From 5dc68f3285e8659de5c64521bf95a95f7123f849 Mon Sep 17 00:00:00 2001 From: Michael R Sweet Date: Sat, 21 Dec 2024 23:20:36 -0500 Subject: [PATCH] Save work on docos. --- doc/pdfio.md | 241 +++++++++++++++------------------------------------ 1 file changed, 68 insertions(+), 173 deletions(-) diff --git a/doc/pdfio.md b/doc/pdfio.md index 15965f4..dd71910 100644 --- a/doc/pdfio.md +++ b/doc/pdfio.md @@ -1425,9 +1425,8 @@ Four functions handle the formatting of the markdown document: - `format_table`: formats a table. Formatted content is organized into arrays of `linefrag_t` and `tablerow_t` -structures for a line of content or row of table cells, respectively. These -are passed to the `render_line` and `render_row` functions to actually produce -content in the PDF document. +structures for a line of content or row of table cells, respectively. + #### High-Level Formatting @@ -2037,196 +2036,92 @@ format_table(docdata_t *dd, // I - Document data ### Rendering the Markdown Document +The formatted content in arrays of `linefrag_t` and `tablerow_t` structures +are passed to the `render_line` and `render_row` functions respectively to +produce content in the PDF document. + #### Rendering a Line in a Paragraph, Heading, or Table Cell +The `render_line` function adds content from the `linefrag_t` array to a PDF +page. It starts by determining whether a new page is needed: + ```c -static void -render_line(docdata_t *dd, // I - Document data - double margin_left, // I - Left margin - double margin_top, // I - Top margin - double need_bottom, // I - How much space is needed after - double lineheight, // I - Height of line - size_t num_frags, // I - Number of line fragments - linefrag_t *frags) // I - Line fragments +if (!dd->st) { - size_t i; // Looping var - linefrag_t *frag; // Current line fragment - bool in_text = false; // Are we in a text block? + new_page(dd); + margin_top = 0.0; +} +dd->y -= margin_top + lineheight; +if ((dd->y - need_bottom) < dd->art_box.y1) +{ + new_page(dd); - if (!dd->st) - { - new_page(dd); - margin_top = 0.0; - } - - dd->y -= margin_top + lineheight; - if ((dd->y - need_bottom) < dd->art_box.y1) - { - new_page(dd); - - dd->y -= lineheight; - } - - for (i = 0, frag = frags; i < num_frags; i ++, frag ++) - { - if (frag->type == MMD_TYPE_CHECKBOX) - { - // Draw checkbox... - set_color(dd, frag->color); - - if (in_text) - { - pdfioContentTextEnd(dd->st); - in_text = false; - } - - // Add box - pdfioContentPathRect(dd->st, frag->x + 1.0 + margin_left, dd->y, frag->width - 3.0, frag->height - 3.0); - - if (frag->text) - { - // Add check - pdfioContentPathMoveTo(dd->st, frag->x + 3.0 + margin_left, dd->y + 2.0); - pdfioContentPathLineTo(dd->st, frag->x + frag->width - 4.0 + margin_left, dd->y + frag->height - 5.0); - - pdfioContentPathMoveTo(dd->st, frag->x + 3.0 + margin_left, dd->y + frag->height - 5.0); - pdfioContentPathLineTo(dd->st, frag->x + frag->width - 4.0 + margin_left, dd->y + 2.0); - } - - pdfioContentStroke(dd->st); - } - else if (frag->text) - { - // Draw text - if (!in_text) - { - pdfioContentTextBegin(dd->st); - pdfioContentTextMoveTo(dd->st, frag->x + margin_left, dd->y); - - in_text = true; - } - - if (frag->ws && frag->font == DOCFONT_MONOSPACE) - { - set_font(dd, DOCFONT_REGULAR, frag->height); - pdfioContentTextShow(dd->st, UNICODE_VALUE, " "); - } - - set_color(dd, frag->color); - set_font(dd, frag->font, frag->height); - - if (frag->font == DOCFONT_MONOSPACE) - pdfioContentTextShow(dd->st, UNICODE_VALUE, frag->text); - else - pdfioContentTextShowf(dd->st, UNICODE_VALUE, "%s%s", frag->ws ? " " : "", frag->text); - - if (frag->url && dd->num_links < DOCLINK_MAX) - { - doclink_t *l = dd->links + dd->num_links; - // Pointer to this link record - - if (!strcmp(frag->url, "@")) - { - // Use mapped text as link target... - char targetlink[129]; // Targeted link - - targetlink[0] = '#'; - make_target_name(targetlink + 1, frag->text, sizeof(targetlink) - 1); - - l->url = pdfioStringCreate(dd->pdf, targetlink); - } - else if (!strcmp(frag->url, "@@")) - { - // Use literal text as anchor... - l->url = pdfioStringCreatef(dd->pdf, "#%s", frag->text); - } - else - { - // Use URL as-is... - l->url = frag->url; - } - - l->box.x1 = frag->x; - l->box.y1 = dd->y; - l->box.x2 = frag->x + frag->width; - l->box.y2 = dd->y + frag->height; - - dd->num_links ++; - } - } - else - { - // Draw image - char imagename[32]; // Current image name - - if (in_text) - { - pdfioContentTextEnd(dd->st); - in_text = false; - } - - snprintf(imagename, sizeof(imagename), "I%u", (unsigned)frag->imagenum); - pdfioContentDrawImage(dd->st, imagename, frag->x + margin_left, dd->y, frag->width, frag->height); - } - } - - if (in_text) - pdfioContentTextEnd(dd->st); + dd->y -= lineheight; } ``` -#### Rendering a Table Row +We then loops through the fragments for the current line, drawing checkboxes, +images, and text as needed. When a hyperlink is present, we add the link to the +`links` array in the `docdata_t` structure, mapping "@" and "@@" to an internal +link corresponding to the linked text: ```c -static void -render_row(docdata_t *dd, // I - Document data - size_t num_cols, // I - Number of columns - tablecol_t *cols, // I - Column information - tablerow_t *row) // I - Row +if (frag->url && dd->num_links < DOCLINK_MAX) { - size_t col; // Current column - double row_y; // Start of row - docfont_t deffont; // Default font + doclink_t *l = dd->links + dd->num_links; + // Pointer to this link record - - // Start a new page as needed... - if (!dd->st) - new_page(dd); - - if ((dd->y - row->height) < dd->art_box.y1) - new_page(dd); - - if (mmdGetType(row->cells[0]) == MMD_TYPE_TABLE_HEADER_CELL) + if (!strcmp(frag->url, "@")) { - // Header row, no border... - deffont = DOCFONT_BOLD; + // Use mapped text as link target... + char targetlink[129]; // Targeted link + + targetlink[0] = '#'; + make_target_name(targetlink + 1, frag->text, sizeof(targetlink) - 1); + + l->url = pdfioStringCreate(dd->pdf, targetlink); + } + else if (!strcmp(frag->url, "@@")) + { + // Use literal text as anchor... + l->url = pdfioStringCreatef(dd->pdf, "#%s", frag->text); } else { - // Regular body row, add borders... - deffont = DOCFONT_REGULAR; - - set_color(dd, DOCCOLOR_GRAY); - pdfioContentPathRect(dd->st, cols[0].left - TABLE_PADDING, dd->y - row->height, cols[num_cols - 1].right - cols[0].left + 2.0 * TABLE_PADDING, row->height); - for (col = 1; col < num_cols; col ++) - { - pdfioContentPathMoveTo(dd->st, cols[col].left - TABLE_PADDING, dd->y); - pdfioContentPathLineTo(dd->st, cols[col].left - TABLE_PADDING, dd->y - row->height); - } - pdfioContentStroke(dd->st); + // Use URL as-is... + l->url = frag->url; } - row_y = dd->y; + l->box.x1 = frag->x; + l->box.y1 = dd->y; + l->box.x2 = frag->x + frag->width; + l->box.y2 = dd->y + frag->height; - for (col = 0; col < num_cols; col ++) - { - dd->y = row_y; - - format_block(dd, row->cells[col], deffont, SIZE_TABLE, cols[col].left, cols[col].right, /*leader*/NULL); - } - - dd->y = row_y - row->height; + dd->num_links ++; } ``` + +These are later written as annotations in the `add_links` function. + + +#### Rendering a Table Row + +The `render_row` function takes a row of cells and the corresponding column +definitions, draws the border boxes around body cells, and then formats each +cell using the `format_block` function described previously. The key is to +reset the page `y` value before formatting each cell: + +```c +row_y = dd->y; + +for (col = 0; col < num_cols; col ++) +{ + dd->y = row_y; + + format_block(dd, row->cells[col], deffont, SIZE_TABLE, cols[col].left, cols[col].right, /*leader*/NULL); +} + +dd->y = row_y - row->height; +```