DEV/flutter_flutter
1
0
Fork 0
mirror of https://github.com/flutter/flutter.git synced 2026-02-20 02:29:02 +08:00
Code Issues Packages Projects Releases Wiki Activity

Account for glyph extents in the atlas. (flutter/engine#42)

Browse Source
This commit is contained in:
Chinmay Garde 2022-02-28 12:55:43 -08:00 committed by Dan Field
parent b279ee5d8e
commit 8eec77df35
5 changed files with 70 additions and 41 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
engine/src/flutter/impeller/entity/contents.cc
View File

@ -635,11 +635,7 @@ bool TextContents::Render(const ContentContext& renderer,
// Iterate through all the runs in the blob.
for (const auto& run : frame_.GetRuns()) {
auto font = run.GetFont();
auto glyph_size = font.GetGlyphSize();
if (!glyph_size.has_value()) {
VALIDATION_LOG << "Glyph has no size.";
return false;
}
auto glyph_size = ISize::Ceil(font.GetMetrics().GetBoundingBox().size);
// Draw each glyph individually. This should probably be batched.
for (const auto& glyph_position : run.GetGlyphPositions()) {
FontGlyphPair font_glyph_pair{font, glyph_position.glyph};
@ -651,9 +647,9 @@ bool TextContents::Render(const ContentContext& renderer,
VS::GlyphInfo glyph_info;
glyph_info.position = glyph_position.position.Translate(
{0.0, font.GetMetrics().ascent, 0.0});
glyph_info.glyph_size = {static_cast<Scalar>(glyph_size->width),
static_cast<Scalar>(glyph_size->height)};
{font.GetMetrics().min_extent.x, font.GetMetrics().ascent, 0.0});
glyph_info.glyph_size = {static_cast<Scalar>(glyph_size.width),
static_cast<Scalar>(glyph_size.height)};
glyph_info.atlas_position = atlas_glyph_pos->origin;
glyph_info.atlas_glyph_size = {atlas_glyph_pos->size.width,
atlas_glyph_pos->size.height};

2
engine/src/flutter/impeller/typographer/backends/skia/text_frame_skia.cc
View File

@ -22,6 +22,8 @@ static Font ToFont(const SkFont& font) {
metrics.point_size = font.getSize();
metrics.ascent = sk_metrics.fAscent;
metrics.descent = sk_metrics.fDescent;
metrics.min_extent = {sk_metrics.fXMin, sk_metrics.fTop};
metrics.max_extent = {sk_metrics.fXMax, sk_metrics.fBottom};
return Font{std::move(typeface), std::move(metrics)};
}

56
engine/src/flutter/impeller/typographer/backends/skia/text_render_context_skia.cc
View File

@ -62,21 +62,19 @@ static bool PairsFitInAtlasOfSize(const FontGlyphPair::Vector& pairs,
glyph_positions.reserve(pairs.size());
for (const auto& pair : pairs) {
auto glyph_size = pair.font.GetGlyphSize();
if (!glyph_size.has_value()) {
continue;
}
const auto glyph_size =
ISize::Ceil(pair.font.GetMetrics().GetBoundingBox().size);
SkIPoint16 location_in_atlas;
if (!rect_packer->addRect(glyph_size->width, //
glyph_size->height, //
&location_in_atlas //
if (!rect_packer->addRect(glyph_size.width, //
glyph_size.height, //
&location_in_atlas //
)) {
return false;
}
glyph_positions.emplace_back(Rect::MakeXYWH(location_in_atlas.x(), //
location_in_atlas.y(), //
glyph_size->width, //
glyph_size->height //
glyph_size.width, //
glyph_size.height //
));
}
@ -122,22 +120,46 @@ static std::optional<SkBitmap> CreateAtlasBitmap(const GlyphAtlas& atlas,
const Rect& location) -> bool {
const auto position = SkPoint::Make(location.origin.x, location.origin.y);
SkGlyphID glyph_id = font_glyph.glyph.index;
SkFont font(
SkFont sk_font(
TypefaceSkia::Cast(*font_glyph.font.GetTypeface()).GetSkiaTypeface(),
font_glyph.font.GetMetrics().point_size);
SkFontMetrics metrics;
font.getMetrics(&metrics);
const auto& metrics = font_glyph.font.GetMetrics();
auto glyph_color = SK_ColorWHITE;
#if 0
{
glyph_color = SkColorSetARGB(255, //
std::rand() % 255, //
std::rand() % 255, //
std::rand() % 255 //
);
SkPaint debug_paint;
debug_paint.setARGB(255 / 4, //
std::rand() % 255, //
std::rand() % 255, //
std::rand() % 255 //
);
canvas->drawRect(SkRect::MakeXYWH(location.origin.x, //
location.origin.y, //
location.size.width, //
location.size.height //
),
debug_paint);
}
#endif
SkPaint glyph_paint;
glyph_paint.setColor(SK_ColorWHITE);
glyph_paint.setColor(glyph_color);
canvas->drawGlyphs(1u, // count
&glyph_id, // glyphs
&position, // positions
SkPoint::Make(0.0,
-metrics.fAscent), // origin
font, // font
glyph_paint // paint
SkPoint::Make(-metrics.min_extent.x,
-metrics.ascent), // origin
sk_font, // font
glyph_paint // paint
);
return true;
});

7
engine/src/flutter/impeller/typographer/font.cc
View File

@ -34,13 +34,6 @@ bool Font::IsEqual(const Font& other) const {
is_valid_ == other.is_valid_ && metrics_ == other.metrics_;
}
std::optional<ISize> Font::GetGlyphSize() const {
if (!IsValid()) {
return std::nullopt;
}
return ISize::Ceil(typeface_->GetBoundingBox().size * metrics_.point_size);
}
const Font::Metrics& Font::GetMetrics() const {
return metrics_;
}

34
engine/src/flutter/impeller/typographer/font.h
View File

@ -44,10 +44,34 @@ class Font : public Comparable<Font> {
/// yields larger numbers.
///
Scalar descent = 0.0f;
//--------------------------------------------------------------------------
/// The minimum glyph extents relative to the origin. Typically negative in
/// an upper-left-origin coordinate system.
///
Point min_extent;
//--------------------------------------------------------------------------
/// The maximum glyph extents relative to the origin. Typically positive in
/// an upper-left-origin coordinate system.
///
Point max_extent;
//--------------------------------------------------------------------------
/// @brief The union of the bounding boxes of all the glyphs.
///
/// @return The bounding box.
///
constexpr Rect GetBoundingBox() const {
return Rect::MakeLTRB(min_extent.x, //
min_extent.y, //
max_extent.x, //
max_extent.y //
);
}
constexpr bool operator==(const Metrics& o) const {
return point_size == o.point_size && ascent == o.ascent &&
descent == o.descent;
descent == o.descent && min_extent == o.min_extent &&
max_extent == o.max_extent;
}
};
@ -64,14 +88,6 @@ class Font : public Comparable<Font> {
///
const std::shared_ptr<Typeface>& GetTypeface() const;
//----------------------------------------------------------------------------
/// @brief A conservatively large scaled bounding box of all glyphs in
/// this font.
///
/// @return The scaled glyph size.
///
std::optional<ISize> GetGlyphSize() const;
const Metrics& GetMetrics() const;
// |Comparable<Font>|