From 5d57261b9c5085e060a29dfc6f54c70ac92ae559 Mon Sep 17 00:00:00 2001 From: nulano Date: Tue, 21 Apr 2020 22:44:28 +0200 Subject: [PATCH] fix text clipping due to rounding (cherry picked from commit 35500aad08fb18a904f326df2ce8c59ae6413801) --- src/_imagingft.c | 199 +++++++++++++++++++---------------------------- 1 file changed, 80 insertions(+), 119 deletions(-) diff --git a/src/_imagingft.c b/src/_imagingft.c index 3baf0a939..27af44454 100644 --- a/src/_imagingft.c +++ b/src/_imagingft.c @@ -612,7 +612,7 @@ font_getsize(FontObject* self, PyObject* args) int position, advanced; int x_max, x_min, y_max, y_min; FT_Face face; - int xoffset, yoffset; + int x_anchor, y_anchor; int horizontal_dir; int mask = 0; int load_flags; @@ -621,6 +621,7 @@ font_getsize(FontObject* self, PyObject* args) size_t i, count; GlyphInfo *glyph_info = NULL; PyObject *features = Py_None; + FT_Vector pen; /* calculate size and bearing for a given string */ @@ -643,6 +644,29 @@ font_getsize(FontObject* self, PyObject* args) FT_Glyph glyph; face = self->face; index = glyph_info[i].index; + + if (horizontal_dir) { + pen.x = position + glyph_info[i].x_offset; + pen.y = glyph_info[i].y_offset; + + position += glyph_info[i].x_advance; + advanced = PIXEL(position); + if (advanced > x_max) { + x_max = advanced; + } + } else { + pen.x = glyph_info[i].x_offset; + pen.y = position + glyph_info[i].y_offset; + + position += glyph_info[i].y_advance; + advanced = PIXEL(position); + if (advanced < y_min) { + y_min = advanced; + } + } + + FT_Set_Transform(face, NULL, &pen); + /* Note: bitmap fonts within ttf fonts do not work, see #891/pr#960 * Yifu Yu, 2014-10-15 */ @@ -655,74 +679,24 @@ font_getsize(FontObject* self, PyObject* args) return geterror(error); } - FT_Get_Glyph(face->glyph, &glyph); - FT_Glyph_Get_CBox(glyph, FT_GLYPH_BBOX_SUBPIXELS, &bbox); - if (horizontal_dir) { - // adjust start position if glyph bearing extends before origin - offset = position + face->glyph->metrics.horiBearingX + glyph_info[i].x_offset; - if (offset < x_min) { - x_min = offset; - } - - position += glyph_info[i].x_advance; - advanced = position; + error = FT_Get_Glyph(face->glyph, &glyph); + if (error) { + return geterror(error); + } - // adjust glyph end position if bearing extends past advanced point - offset = glyph_info[i].x_advance - - glyph_info[i].x_offset - - face->glyph->metrics.horiBearingX - - face->glyph->metrics.width; - if (offset < 0) { - advanced -= offset; - } - if (advanced > x_max) { - x_max = advanced; - } + FT_Glyph_Get_CBox(glyph, FT_GLYPH_BBOX_PIXELS, &bbox); - bbox.yMax += glyph_info[i].y_offset; - bbox.yMin += glyph_info[i].y_offset; - if (bbox.yMax > y_max) { - y_max = bbox.yMax; - } - if (bbox.yMin < y_min) { - y_min = bbox.yMin; - } - } else { - // NOTE: harfbuzz (called from raqm) assumes that we are using horizontal - // bearings even for vertical text and adjusts offsets to compensate as follows: - // hb-ft.cc: hb_ft_get_glyph_v_origin(): - // x_offset += horiBearingX - vertBearingX; - // y_offset += horiBearingY - (-vertBearingY); - - // adjust start position if glyph bearing extends before origin - offset = position + face->glyph->metrics.horiBearingY + glyph_info[i].y_offset; - if (offset > y_max) { - y_max = offset; - } - - position += glyph_info[i].y_advance; - advanced = position; - - // adjust glyph end position if bearing extends past advanced point - offset = glyph_info[i].y_advance - - glyph_info[i].y_offset - - face->glyph->metrics.horiBearingY + - face->glyph->metrics.height; - if (offset > 0) { - advanced -= offset; - } - if (advanced < y_min) { - y_min = advanced; - } - - bbox.xMax += glyph_info[i].x_offset; - bbox.xMin += glyph_info[i].x_offset; - if (bbox.xMax > x_max) { - x_max = bbox.xMax; - } - if (bbox.xMin < x_min) { - x_min = bbox.xMin; - } + if (bbox.xMax > x_max) { + x_max = bbox.xMax; + } + if (bbox.xMin < x_min) { + x_min = bbox.xMin; + } + if (bbox.yMax > y_max) { + y_max = bbox.yMax; + } + if (bbox.yMin < y_min) { + y_min = bbox.yMin; } FT_Done_Glyph(glyph); @@ -733,21 +707,23 @@ font_getsize(FontObject* self, PyObject* args) glyph_info = NULL; } + x_anchor = y_anchor = 0; if (face) { + FT_Set_Transform(face, NULL, NULL); if (horizontal_dir) { - xoffset = 0; - yoffset = self->face->size->metrics.ascender - y_max; + x_anchor = 0; + y_anchor = PIXEL(self->face->size->metrics.ascender); } else { - xoffset = 0; - yoffset = -y_max; + x_anchor = x_min; + y_anchor = 0; } } return Py_BuildValue( "(ii)(ii)", - PIXEL(x_max - x_min), PIXEL(y_max - y_min), - PIXEL(xoffset), PIXEL(yoffset) - ); + (x_max - x_min), (y_max - y_min), + (-x_anchor + x_min), -(-y_anchor + y_max) + ); } static PyObject* @@ -777,6 +753,7 @@ font_render(FontObject* self, PyObject* args) size_t i, count; GlyphInfo *glyph_info; PyObject *features = NULL; + FT_Vector pen; if (!PyArg_ParseTuple(args, "On|izOzi:render", &string, &id, &mask, &dir, &features, &lang, &stroke_width)) { @@ -808,10 +785,15 @@ font_render(FontObject* self, PyObject* args) load_flags |= FT_LOAD_TARGET_MONO; } - x = y = baseline = offset = 0; + pen.x = pen.y = x = y = baseline = offset = 0; horizontal_dir = (dir && strcmp(dir, "ttb") == 0) ? 0 : 1; for (i = 0; i < count; i++) { index = glyph_info[i].index; + + pen.x = x + glyph_info[i].x_offset; + pen.y = y + glyph_info[i].y_offset; + FT_Set_Transform(self->face, NULL, &pen); + error = FT_Load_Glyph(self->face, index, load_flags | FT_LOAD_RENDER); if (error) { return geterror(error); @@ -822,40 +804,30 @@ font_render(FontObject* self, PyObject* args) // compute baseline and adjust start position if glyph bearing extends before origin if (horizontal_dir) { - temp = glyph_slot->metrics.horiBearingY + glyph_info[i].y_offset; - if (temp > baseline) { - baseline = temp; + if (glyph_slot->bitmap_top > baseline) { + baseline = glyph_slot->bitmap_top; } - - temp = x + glyph_slot->metrics.horiBearingX + glyph_info[i].x_offset; - if (temp < offset) { - offset = temp; + if (glyph_slot->bitmap_left < offset) { + offset = glyph_slot->bitmap_left; } x += glyph_info[i].x_advance; } else { - // NOTE: harfbuzz (called from raqm) assumes that we are using horizontal - // bearings even for vertical text and adjusts offsets to compensate as follows: - // hb-ft.cc: hb_ft_get_glyph_v_origin(): - // x_offset += horiBearingX - vertBearingX; - // y_offset += horiBearingY - (-vertBearingY); - - temp = -(glyph_slot->metrics.horiBearingX + glyph_info[i].x_offset); - if (temp > baseline) { - baseline = temp; + if (glyph_slot->bitmap_top > offset) { + offset = glyph_slot->bitmap_top; } - - temp = y + glyph_slot->metrics.horiBearingY + glyph_info[i].y_offset; - if (temp > offset) { - offset = temp; + if (glyph_slot->bitmap_left < baseline) { + baseline = glyph_slot->bitmap_left; } y += glyph_info[i].y_advance; } } if (horizontal_dir) { - x = -offset; + x = (-offset + stroke_width) * 64; + y = (-baseline + (-stroke_width)) * 64; } else { - y = -offset; + x = (-baseline + stroke_width) * 64; + y = (-offset + (-stroke_width)) * 64; } if (stroker == NULL) { @@ -864,6 +836,11 @@ font_render(FontObject* self, PyObject* args) for (i = 0; i < count; i++) { index = glyph_info[i].index; + + pen.x = x + glyph_info[i].x_offset; + pen.y = y + glyph_info[i].y_offset; + FT_Set_Transform(self->face, NULL, &pen); + error = FT_Load_Glyph(self->face, index, load_flags); if (error) { return geterror(error); @@ -886,19 +863,12 @@ font_render(FontObject* self, PyObject* args) bitmap_glyph = (FT_BitmapGlyph)glyph; bitmap = bitmap_glyph->bitmap; + xx = bitmap_glyph->left; + yy = -bitmap_glyph->top; } else { bitmap = glyph_slot->bitmap; - } - - // NOTE: harfbuzz (called from raqm) assumes that we are using horizontal - // bearings even for vertical text and adjusts offsets to compensate as follows: - // hb-ft.cc: hb_ft_get_glyph_v_origin(): - // x_offset += horiBearingX - vertBearingX; - // y_offset += horiBearingY - (-vertBearingY); - if (horizontal_dir) { - xx = PIXEL(x + glyph_slot->metrics.horiBearingX + glyph_info[i].x_offset); - } else { - xx = PIXEL(baseline + glyph_slot->metrics.horiBearingX + glyph_info[i].x_offset); + xx = glyph_slot->bitmap_left; + yy = -glyph_slot->bitmap_top; } x0 = 0; @@ -911,17 +881,7 @@ font_render(FontObject* self, PyObject* args) } source = (unsigned char*) bitmap.buffer; - for (bitmap_y = 0; bitmap_y < bitmap.rows; bitmap_y++) { - // NOTE: harfbuzz (called from raqm) assumes that we are using horizontal - // bearings even for vertical text and adjusts offsets to compensate as follows: - // hb-ft.cc: hb_ft_get_glyph_v_origin(): - // x_offset += horiBearingX - vertBearingX; - // y_offset += horiBearingY - (-vertBearingY); - if (horizontal_dir) { - yy = PIXEL(baseline - glyph_slot->metrics.horiBearingY - glyph_info[i].y_offset) + bitmap_y; - } else { - yy = PIXEL(-(y + glyph_slot->metrics.horiBearingY + glyph_info[i].y_offset)) + bitmap_y; - } + for (bitmap_y = 0; bitmap_y < bitmap.rows; bitmap_y++, yy++) { if (yy >= 0 && yy < im->ysize) { // blend this glyph into the buffer unsigned char *target = im->image8[yy] + xx; @@ -956,6 +916,7 @@ font_render(FontObject* self, PyObject* args) } } + FT_Set_Transform(self->face, NULL, NULL); FT_Stroker_Done(stroker); PyMem_Del(glyph_info); Py_RETURN_NONE;