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// Copyright (C) 2019 The Qt Company Ltd.
// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR LGPL-3.0-only OR GPL-2.0-only OR GPL-3.0-only
// Qt-Security score:significant reason:default
#include "qsgrhitextureglyphcache_p.h"
#include "qsgdefaultrendercontext_p.h"
#include <qrgb.h>
#include <private/qdrawhelper_p.h>
QT_BEGIN_NAMESPACE
QSGRhiTextureGlyphCache::QSGRhiTextureGlyphCache(QSGDefaultRenderContext *rc,
QFontEngine::GlyphFormat format, const QTransform &matrix,
const QColor &color)
: QImageTextureGlyphCache(format, matrix, color),
m_rc(rc),
m_rhi(rc->rhi())
{
// Some OpenGL implementations, for instance macOS, have issues with
// GL_ALPHA render targets. Similarly, BGRA may be problematic on GLES 2.0.
// So stick with plain image uploads on GL.
m_resizeWithTextureCopy = m_rhi->backend() != QRhi::OpenGLES2;
}
QSGRhiTextureGlyphCache::~QSGRhiTextureGlyphCache()
{
m_rc->deferredReleaseGlyphCacheTexture(m_texture);
}
QRhiTexture *QSGRhiTextureGlyphCache::createEmptyTexture(QRhiTexture::Format format)
{
QRhiTexture *t = m_rhi->newTexture(format, m_size, 1, QRhiTexture::UsedAsTransferSource);
if (!t->create()) {
qWarning("Failed to build new glyph cache texture of size %dx%d", m_size.width(), m_size.height());
return nullptr;
}
QRhiResourceUpdateBatch *resourceUpdates = m_rc->glyphCacheResourceUpdates();
// The new texture must be cleared to 0 always, this cannot be avoided
// otherwise artifacts will occur around the glyphs.
QByteArray data;
if (format == QRhiTexture::RED_OR_ALPHA8)
data.fill(0, m_size.width() * m_size.height());
else
data.fill(0, m_size.width() * m_size.height() * 4);
QRhiTextureSubresourceUploadDescription subresDesc(data.constData(), data.size());
subresDesc.setSourceSize(m_size);
resourceUpdates->uploadTexture(t, QRhiTextureUploadEntry(0, 0, subresDesc));
return t;
}
void QSGRhiTextureGlyphCache::createTextureData(int width, int height)
{
width = qMax(128, width);
height = qMax(32, height);
if (!m_resizeWithTextureCopy)
QImageTextureGlyphCache::createTextureData(width, height);
m_size = QSize(width, height);
}
void QSGRhiTextureGlyphCache::resizeTextureData(int width, int height)
{
width = qMax(128, width);
height = qMax(32, height);
if (m_size.width() >= width && m_size.height() >= height)
return;
m_size = QSize(width, height);
if (m_texture) {
QRhiTexture *t = createEmptyTexture(m_texture->format());
if (!t)
return;
QRhiResourceUpdateBatch *resourceUpdates = m_rc->glyphCacheResourceUpdates();
if (m_resizeWithTextureCopy) {
resourceUpdates->copyTexture(t, m_texture);
} else {
QImageTextureGlyphCache::resizeTextureData(width, height);
QImage img = image();
prepareGlyphImage(&img);
QRhiTextureSubresourceUploadDescription subresDesc(img);
const QSize oldSize = m_texture->pixelSize();
subresDesc.setSourceSize(QSize(qMin(oldSize.width(), width), qMin(oldSize.height(), height)));
resourceUpdates->uploadTexture(t, QRhiTextureUploadEntry(0, 0, subresDesc));
}
m_rc->deferredReleaseGlyphCacheTexture(m_texture);
m_texture = t;
}
}
void QSGRhiTextureGlyphCache::beginFillTexture()
{
Q_ASSERT(m_uploads.isEmpty());
}
void QSGRhiTextureGlyphCache::prepareGlyphImage(QImage *img)
{
const int maskWidth = img->width();
const int maskHeight = img->height();
#if Q_BYTE_ORDER != Q_BIG_ENDIAN
const bool supportsBgra = m_rhi->isTextureFormatSupported(QRhiTexture::BGRA8);
#endif
m_bgra = false;
if (img->format() == QImage::Format_Mono) {
*img = std::move(*img).convertToFormat(QImage::Format_Grayscale8);
} else if (img->format() == QImage::Format_RGB32 || img->format() == QImage::Format_ARGB32_Premultiplied) {
// We need to make the alpha component equal to the average of the RGB values.
// This is needed when drawing sub-pixel antialiased text on translucent targets.
if (img->format() == QImage::Format_RGB32
#if Q_BYTE_ORDER != Q_BIG_ENDIAN
|| !supportsBgra
#endif
) {
for (int y = 0; y < maskHeight; ++y) {
QRgb *src = reinterpret_cast<QRgb *>(img->scanLine(y));
for (int x = 0; x < maskWidth; ++x) {
QRgb &rgb = src[x];
if (img->format() == QImage::Format_RGB32) {
int r = qRed(rgb);
int g = qGreen(rgb);
int b = qBlue(rgb);
int avg = (r + g + b + 1) / 3; // "+1" for rounding.
rgb = qRgba(r, g, b, avg);
}
#if Q_BYTE_ORDER != Q_BIG_ENDIAN
if (!supportsBgra) {
// swizzle the bits to accommodate for the RGBA upload.
rgb = ARGB2RGBA(rgb);
m_bgra = false;
}
#endif
}
}
}
#if Q_BYTE_ORDER != Q_BIG_ENDIAN
if (supportsBgra)
m_bgra = true;
#endif
}
}
void QSGRhiTextureGlyphCache::fillTexture(const Coord &c, glyph_t glyph, const QFixedPoint &subPixelPosition)
{
QRhiTextureSubresourceUploadDescription subresDesc;
QImage mask;
if (!m_resizeWithTextureCopy) {
QImageTextureGlyphCache::fillTexture(c, glyph, subPixelPosition);
// Explicitly copy() here to avoid fillTexture detaching the *entire* image() when
// it is still referenced by QRhiTextureSubresourceUploadDescription.
mask = image().copy(QRect(c.x, c.y, c.w, c.h));
} else {
mask = textureMapForGlyph(glyph, subPixelPosition);
}
prepareGlyphImage(&mask);
subresDesc.setImage(mask);
subresDesc.setDestinationTopLeft(QPoint(c.x, c.y));
m_uploads.append(QRhiTextureUploadEntry(0, 0, subresDesc));
}
void QSGRhiTextureGlyphCache::endFillTexture()
{
if (m_uploads.isEmpty())
return;
if (!m_texture) {
QRhiTexture::Format texFormat;
if (m_format == QFontEngine::Format_A32 || m_format == QFontEngine::Format_ARGB)
texFormat = m_bgra ? QRhiTexture::BGRA8 : QRhiTexture::RGBA8;
else // should be R8, but there is the OpenGL ES 2.0 nonsense
texFormat = QRhiTexture::RED_OR_ALPHA8;
m_texture = createEmptyTexture(texFormat);
if (!m_texture)
return;
}
QRhiResourceUpdateBatch *resourceUpdates = m_rc->glyphCacheResourceUpdates();
QRhiTextureUploadDescription desc;
desc.setEntries(m_uploads.cbegin(), m_uploads.cend());
resourceUpdates->uploadTexture(m_texture, desc);
m_uploads.clear();
}
int QSGRhiTextureGlyphCache::glyphPadding() const
{
if (m_format == QFontEngine::Format_Mono)
return 8;
else
return 1;
}
int QSGRhiTextureGlyphCache::maxTextureWidth() const
{
return m_rhi->resourceLimit(QRhi::TextureSizeMax);
}
int QSGRhiTextureGlyphCache::maxTextureHeight() const
{
if (!m_resizeWithTextureCopy)
return qMin(1024, m_rhi->resourceLimit(QRhi::TextureSizeMax));
return m_rhi->resourceLimit(QRhi::TextureSizeMax);
}
void QSGRhiTextureGlyphCache::commitResourceUpdates(QRhiResourceUpdateBatch *mergeInto)
{
if (QRhiResourceUpdateBatch *resourceUpdates = m_rc->maybeGlyphCacheResourceUpdates()) {
mergeInto->merge(resourceUpdates);
m_rc->resetGlyphCacheResources();
}
}
bool QSGRhiTextureGlyphCache::eightBitFormatIsAlphaSwizzled() const
{
// return true when the shaders for 8-bit formats need .a instead of .r
// when sampling the texture
return !m_rhi->isFeatureSupported(QRhi::RedOrAlpha8IsRed);
}
QT_END_NAMESPACE