pflow.c revision c73f511526464f8e56c242df80552e9b0d94ae3d 
1/*
2 *
3 * (C) Copyright IBM Corp. 1998-2007 - All Rights Reserved
4 *
5 */
6
7#include "unicode/utypes.h"
8#include "unicode/uchar.h"
9#include "unicode/ubidi.h"
10#include "unicode/ustring.h"
11
12#include "layout/LETypes.h"
13
14#include "layout/loengine.h"
15#include "layout/playout.h"
16#include "layout/plruns.h"
17
18#include "pflow.h"
19
20#include "arraymem.h"
21#include "ucreader.h"
22
23/*
24 * Move the line below out of this comment
25 * to add a locale run to the pl_paragraphs
26 * that are created.
27#define TEST_LOCALE "zh_TW"
28 */
29
30#define MARGIN 10
31#define LINE_GROW 32
32#define PARA_GROW 8
33
34#define CH_LF 0x000A
35#define CH_CR 0x000D
36#define CH_LSEP 0x2028
37#define CH_PSEP 0x2029
38
39struct pf_object
40{
41    pl_paragraph    **fParagraphLayout;
42
43    le_int32          fParagraphCount;
44    le_int32          fParagraphMax;
45    le_int32          fParagraphGrow;
46
47    le_int32          fLineCount;
48    le_int32          fLinesMax;
49    le_int32          fLinesGrow;
50
51    pl_line         **fLines;
52
53   LEUnicode         *fChars;
54
55    le_int32          fLineHeight;
56    le_int32          fAscent;
57    le_int32          fWidth;
58    le_int32          fHeight;
59    UBiDiLevel        fParagraphLevel;
60};
61
62typedef struct pf_object pf_object;
63
64
65static LEUnicode *skipLineEnd(LEUnicode *ptr)
66{
67    if (ptr[0] == CH_CR && ptr[1] == CH_LF) {
68        ptr += 1;
69    }
70
71    return ptr + 1;
72}
73
74static le_int32 findFontRun(const pl_fontRuns *fontRuns, le_int32 offset)
75{
76    le_int32 runCount = pl_getFontRunCount(fontRuns);
77    le_int32 run;
78
79    for (run = 0; run < runCount; run += 1) {
80        if (pl_getFontRunLimit(fontRuns, run) > offset) {
81            return run;
82        }
83    }
84
85    return -1;
86}
87
88static void subsetFontRuns(const pl_fontRuns *fontRuns, le_int32 start, le_int32 limit, pl_fontRuns *sub)
89{
90    le_int32 startRun = findFontRun(fontRuns, start);
91    le_int32 endRun   = findFontRun(fontRuns, limit - 1);
92    le_int32 run;
93
94    pl_resetFontRuns(sub);
95
96    for (run = startRun; run <= endRun; run += 1) {
97        const le_font *runFont = pl_getFontRunFont(fontRuns, run);
98        le_int32 runLimit = pl_getFontRunLimit(fontRuns, run) - start;
99
100        if (run == endRun) {
101            runLimit = limit - start;
102        }
103
104        pl_addFontRun(sub, runFont, runLimit);
105    }
106}
107
108pf_flow *pf_create(const LEUnicode chars[], le_int32 charCount, const pl_fontRuns *fontRuns, LEErrorCode *status)
109{
110    pf_object *flow;
111    le_int32 ascent  = 0;
112    le_int32 descent = 0;
113    le_int32 leading = 0;
114	pl_localeRuns *locales = NULL;
115    pl_fontRuns *fr;
116    LEUnicode *pStart;
117    static const LEUnicode separators[] = {CH_LF, CH_CR, CH_LSEP, CH_PSEP, 0x0000};
118
119	if (LE_FAILURE(*status)) {
120		return NULL;
121	}
122
123    flow = NEW_ARRAY(pf_object, 1);
124
125    flow->fParagraphLayout = NULL;
126    flow->fParagraphCount  = 0;
127    flow->fParagraphMax    = PARA_GROW;
128    flow->fParagraphGrow   = PARA_GROW;
129    flow->fLineCount       = 0;
130    flow->fLinesMax        = LINE_GROW;
131    flow->fLinesGrow       = LINE_GROW;
132    flow->fLines           = NULL;
133    flow->fChars           = NULL;
134    flow->fLineHeight      = -1;
135    flow->fAscent          = -1;
136    flow->fWidth           = -1;
137    flow->fHeight          = -1;
138    flow->fParagraphLevel  = UBIDI_DEFAULT_LTR;
139
140    fr = pl_openEmptyFontRuns(0);
141
142#ifdef TEST_LOCALE
143    locales = pl_openEmptyLocaleRuns(0);
144#endif
145
146    flow->fLines = NEW_ARRAY(pl_line *, flow->fLinesMax);
147    flow->fParagraphLayout = NEW_ARRAY(pl_paragraph *, flow->fParagraphMax);
148
149    flow->fChars = NEW_ARRAY(LEUnicode, charCount + 1);
150    LE_ARRAY_COPY(flow->fChars, chars, charCount);
151    flow->fChars[charCount] = 0;
152
153    pStart = &flow->fChars[0];
154
155    while (*pStart != 0) {
156        LEUnicode *pEnd = u_strpbrk(pStart, separators);
157        le_int32 pAscent, pDescent, pLeading;
158        pl_paragraph *paragraphLayout = NULL;
159
160        if (pEnd == NULL) {
161            pEnd = &flow->fChars[charCount];
162        }
163
164        if (pEnd != pStart) {
165            subsetFontRuns(fontRuns, pStart - flow->fChars, pEnd - flow->fChars, fr);
166
167#ifdef TEST_LOCALE
168            pl_resetLocaleRuns(locales);
169            pl_addLocaleRun(locales, TEST_LOCALE, pEnd - pStart);
170#endif
171
172            paragraphLayout = pl_create(pStart, pEnd - pStart, fr, NULL, NULL, locales, flow->fParagraphLevel, FALSE, status);
173
174            if (LE_FAILURE(*status)) {
175                break; /* return? something else? */
176            }
177
178            if (flow->fParagraphLevel == UBIDI_DEFAULT_LTR) {
179                flow->fParagraphLevel = pl_getParagraphLevel(paragraphLayout);
180            }
181
182            pAscent  = pl_getAscent(paragraphLayout);
183            pDescent = pl_getDescent(paragraphLayout);
184            pLeading = pl_getLeading(paragraphLayout);
185
186            if (pAscent > ascent) {
187                ascent = pAscent;
188            }
189
190            if (pDescent > descent) {
191                descent = pDescent;
192            }
193
194            if (pLeading > leading) {
195                leading = pLeading;
196            }
197        }
198
199        if (flow->fParagraphCount >= flow->fParagraphMax) {
200            flow->fParagraphLayout = (pl_paragraph **) GROW_ARRAY(flow->fParagraphLayout, flow->fParagraphMax + flow->fParagraphGrow);
201            flow->fParagraphMax += flow->fParagraphGrow;
202        }
203
204        flow->fParagraphLayout[flow->fParagraphCount++] = paragraphLayout;
205
206        if (*pEnd == 0) {
207            break;
208        }
209
210        pStart = skipLineEnd(pEnd);
211    }
212
213    flow->fLineHeight = ascent + descent + leading;
214    flow->fAscent     = ascent;
215
216    pl_closeLocaleRuns(locales);
217    pl_closeFontRuns(fr);
218
219    return (pf_flow *) flow;
220}
221
222void pf_close(pf_flow *flow)
223{
224    pf_object *obj = (pf_object *) flow;
225    le_int32 i;
226
227    for (i = 0; i < obj->fLineCount; i += 1) {
228        DELETE_ARRAY(obj->fLines[i]);
229    }
230
231    DELETE_ARRAY(obj->fLines);
232
233    for (i = 0; i < obj->fParagraphCount; i += 1) {
234        pl_close(obj->fParagraphLayout[i]);
235    }
236
237    DELETE_ARRAY(obj->fParagraphLayout);
238
239    DELETE_ARRAY(obj->fChars);
240
241    DELETE_ARRAY(obj);
242}
243
244
245le_int32 pf_getAscent(pf_flow *flow)
246{
247    pf_object *obj = (pf_object *) flow;
248
249    return obj->fAscent;
250}
251
252le_int32 pf_getLineHeight(pf_flow *flow)
253{
254    pf_object *obj = (pf_object *) flow;
255
256    return obj->fLineHeight;
257}
258
259le_int32 pf_getLineCount(pf_flow *flow)
260{
261    pf_object *obj = (pf_object *) flow;
262
263    return obj->fLineCount;
264}
265
266static void addLine(pf_object *obj, pl_line *line)
267{
268    if (obj->fLineCount >= obj->fLinesMax) {
269        obj->fLines = (pl_line **) GROW_ARRAY(obj->fLines, obj->fLinesMax + obj->fLinesGrow);
270        obj->fLinesMax += obj->fLinesGrow;
271    }
272
273    obj->fLines[obj->fLineCount++] = line;
274}
275
276void pf_breakLines(pf_flow *flow, le_int32 width, le_int32 height)
277{
278    pf_object *obj = (pf_object *) flow;
279    le_int32 li, p;
280    float lineWidth;
281    pl_line *line;
282
283    obj->fHeight = height;
284
285    /* don't re-break if the width hasn't changed */
286    if (obj->fWidth == width) {
287        return;
288    }
289
290    obj->fWidth  = width;
291
292    lineWidth = (float) (width - 2 * MARGIN);
293
294    /* Free the old Lines... */
295    for (li = 0; li < obj->fLineCount; li += 1) {
296        pl_closeLine(obj->fLines[li]);
297    }
298
299    obj->fLineCount = 0;
300
301    for (p = 0; p < obj->fParagraphCount; p += 1) {
302        pl_paragraph *paragraphLayout = obj->fParagraphLayout[p];
303
304        if (paragraphLayout != NULL) {
305            pl_reflow(paragraphLayout);
306            while ((line = pl_nextLine(paragraphLayout, lineWidth)) != NULL) {
307                addLine(obj, line);
308            }
309        } else {
310            addLine(obj, NULL);
311        }
312    }
313}
314
315void pf_draw(pf_flow *flow, rs_surface *surface, le_int32 firstLine, le_int32 lastLine)
316{
317    pf_object *obj = (pf_object *) flow;
318    le_int32 li, x, y;
319
320    x = MARGIN;
321    y = obj->fAscent;
322
323    for (li = firstLine; li <= lastLine; li += 1) {
324        const pl_line *line = obj->fLines[li];
325
326        if (line != NULL) {
327            le_int32 runCount = pl_countLineRuns(line);
328            le_int32 run;
329
330		    if (obj->fParagraphLevel == UBIDI_RTL) {
331			    le_int32 lastX = pl_getLineWidth(line);
332
333			    x = (obj->fWidth - lastX - MARGIN);
334		    }
335
336
337            for (run = 0; run < runCount; run += 1) {
338                const pl_visualRun *visualRun = pl_getLineVisualRun(line, run);
339                le_int32 glyphCount = pl_getVisualRunGlyphCount(visualRun);
340                const le_font *font = pl_getVisualRunFont(visualRun);
341                const LEGlyphID *glyphs = pl_getVisualRunGlyphs(visualRun);
342                const float *positions = pl_getVisualRunPositions(visualRun);
343
344                rs_drawGlyphs(surface, font, glyphs, glyphCount, positions, x, y, obj->fWidth, obj->fHeight);
345            }
346        }
347
348        y += obj->fLineHeight;
349    }
350}
351
352pf_flow *pf_factory(const char *fileName, const le_font *font, gs_guiSupport *guiSupport)
353{
354    LEErrorCode status  = LE_NO_ERROR;
355    le_int32 charCount;
356    const UChar *text = uc_readFile(fileName, guiSupport, &charCount);
357    pl_fontRuns *fontRuns;
358    pf_flow *result = NULL;
359
360    if (text == NULL) {
361        return NULL;
362    }
363
364    fontRuns = pl_openEmptyFontRuns(0);
365
366    pl_addFontRun(fontRuns, font, charCount);
367
368    result = pf_create(text, charCount, fontRuns, &status);
369
370	if (LE_FAILURE(status)) {
371		pf_close(result);
372		result = NULL;
373	}
374
375    pl_closeFontRuns(fontRuns);
376
377    DELETE_ARRAY(text);
378
379    return result;
380}
381
382