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-rw-r--r--src/gui/painting/qtextureglyphcache.cpp129
1 files changed, 103 insertions, 26 deletions
diff --git a/src/gui/painting/qtextureglyphcache.cpp b/src/gui/painting/qtextureglyphcache.cpp
index 376219ba8f..92198765f1 100644
--- a/src/gui/painting/qtextureglyphcache.cpp
+++ b/src/gui/painting/qtextureglyphcache.cpp
@@ -47,10 +47,6 @@
#include "private/qnativeimage_p.h"
#include "private/qfontengine_ft_p.h"
-#ifndef QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH
-#define QT_DEFAULT_TEXTURE_GLYPH_CACHE_WIDTH 256
-#endif
-
QT_BEGIN_NAMESPACE
// #define CACHE_DEBUG
@@ -69,8 +65,60 @@ static inline int qt_next_power_of_two(int v)
return v;
}
+int QTextureGlyphCache::calculateSubPixelPositionCount(glyph_t glyph) const
+{
+ // Test 12 different subpixel positions since it factors into 3*4 so it gives
+ // the coverage we need.
+
+ QList<QImage> images;
+ for (int i=0; i<12; ++i) {
+ QImage img = textureMapForGlyph(glyph, QFixed::fromReal(i / 12.0));
+
+ if (images.isEmpty()) {
+ QPainterPath path;
+ QFixedPoint point;
+ m_current_fontengine->addGlyphsToPath(&glyph, &point, 1, &path, QTextItem::RenderFlags());
+
+ // Glyph is space, return 0 to indicate that we need to keep trying
+ if (path.isEmpty())
+ break;
+
+ images.append(img);
+ } else {
+ bool found = false;
+ for (int j=0; j<images.size(); ++j) {
+ if (images.at(j) == img) {
+ found = true;
+ break;
+ }
+ }
+ if (!found)
+ images.append(img);
+ }
+ }
+
+ return images.size();
+}
+
+QFixed QTextureGlyphCache::subPixelPositionForX(QFixed x) const
+{
+ if (m_subPixelPositionCount == 0)
+ return QFixed();
+
+ QFixed subPixelPosition;
+ if (x != 0) {
+ subPixelPosition = x - x.floor();
+ QFixed fraction = (subPixelPosition / QFixed::fromReal(1.0 / m_subPixelPositionCount)).floor();
+
+ // Compensate for precision loss in fixed point to make sure we are always drawing at a subpixel position over
+ // the lower boundary for the selected rasterization by adding 1/64.
+ subPixelPosition = fraction / QFixed(m_subPixelPositionCount) + QFixed::fromReal(0.015625);
+ }
+ return subPixelPosition;
+}
+
void QTextureGlyphCache::populate(QFontEngine *fontEngine, int numGlyphs, const glyph_t *glyphs,
- const QFixedPoint *)
+ const QFixedPoint *positions)
{
#ifdef CACHE_DEBUG
printf("Populating with %d glyphs\n", numGlyphs);
@@ -81,15 +129,33 @@ void QTextureGlyphCache::populate(QFontEngine *fontEngine, int numGlyphs, const
const int margin = glyphMargin();
const int paddingDoubled = glyphPadding() * 2;
- QHash<glyph_t, Coord> listItemCoordinates;
+ bool supportsSubPixelPositions = fontEngine->supportsSubPixelPositions();
+ if (m_subPixelPositionCount == 0) {
+ if (!supportsSubPixelPositions) {
+ m_subPixelPositionCount = 1;
+ } else {
+ int i = 0;
+ while (m_subPixelPositionCount == 0 && i < numGlyphs)
+ m_subPixelPositionCount = calculateSubPixelPositionCount(glyphs[i++]);
+ }
+ }
+
+ QHash<GlyphAndSubPixelPosition, Coord> listItemCoordinates;
int rowHeight = 0;
// check each glyph for its metrics and get the required rowHeight.
for (int i=0; i < numGlyphs; ++i) {
const glyph_t glyph = glyphs[i];
- if (coords.contains(glyph))
+
+ QFixed subPixelPosition;
+ if (supportsSubPixelPositions) {
+ QFixed x = positions != 0 ? positions[i].x : QFixed();
+ subPixelPosition = subPixelPositionForX(x);
+ }
+
+ if (coords.contains(GlyphAndSubPixelPosition(glyph, subPixelPosition)))
continue;
- if (listItemCoordinates.contains(glyph))
+ if (listItemCoordinates.contains(GlyphAndSubPixelPosition(glyph, subPixelPosition)))
continue;
glyph_metrics_t metrics = fontEngine->boundingBox(glyph, m_transform);
@@ -119,7 +185,7 @@ void QTextureGlyphCache::populate(QFontEngine *fontEngine, int numGlyphs, const
metrics.x.round().truncate(),
-metrics.y.truncate() }; // baseline for horizontal scripts
- listItemCoordinates.insert(glyph, c);
+ listItemCoordinates.insert(GlyphAndSubPixelPosition(glyph, subPixelPosition), c);
rowHeight = qMax(rowHeight, glyph_height);
}
if (listItemCoordinates.isEmpty())
@@ -135,17 +201,25 @@ void QTextureGlyphCache::populate(QFontEngine *fontEngine, int numGlyphs, const
}
// now actually use the coords and paint the wanted glyps into cache.
- QHash<glyph_t, Coord>::iterator iter = listItemCoordinates.begin();
+ QHash<GlyphAndSubPixelPosition, Coord>::iterator iter = listItemCoordinates.begin();
+ int requiredWidth = m_w;
while (iter != listItemCoordinates.end()) {
Coord c = iter.value();
m_currentRowHeight = qMax(m_currentRowHeight, c.h + margin * 2);
- if (m_cx + c.w > m_w) {
- // no room on the current line, start new glyph strip
- m_cx = 0;
- m_cy += m_currentRowHeight + paddingDoubled;
- m_currentRowHeight = 0; // New row
+ if (m_cx + c.w > requiredWidth) {
+ int new_width = requiredWidth*2;
+ while (new_width < m_cx + c.w)
+ new_width *= 2;
+ if (new_width <= maxTextureWidth()) {
+ requiredWidth = new_width;
+ } else {
+ // no room on the current line, start new glyph strip
+ m_cx = 0;
+ m_cy += m_currentRowHeight + paddingDoubled;
+ m_currentRowHeight = 0; // New row
+ }
}
c.x = m_cx;
@@ -164,27 +238,30 @@ void QTextureGlyphCache::fillInPendingGlyphs()
if (m_pendingGlyphs.isEmpty())
return;
- int requiredHeight = 0;
+ int requiredHeight = m_h;
+ int requiredWidth = m_w; // Use a minimum size to avoid a lot of initial reallocations
{
- QHash<glyph_t, Coord>::iterator iter = m_pendingGlyphs.begin();
+ QHash<GlyphAndSubPixelPosition, Coord>::iterator iter = m_pendingGlyphs.begin();
while (iter != m_pendingGlyphs.end()) {
Coord c = iter.value();
requiredHeight = qMax(requiredHeight, c.y + c.h);
+ requiredWidth = qMax(requiredWidth, c.x + c.w);
++iter;
}
}
- if (requiredHeight > m_h) {
+ if (isNull() || requiredHeight > m_h || requiredWidth > m_w) {
if (isNull())
- createCache(m_w, qt_next_power_of_two(requiredHeight));
+ createCache(qt_next_power_of_two(requiredWidth), qt_next_power_of_two(requiredHeight));
else
- resizeCache(m_w, qt_next_power_of_two(requiredHeight));
+ resizeCache(qt_next_power_of_two(requiredWidth), qt_next_power_of_two(requiredHeight));
}
{
- QHash<glyph_t, Coord>::iterator iter = m_pendingGlyphs.begin();
+ QHash<GlyphAndSubPixelPosition, Coord>::iterator iter = m_pendingGlyphs.begin();
while (iter != m_pendingGlyphs.end()) {
- fillTexture(iter.value(), iter.key());
+ GlyphAndSubPixelPosition key = iter.key();
+ fillTexture(iter.value(), key.glyph, key.subPixelPosition);
++iter;
}
@@ -193,7 +270,7 @@ void QTextureGlyphCache::fillInPendingGlyphs()
m_pendingGlyphs.clear();
}
-QImage QTextureGlyphCache::textureMapForGlyph(glyph_t g) const
+QImage QTextureGlyphCache::textureMapForGlyph(glyph_t g, QFixed subPixelPosition) const
{
#if defined(Q_WS_X11)
if (m_transform.type() > QTransform::TxTranslate) {
@@ -226,7 +303,7 @@ QImage QTextureGlyphCache::textureMapForGlyph(glyph_t g) const
} else
#endif
if (m_type == QFontEngineGlyphCache::Raster_RGBMask)
- return m_current_fontengine->alphaRGBMapForGlyph(g, glyphMargin(), m_transform);
+ return m_current_fontengine->alphaRGBMapForGlyph(g, subPixelPosition, glyphMargin(), m_transform);
else
return m_current_fontengine->alphaMapForGlyph(g, m_transform);
@@ -272,9 +349,9 @@ int QImageTextureGlyphCache::glyphMargin() const
#endif
}
-void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g)
+void QImageTextureGlyphCache::fillTexture(const Coord &c, glyph_t g, QFixed subPixelPosition)
{
- QImage mask = textureMapForGlyph(g);
+ QImage mask = textureMapForGlyph(g, subPixelPosition);
#ifdef CACHE_DEBUG
printf("fillTexture of %dx%d at %d,%d in the cache of %dx%d\n", c.w, c.h, c.x, c.y, m_image.width(), m_image.height());
generated by cgit v1.2.3 (git 2.25.1) at 2024-05-17 16:05:11 +0000