diff options
Diffstat (limited to 'source/html')
| -rw-r--r-- | source/html/html-layout.c | 195 |
1 files changed, 195 insertions, 0 deletions
diff --git a/source/html/html-layout.c b/source/html/html-layout.c index ad3dd621..5bfcac85 100644 --- a/source/html/html-layout.c +++ b/source/html/html-layout.c @@ -116,6 +116,33 @@ static void add_flow_image(fz_context *ctx, fz_pool *pool, fz_html *top, fz_css_ add_flow_glue(ctx, pool, top, style, "", 0); } +static fz_html_flow *split_flow(fz_context *ctx, fz_pool *pool, fz_html_flow *flow, size_t offset) +{ + fz_html_flow *new_flow; + char *text; + size_t len; + + if (offset == 0) + return flow; + new_flow = fz_pool_alloc(ctx, pool, sizeof *flow); + *new_flow = *flow; + new_flow->next = flow->next; + flow->next = new_flow; + + text = flow->text; + while (*text && offset) + { + int rune; + text += fz_chartorune(&rune, text); + offset--; + } + len = strlen(text); + new_flow->text = fz_pool_alloc(ctx, pool, len+1); + strcpy(new_flow->text, text); + *text = 0; + return new_flow; +} + static int iscjk(int c) { if (c >= 0x3200 && c <= 0x9FFF) return 1; /* CJK Blocks */ @@ -1347,6 +1374,172 @@ fz_layout_html(fz_context *ctx, fz_html *box, float w, float h, float em) layout_block(ctx, box, &page_box, em, h, 0); } +typedef struct +{ + uint16_t *buffer; + size_t max; + size_t len; +} uni_buf; + +typedef struct +{ + fz_context *ctx; + fz_pool *pool; + fz_html_flow *flow; + uni_buf *buffer; +} bidi_data; + +static size_t utf8len(const char *text) +{ + size_t len = 0; + + while (*text) + { + int rune; + text += fz_chartorune(&rune, text); + len++; + } + return len; +} + +static void newFragCb(const uint16_t *fragment, + size_t fragmentLen, + int rightToLeft, + uint16_t mirror, + void *arg) +{ + bidi_data *data = (bidi_data *)arg; + size_t fragmentOffset = fragment - data->buffer->buffer; + int charDirR2L = rightToLeft; + + if((fragmentOffset != 0) && + Bidi_isEuropeanNumber(fragment, fragmentLen)) + { + /* fragment contains digits only */ + charDirR2L = 0; + } + + /* We are guaranteed that fragmentOffset will be at the beginning + * of flow. */ + while (fragmentLen > 0) + { + size_t len; + + if (data->flow->type == FLOW_GLUE) + { + len = 1; + } + else + { + /* Must be text */ + len = utf8len(data->flow->text); + if (len > fragmentLen) + { + /* We need to split this flow box */ + (void)split_flow(data->ctx, data->pool, data->flow, fragmentLen); + len = utf8len(data->flow->text); + } + } + + /* This flow box is entirely contained within this fragment. */ + data->flow->block_r2l = rightToLeft; + data->flow->char_r2l = charDirR2L; + data->flow = data->flow->next; + fragmentOffset += len; + fragmentLen -= len; + } +} + +static void +detect_flow_directionality(fz_context *ctx, fz_pool *pool, uni_buf *buffer, fz_html_flow *flow) +{ + fz_html_flow *end = flow; + const char *text; + bidi_data data; + Bidi_Direction baseDir = -1; + + /* Stage 1: Gather the text from the flow up into a single buffer */ + buffer->len = 0; + while (end) + { + size_t len; + int broken = 0; + + switch (end->type) + { + case FLOW_WORD: + len = utf8len(end->text); + text = end->text; + break; + case FLOW_GLUE: + len = 1; + text = " "; + break; + case FLOW_BREAK: + case FLOW_IMAGE: + broken = 1; + break; + } + + if (broken) + break; + + /* Make sure the buffer is large enough */ + if (buffer->len + len > buffer->max) + { + size_t newmax = buffer->max * 2; + if (newmax == 0) + newmax = 128; /* Sensible small default */ + buffer->buffer = fz_resize_array(ctx, buffer->buffer, newmax, sizeof(uint16_t)); + buffer->max = newmax; + } + + /* Expand the utf8 text into Unicode and store it in the buffer */ + while (*text) + { + int rune; + text += fz_chartorune(&rune, text); + buffer->buffer[buffer->len++] = (uint16_t)rune; + } + + end = end->next; + } + + /* Detect directionality for the buffer */ + data.ctx = ctx; + data.pool = pool; + data.flow = flow; + data.buffer = buffer; + Bidi_fragmentText(ctx, + buffer->buffer, + buffer->len, + &baseDir, + newFragCb, &data, + 0 /* Flags */); +} + +static void +detect_box_directionality(fz_context *ctx, fz_pool *pool, uni_buf *buffer, fz_html *box) +{ + while (box) + { + if (box->flow_head) + { + detect_flow_directionality(ctx, pool, buffer, box->flow_head); + } + detect_box_directionality(ctx, pool, buffer, box->down); + box = box->next; + } +} + +static void +detect_directionality(fz_context *ctx, fz_pool *pool, fz_html *box) +{ + uni_buf buffer = { NULL }; + + detect_box_directionality(ctx, pool, &buffer, box); +} + fz_html * fz_parse_html(fz_context *ctx, fz_html_font_set *set, fz_archive *zip, const char *base_uri, fz_buffer *buf, const char *user_css) { @@ -1380,5 +1573,7 @@ fz_parse_html(fz_context *ctx, fz_html_font_set *set, fz_archive *zip, const cha fz_drop_css(ctx, css); fz_drop_xml(ctx, xml); + detect_directionality(ctx, pool, box); + return box; } |