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And cleaned up the GTK+ code.

This commit is contained in:
Pietro Gagliardi 2017-02-10 15:49:36 -05:00
parent 5823c3a53e
commit 0e5be32299
1 changed files with 22 additions and 104 deletions
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126
unix/drawtext.c
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@ -8,6 +8,7 @@
struct uiDrawTextLayout {
PangoLayout *layout;
uiDrawTextLayoutLineMetrics *lineMetrics;
int nLines;
};
// See https://developer.gnome.org/pango/1.30/pango-Cairo-Rendering.html#pango-Cairo-Rendering.description
@ -48,7 +49,7 @@ static void computeLineMetrics(uiDrawTextLayout *tl)
int i, n;
uiDrawTextLayoutLineMetrics *m;
n = pango_layout_get_line_count(tl->layout);
n = tl->nLines; // TODO remove this variable
tl->lineMetrics = (uiDrawTextLayoutLineMetrics *) uiAlloc(n * sizeof (uiDrawTextLayoutLineMetrics), "uiDrawTextLayoutLineMetrics[] (text layout)");
iter = pango_layout_get_iter(tl->layout);
@ -130,6 +131,7 @@ uiDrawTextLayout *uiDrawNewTextLayout(uiAttributedString *s, uiDrawFontDescripto
// TODO attributes
tl->nLines = pango_layout_get_line_count(tl->layout);
computeLineMetrics(tl);
return tl;
@ -187,93 +189,12 @@ void uiDrawTextLayoutLineGetMetrics(uiDrawTextLayout *tl, int line, uiDrawTextLa
}
#endif
#if 0 /* TODO */
// caret behavior, based on GtkTextView (both 2 and 3) and Qt's text views (both 4 and 5), which are all based on TkTextView:
// - clicking on the right side of a line places the cursor at the beginning of the LAST grapheme on the line
// - pressing Right goes to the first grapheme of the next line, pressing Left goes back to the last grapheme of the original line
// - as such, there is *no* way to get the cursor on the end of the line
// - this includes whitespace, hyphens, and character wraps
// - spaces get special treatment (it seems): you don't see them there and they don't show up if you select one and only one!
// - and the best part is that word processors don't typically do this; they do what other platforms do!
void uiDrawTextLayoutHitTest(uiDrawTextLayout *tl, double x, double y, uiDrawTextLayoutHitTestResult *result)
{
int index;
int trailing;
int line;
int caretX;
double width, height;
// disregard the return value; we do our own bounds checking
// TODO see if there's a way we can use some other function (possibly this one again) to extrapolate more precise bounds information
pango_layout_xy_to_index(tl->layout,
cairoToPango(x), cairoToPango(y),
&index, &trailing);
// figure out what line that was, and also the caret X position since we can get that here too
// TODO should we use the dedicated function instead?
pango_layout_index_to_line_x(tl->layout, index, trailing,
&line, &caretX);
result->Pos = index;
result->Line = line;
uiDrawTextLayoutExtents(tl, &width, &height);
result->XPosition = uiDrawTextLayoutHitTestPositionInside;
if (x < 0)
result->XPosition = uiDrawTextLayoutHitTestPositionBefore;
else if (x >= width)
result->XPosition = uiDrawTextLayoutHitTestPositionAfter;
result->YPosition = uiDrawTextLayoutHitTestPositionInside;
if (y < 0)
result->YPosition = uiDrawTextLayoutHitTestPositionBefore;
else if (y >= height)
result->YPosition = uiDrawTextLayoutHitTestPositionAfter;
result->CaretX = pangoToCairo(caretX);
result->CaretY = tl->lineMetrics[line].Y;
result->CaretHeight = tl->lineMetrics[line].Height;
}
// TODO consider providing a uiDrawTextLayoutByteIndexToCursorPos() function for manual positions by byte index only?
// TODO is this correct for RTL?
void uiDrawTextLayoutByteRangeToRectangle(uiDrawTextLayout *tl, size_t start, size_t end, uiDrawTextLayoutByteRangeRectangle *r)
{
PangoRectangle startRect, endRect;
int line, index;
PangoLayoutLine *pll;
pango_layout_index_to_pos(tl->layout, start, &startRect);
// figure out what line that was
// TODO talk about leading edge here
pango_layout_index_to_line_x(tl->layout, start, 1,
&line, NULL);
pll = pango_layout_get_line_readonly(tl->layout, line);
if (end > (pll->start_index + pll->length))
end = pll->start_index + pll->length;
pango_layout_index_to_pos(tl->layout, end, &endRect);
r->X = pangoToCairo(startRect.x);
r->Y = tl->lineMetrics[line].Y;
r->Width = pangoToCairo(endRect.x) - r->X;
r->Height = tl->lineMetrics[line].Height;
// and figure out the correct start pos
pango_layout_line_x_to_index(pll, startRect.x,
&index, NULL);
r->RealStart = index;
r->RealEnd = end;
// TODO unref pll?
}
#endif
// this algorithm comes from Microsoft's PadWrite sample, following TextEditor::SetSelectionFromPoint()
// TODO this or the next one doesn't work right for the end of a line? it still behaves like TkTextView...
// note: Pango will not let us place the cursor at the end of a line the same way other OSs do; see https://git.gnome.org/browse/pango/tree/pango/pango-layout.c?id=f4cbd27f4e5bf8490ea411190d41813e14f12165#n4204
// ideally there'd be a way to say "I don't need this hack; I'm well behaved" but GTK+ 2 and 3 AND Qt 4 and 5 all behave like this, with the behavior seeming to date back to TkTextView, so...
void uiDrawTextLayoutHitTest(uiDrawTextLayout *tl, double x, double y, size_t *pos, int *line)
{
int p, trailing;
int i;
pango_layout_xy_to_index(tl->layout,
cairoToPango(x), cairoToPango(y),
@ -282,37 +203,34 @@ void uiDrawTextLayoutHitTest(uiDrawTextLayout *tl, double x, double y, size_t *p
// fortunately Pango provides that info directly
if (trailing != 0)
p += trailing;
if (pos != NULL)
*pos = p;
*pos = p;
// TODO do the line detection unconditionally?
// TODO optimize the call to pango_layout_get_line_count()
if (line != NULL) {
int i;
for (i = 0; i < tl->nLines; i++) {
double ltop, lbottom;
for (i = 0; i < pango_layout_get_line_count(tl->layout); i++) {
double ltop, lbottom;
ltop = tl->lineMetrics[i].Y;
lbottom = ltop + tl->lineMetrics[i].Height;
// y will already >= ltop at this point since the past lbottom should == ltop
if (y < lbottom)
break;
}
if (i == pango_layout_get_line_count(tl->layout))
i--;
*line = i;
ltop = tl->lineMetrics[i].Y;
lbottom = ltop + tl->lineMetrics[i].Height;
// y will already >= ltop at this point since the past lbottom should == ltop
if (y < lbottom)
break;
}
if (i == pango_layout_get_line_count(tl->layout))
i--;
*line = i;
}
// TODO find a good API for indicating that this character isn't on the line for when the layout is resized and doing that recalculation...
double uiDrawTextLayoutByteLocationInLine(uiDrawTextLayout *tl, size_t pos, int line)
{
PangoLayoutLine *pll;
gboolean trailing;
int pangox;
if (line < 0 || line >= tl->nLines)
return -1;
pll = pango_layout_get_line_readonly(tl->layout, line);
// note: >, not >=, because the position at end is valid!
if (pos < pll->start_index || pos > (pll->start_index + pll->length))
return -1;
// this behavior seems correct
// there's also PadWrite's TextEditor::GetCaretRect() but that requires state...
// TODO where does this fail?