_prefix(line_length + 1);
192 }
193}
194
199 Dimension Layouter::GetBounds()
200{
201 Dimension d = { 0, 0 };
202 for (const auto &l : *this) {
203 d.width = std::max<uint>(d.width, l->GetWidth());
204 d.height += l->GetLeading();
205 }
206 return d;
207}
208
212 static bool IsConsumedFormattingCode(char32_t ch)
213{
214 if (ch >= SCC_BLUE && ch <= SCC_BLACK) return true;
215 if (ch == SCC_PUSH_COLOUR) return true;
216 if (ch == SCC_POP_COLOUR) return true;
217 if (ch >= SCC_FIRST_FONT && ch <= SCC_LAST_FONT) return true;
218 // All other characters defined in Unicode standard are assumed to be non-consumed.
219 return false;
220}
221
228 ParagraphLayouter::Position Layouter::GetCharPosition(std::string_view::const_iterator ch) const
229{
230 const auto &line = this->front();
231
232 /* Pointer to the end-of-string marker? Return total line width. */
233 if (ch == this->string.end()) {
234 Point p = {_current_text_dir == TD_LTR ? line->GetWidth() : 0, 0};
235 return p;
236 }
237
238 /* Find the code point index which corresponds to the char
239 * pointer into our UTF-8 source string. */
240 size_t index = 0;
241 auto str = this->string.begin();
242 while (str < ch) {
243 char32_t c = Utf8Consume(str);
244 if (!IsConsumedFormattingCode(c)) index += line->GetInternalCharLength(c);
245 }
246
247 /* Initial position, returned if character not found. */
248 const ParagraphLayouter::Position initial_position = Point{_current_text_dir == TD_LTR ? 0 : line->GetWidth(), 0};
249 const ParagraphLayouter::Position *position = &initial_position;
250
251 /* We couldn't find the code point index. */
252 if (str != ch) return *position;
253
254 /* Valid character. */
255
256 /* Scan all runs until we've found our code point index. */
257 size_t best_index = SIZE_MAX;
258 for (int run_index = 0; run_index < line->CountRuns(); run_index++) {
259 const ParagraphLayouter::VisualRun &run = line->GetVisualRun(run_index);
260 const auto &positions = run.GetPositions();
261 const auto &charmap = run.GetGlyphToCharMap();
262
263 auto itp = positions.begin();
264 for (auto it = charmap.begin(); it != charmap.end(); ++it, ++itp) {
265 const size_t cur_index = static_cast<size_t>(*it);
266 /* Found exact character match? */
267 if (cur_index == index) return *itp;
268
269 /* If the character we are looking for has been combined with other characters to form a ligature then
270 * we may not be able to find an exact match. We don't actually know if our character is part of a
271 * ligature. In this case we will aim to select the first character of the ligature instead, so the best
272 * index is the index nearest to but lower than the desired index. */
273 if (cur_index < index && (best_index < cur_index || best_index == SIZE_MAX)) {
274 best_index = cur_index;
275 position = &*itp;
276 }
277 }
278 }
279
280 /* At the end of the run but still didn't find our character so probably a trailing ligature, use the last found position. */
281 return *position;
282}
283
290ptrdiff_t Layouter::GetCharAtPosition(int x, size_t line_index) const
291{
292 if (line_index >= this->size()) return -1;
293
294 const auto &line = this->at(line_index);
295
296 for (int run_index = 0; run_index < line->CountRuns(); run_index++) {
297 const ParagraphLayouter::VisualRun &run = line->GetVisualRun(run_index);
298 const auto &glyphs = run.GetGlyphs();
299 const auto &positions = run.GetPositions();
300 const auto &charmap = run.GetGlyphToCharMap();
301
302 for (int i = 0; i < run.GetGlyphCount(); i++) {
303 /* Not a valid glyph (empty). */
304 if (glyphs[i] == 0xFFFF) continue;
305
306 int begin_x = positions[i].left;
307 int end_x = positions[i].right + 1;
308
309 if (IsInsideMM(x, begin_x, end_x)) {
310 /* Found our glyph, now convert to UTF-8 string index. */
311 size_t index = charmap[i];
312
313 size_t cur_idx = 0;
314 for (auto str = this->string.begin(); str != this->string.end();) {
315 if (cur_idx == index) return str - this->string.begin();
316
317 char32_t c = Utf8Consume(str);
318 if (!IsConsumedFormattingCode(c)) cur_idx += line->GetInternalCharLength(c);
319 }
320 }
321 }
322 }
323
324 return -1;
325}
326
330 Font *Layouter::GetFont(FontSize size, TextColour colour)
331{
332 FontColourMap::iterator it = fonts[size].find(colour);
333 if (it != fonts[size].end()) return it->second.get();
334
335 fonts[size][colour] = std::make_unique<Font>(size, colour);
336 return fonts[size][colour].get();
337}
338
342 void Layouter::Initialize()
343{
344#if defined(WITH_ICU_I18N) && defined(WITH_HARFBUZZ)
345 ICUParagraphLayoutFactory::InitializeLayouter();
346#endif /* WITH_ICU_I18N && WITH_HARFBUZZ */
347}
348
353 void Layouter::ResetFontCache(FontSize size)
354{
355 fonts[size].clear();
356
357 /* We must reset the linecache since it references the just freed fonts */
358 ResetLineCache();
359
360#if defined(WITH_UNISCRIBE)
361 UniscribeResetScriptCache(size);
362#endif
363#if defined(WITH_COCOA)
364 MacOSResetScriptCache(size);
365#endif
366}
367
375 Layouter::LineCacheItem &Layouter::GetCachedParagraphLayout(std::string_view str, const FontState &state)
376{
377 if (linecache == nullptr) {
378 /* Create linecache on first access to avoid trouble with initialisation order of static variables. */
379 linecache = new LineCache();
380 }
381
382 if (auto match = linecache->find(LineCacheQuery{state, str});
383 match != linecache->end()) {
384 return match->second;
385 }
386
387 /* Create missing entry */
388 LineCacheKey key;
389 key.state_before = state;
390 key.str.assign(str);
391 return (*linecache)[std::move(key)];
392}
393
397 void Layouter::ResetLineCache()
398{
399 if (linecache != nullptr) linecache->clear();
400}
401
405 void Layouter::ReduceLineCache()
406{
407 if (linecache != nullptr) {
408 /* TODO LRU cache would be fancy, but not exactly necessary */
409 if (linecache->size() > 4096) ResetLineCache();
410 }
411}
412
421 ParagraphLayouter::Position GetCharPosInString(std::string_view str, const char *ch, FontSize start_fontsize)
422{
423 /* Ensure "ch" is inside "str" or at the exact end. */
424 assert(ch >= str.data() && (ch - str.data()) <= static_cast<ptrdiff_t>(str.size()));
425 auto it_ch = str.begin() + (ch - str.data());
426
427 Layouter layout(str, INT32_MAX, start_fontsize);
428 return layout.GetCharPosition(it_ch);
429}
430
438ptrdiff_t GetCharAtPosition(std::string_view str, int x, FontSize start_fontsize)
439{
440 if (x < 0) return -1;
441
442 Layouter layout(str, INT32_MAX, start_fontsize);
443 return layout.GetCharAtPosition(x, 0);
444}
FontCache
Font cache for basic fonts.
Definition fontcache.h:21
Font
Container with information about a font.
Definition gfx_layout.h:75
Font::Font
Font(FontSize size, TextColour colour)
Construct a new font.
Definition gfx_layout.cpp:48
ICUParagraphLayoutFactory::InitializeLayouter
static void InitializeLayouter()
Initialize data needed for the ICU layouter.
Definition gfx_layout_icu.cpp:385
Layouter
The layouter performs all the layout work.
Definition gfx_layout.h:138
Layouter::Initialize
static void Initialize()
Perform initialization of layout engine.
Definition gfx_layout.cpp:342
Layouter::fonts
static FontColourMap fonts[FS_END]
Cache of Font instances.
Definition gfx_layout.h:186
Layouter::Layouter
Layouter(std::string_view str, int maxw=INT32_MAX, FontSize fontsize=FS_NORMAL)
Create a new layouter.
Definition gfx_layout.cpp:130
Layouter::GetCharAtPosition
ptrdiff_t GetCharAtPosition(int x, size_t line_index) const
Get the character that is at a pixel position in the first line of the layouted text.
Definition gfx_layout.cpp:290
Layouter::ResetFontCache
static void ResetFontCache(FontSize size)
Reset cached font information.
Definition gfx_layout.cpp:353
Layouter::GetCharPosition
ParagraphLayouter::Position GetCharPosition(std::string_view::const_iterator ch) const
Get the position of a character in the layout.
Definition gfx_layout.cpp:228
Layouter::GetFont
static Font * GetFont(FontSize size, TextColour colour)
Get a static font instance.
Definition gfx_layout.cpp:330
Layouter::ResetLineCache
static void ResetLineCache()
Clear line cache.
Definition gfx_layout.cpp:397
Layouter::GetBounds
Dimension GetBounds()
Get the boundaries of this paragraph.
Definition gfx_layout.cpp:199
Layouter::GetCachedParagraphLayout
static LineCacheItem & GetCachedParagraphLayout(std::string_view str, const FontState &state)
Get reference to cache item.
Definition gfx_layout.cpp:375
Layouter::linecache
static LineCache * linecache
Cache of ParagraphLayout lines.
Definition gfx_layout.h:181
Layouter::ReduceLineCache
static void ReduceLineCache()
Reduce the size of linecache if necessary to prevent infinite growth.
Definition gfx_layout.cpp:405
ParagraphLayouter::Position
Position of a glyph within a VisualRun.
Definition gfx_layout.h:94
ParagraphLayouter::VisualRun
Visual run contains data about the bit of text with the same font.
Definition gfx_layout.h:107
control_codes.h
Control codes that are embedded in the translation strings.
debug.h
Functions related to debugging.
IsConsumedFormattingCode
static bool IsConsumedFormattingCode(char32_t ch)
Test whether a character is a non-printable formatting code.
Definition gfx_layout.cpp:212
GetLayouter
static void GetLayouter(Layouter::LineCacheItem &line, std::string_view str, FontState &state)
Helper for getting a ParagraphLayouter of the given type.
Definition gfx_layout.cpp:64
GetCharAtPosition
ptrdiff_t GetCharAtPosition(std::string_view str, int x, FontSize start_fontsize)
Get the character from a string that is drawn at a specific position.
Definition gfx_layout.cpp:438
GetCharPosInString
ParagraphLayouter::Position GetCharPosInString(std::string_view str, const char *ch, FontSize start_fontsize)
Get the leading corner of a character in a single-line string relative to the start of the string.
Definition gfx_layout.cpp:421
gfx_layout.h
Functions related to laying out the texts.
FontMap
std::vector< std::pair< int, Font * > > FontMap
Mapping from index to font.
Definition gfx_layout.h:84
gfx_layout_fallback.h
Functions related to laying out the texts as fallback.
gfx_layout_icu.h
Functions related to laying out the texts with ICU.
FontSize
FontSize
Available font sizes.
Definition gfx_type.h:208
TextColour
TextColour
Colour of the strings, see _string_colourmap in table/string_colours.h or docs/ottd-colourtext-palett...
Definition gfx_type.h:260
math_func.hpp
Integer math functions.
IsInsideMM
constexpr bool IsInsideMM(const T x, const size_t min, const size_t max) noexcept
Checks if a value is in an interval.
Definition math_func.hpp:268
safeguards.h
A number of safeguards to prevent using unsafe methods.
stdafx.h
Definition of base types and functions in a cross-platform compatible way.
free
void free(const void *ptr)
Version of the standard free that accepts const pointers.
Definition stdafx.h:334
string_func.h
Functions related to low-level strings.
IsTextDirectionChar
bool IsTextDirectionChar(char32_t c)
Is the given character a text direction character.
Definition string_func.h:217
MacOSResetScriptCache
void MacOSResetScriptCache(FontSize size)
Delete CoreText font reference for a specific font size.
Definition string_osx.cpp:297
string_osx.h
Functions related to localized text support on OSX.
string_uniscribe.h
Functions related to laying out text on Win32.
_current_text_dir
TextDirection _current_text_dir
Text direction of the currently selected language.
Definition strings.cpp:56
strings_func.h
Functions related to OTTD's strings.
TD_LTR
@ TD_LTR
Text is written left-to-right by default.
Definition strings_type.h:23
Dimension
Dimensions (a width and height) of a rectangle in 2D.
Definition geometry_type.hpp:30
FontState
Text drawing parameters, which can change while drawing a line, but are kept between multiple parts o...
Definition gfx_layout.h:24
FontState::PushColour
void PushColour()
Push the current colour on to the stack.
Definition gfx_layout.h:57
FontState::SetColour
void SetColour(TextColour c)
Switch to new colour c.
Definition gfx_layout.h:37
FontState::PopColour
void PopColour()
Switch to and pop the last saved colour on the stack.
Definition gfx_layout.h:47
FontState::SetFontSize
void SetFontSize(FontSize f)
Switch to using a new font f.
Definition gfx_layout.h:66
FontState::fontsize
FontSize fontsize
Current font size.
Definition gfx_layout.h:25
FontState::cur_colour
TextColour cur_colour
Current text colour.
Definition gfx_layout.h:26
Layouter::LineCacheItem
Item in the linecache.
Definition gfx_layout.h:168
Layouter::LineCacheItem::runs
FontMap runs
Accessed by our ParagraphLayout::nextLine.
Definition gfx_layout.h:171
Layouter::LineCacheItem::buffer
void * buffer
Accessed by our ParagraphLayout::nextLine.
Definition gfx_layout.h:170
Layouter::LineCacheItem::state_after
FontState state_after
Font state after the line.
Definition gfx_layout.h:173
Layouter::LineCacheItem::layout
std::unique_ptr< ParagraphLayouter > layout
Layout of the line.
Definition gfx_layout.h:174
Layouter::LineCacheKey
Key into the linecache.
Definition gfx_layout.h:142
Layouter::LineCacheKey::state_before
FontState state_before
Font state at the beginning of the line.
Definition gfx_layout.h:143
Layouter::LineCacheKey::str
std::string str
Source string of the line (including colour and font size codes).
Definition gfx_layout.h:144
Layouter::LineCacheQuery
Definition gfx_layout.h:147
Point
Coordinates of a point in 2D.
Definition geometry_type.hpp:21