Ziele Untersuchung
mit Columbo Integrität von
Datenbanken Interaktion und
Portierbarkeit Ergonomie der
Schnittstellen

Angebot Produkte Projekt Beratung

Mittel Analytik Modellierung Sprachen Algebra Logik Hardware Denken Kreativität

Zusammenhänge Gesellschaft Wirtschaft Branche Firma


products/sources/formale Sprachen/C/Firefox/gfx/thebes/ (Browser von der Mozilla Stiftung Version 136.0.1^©) Datei vom 10.2.2025 mit Größe 17 kB

Quelle gfxContext.cpp Sprache: C

/* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
/* vim: set ts=8 sts=2 et sw=2 tw=80: */
/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/. */

#include <math.h>

#include "mozilla/Alignment.h"

#include "cairo.h"

#include "gfxContext.h"

#include "gfxMatrix.h"
#include "gfxUtils.h"
#include "gfxPattern.h"
#include "gfxPlatform.h"

#include "gfx2DGlue.h"
#include "mozilla/gfx/PathHelpers.h"
#include "mozilla/ProfilerLabels.h"
#include <algorithm>
#include "TextDrawTarget.h"

#if XP_WIN
#  include "gfxWindowsPlatform.h"
#  include "mozilla/gfx/DeviceManagerDx.h"
#endif

using namespace mozilla;
using namespace mozilla::gfx;

#ifdef DEBUG
#  define CURRENTSTATE_CHANGED() mAzureState.mContentChanged = true;
#else
#  define CURRENTSTATE_CHANGED()
#endif

PatternFromState::operator Pattern&() {
  const gfxContext::AzureState& state = mContext->mAzureState;

  if (state.pattern) {
    return *state.pattern->GetPattern(
        mContext->mDT,
        state.patternTransformChanged ? &state.patternTransform : nullptr);
  }

  mPattern = new (mColorPattern.addr()) ColorPattern(state.color);
  return *mPattern;
}

/* static */
UniquePtr<gfxContext> gfxContext::CreateOrNull(DrawTarget* aTarget) {
  if (!aTarget || !aTarget->IsValid()) {
    gfxCriticalNote << "Invalid target in gfxContext::CreateOrNull "
                    << hexa(aTarget);
    return nullptr;
  }

  return MakeUnique<gfxContext>(aTarget);
}

gfxContext::~gfxContext() {
  while (!mSavedStates.IsEmpty()) {
    Restore();
  }
  for (unsigned int c = 0; c < mAzureState.pushedClips.Length(); c++) {
    mDT->PopClip();
  }
}

mozilla::layout::TextDrawTarget* gfxContext::GetTextDrawer() const {
  if (mDT->GetBackendType() == BackendType::WEBRENDER_TEXT) {
    return static_cast<mozilla::layout::TextDrawTarget*>(&*mDT);
  }
  return nullptr;
}

void gfxContext::Save() {
  mSavedStates.AppendElement(mAzureState);
  mAzureState.pushedClips.Clear();
#ifdef DEBUG
  mAzureState.mContentChanged = false;
#endif
}

void gfxContext::Restore() {
#ifdef DEBUG
  // gfxContext::Restore is used to restore AzureState. We need to restore it
  // only if it was altered. The following APIs do change the content of
  // AzureState, a user should save the state before using them and restore it
  // after finishing painting:
  // 1. APIs to setup how to paint, such as SetColor()/SetAntialiasMode(). All
  //    gfxContext SetXXXX public functions belong to this category, except
  //    gfxContext::SetPath & gfxContext::SetMatrix.
  // 2. Clip functions, such as Clip() or PopClip(). You may call PopClip()
  //    directly instead of using gfxContext::Save if the clip region is the
  //    only thing that you altered in the target context.
  // 3. Function of setup transform matrix, such as Multiply() and
  //    SetMatrix(). Using gfxContextMatrixAutoSaveRestore is more recommended
  //    if transform data is the only thing that you are going to alter.
  //
  // You will hit the assertion message below if there is no above functions
  // been used between a pair of gfxContext::Save and gfxContext::Restore.
  // Considerate to remove that pair of Save/Restore if hitting that assertion.
  //
  // In the other hand, the following APIs do not alter the content of the
  // current AzureState, therefore, there is no need to save & restore
  // AzureState:
  // 1. constant member functions of gfxContext.
  // 2. Paint calls, such as Line()/Rectangle()/Fill(). Those APIs change the
  //    content of drawing buffer, which is not part of AzureState.
  // 3. Path building APIs, such as SetPath()/MoveTo()/LineTo()/NewPath().
  //    Surprisingly, path information is not stored in AzureState either.
  // Save current AzureState before using these type of APIs does nothing but
  // make performance worse.
  NS_ASSERTION(
      mAzureState.mContentChanged || mAzureState.pushedClips.Length() > 0,
      "The context of the current AzureState is not altered after "
      "Save() been called. you may consider to remove this pair of "
      "gfxContext::Save/Restore.");
#endif

  for (unsigned int c = 0; c < mAzureState.pushedClips.Length(); c++) {
    mDT->PopClip();
  }

  mAzureState = mSavedStates.PopLastElement();

  ChangeTransform(mAzureState.transform, false);
}

// drawing

void gfxContext::Fill(const Pattern& aPattern) {
  AUTO_PROFILER_LABEL("gfxContext::Fill", GRAPHICS);

  CompositionOp op = GetOp();

  if (mPathIsRect) {
    MOZ_ASSERT(!mTransformChanged);

    if (op == CompositionOp::OP_SOURCE) {
      // Emulate cairo operator source which is bound by mask!
      mDT->ClearRect(mRect);
      mDT->FillRect(mRect, aPattern, DrawOptions(1.0f));
    } else {
      mDT->FillRect(mRect, aPattern, DrawOptions(1.0f, op, mAzureState.aaMode));
    }
  } else {
    EnsurePath();
    mDT->Fill(mPath, aPattern, DrawOptions(1.0f, op, mAzureState.aaMode));
  }
}

// XXX snapToPixels is only valid when snapping for filled
// rectangles and for even-width stroked rectangles.
// For odd-width stroked rectangles, we need to offset x/y by
// 0.5...
void gfxContext::Rectangle(const gfxRect& rect, bool snapToPixels) {
  Rect rec = ToRect(rect);

  if (snapToPixels) {
    gfxRect newRect(rect);
    if (UserToDevicePixelSnapped(newRect, SnapOption::IgnoreScale)) {
      gfxMatrix mat = CurrentMatrixDouble();
      if (mat.Invert()) {
        // We need the user space rect.
        rec = ToRect(mat.TransformBounds(newRect));
      } else {
        rec = Rect();
      }
    }
  }

  if (!mPathBuilder && !mPathIsRect) {
    mPathIsRect = true;
    mRect = rec;
    return;
  }

  EnsurePathBuilder();

  mPathBuilder->MoveTo(rec.TopLeft());
  mPathBuilder->LineTo(rec.TopRight());
  mPathBuilder->LineTo(rec.BottomRight());
  mPathBuilder->LineTo(rec.BottomLeft());
  mPathBuilder->Close();
}

void gfxContext::SnappedClip(const gfxRect& rect) {
  Rect rec = ToRect(rect);

  gfxRect newRect(rect);
  if (UserToDevicePixelSnapped(newRect, SnapOption::IgnoreScale)) {
    gfxMatrix mat = CurrentMatrixDouble();
    if (mat.Invert()) {
      // We need the user space rect.
      rec = ToRect(mat.TransformBounds(newRect));
    } else {
      rec = Rect();
    }
  }

  Clip(rec);
}

bool gfxContext::UserToDevicePixelSnapped(gfxRect& rect,
                                          SnapOptions aOptions) const {
  if (mDT->GetUserData(&sDisablePixelSnapping)) {
    return false;
  }

  // if we're not at 1.0 scale, don't snap, unless we're
  // ignoring the scale.  If we're not -just- a scale,
  // never snap.
  const gfxFloat epsilon = 0.0000001;
#define WITHIN_E(a, b) (fabs((a) - (b)) < epsilon)
  Matrix mat = mAzureState.transform;
  if (!aOptions.contains(SnapOption::IgnoreScale) &&
      (!WITHIN_E(mat._11, 1.0) || !WITHIN_E(mat._22, 1.0) ||
       !WITHIN_E(mat._12, 0.0) || !WITHIN_E(mat._21, 0.0))) {
    return false;
  }
#undef WITHIN_E

  gfxPoint p1 = UserToDevice(rect.TopLeft());
  gfxPoint p2 = UserToDevice(rect.TopRight());
  gfxPoint p3 = UserToDevice(rect.BottomRight());

  // Check that the rectangle is axis-aligned. For an axis-aligned rectangle,
  // two opposite corners define the entire rectangle. So check if
  // the axis-aligned rectangle with opposite corners p1 and p3
  // define an axis-aligned rectangle whose other corners are p2 and p4.
  // We actually only need to check one of p2 and p4, since an affine
  // transform maps parallelograms to parallelograms.
  if (!(p2 == gfxPoint(p1.x, p3.y) || p2 == gfxPoint(p3.x, p1.y))) {
    return false;
  }

  if (aOptions.contains(SnapOption::PrioritizeSize)) {
    // Snap the dimensions of the rect, to minimize distortion; only after that
    // will we snap its position. In particular, this guarantees that a square
    // remains square after snapping, which may not be the case if each edge is
    // independently snapped to device pixels.

    // Use the same rounding approach as gfx::BasePoint::Round.
    rect.SizeTo(std::floor(rect.width + 0.5), std::floor(rect.height + 0.5));

    // Find the top-left corner based on the original center and the snapped
    // size, then snap this new corner to the grid.
    gfxPoint center = (p1 + p3) / 2;
    gfxPoint topLeft = center - gfxPoint(rect.width / 2.0, rect.height / 2.0);
    topLeft.Round();
    rect.MoveTo(topLeft);
  } else {
    p1.Round();
    p3.Round();
    rect.MoveTo(gfxPoint(std::min(p1.x, p3.x), std::min(p1.y, p3.y)));
    rect.SizeTo(gfxSize(std::max(p1.x, p3.x) - rect.X(),
                        std::max(p1.y, p3.y) - rect.Y()));
  }

  return true;
}

bool gfxContext::UserToDevicePixelSnapped(gfxPoint& pt,
                                          bool ignoreScale) const {
  if (mDT->GetUserData(&sDisablePixelSnapping)) {
    return false;
  }

  // if we're not at 1.0 scale, don't snap, unless we're
  // ignoring the scale.  If we're not -just- a scale,
  // never snap.
  const gfxFloat epsilon = 0.0000001;
#define WITHIN_E(a, b) (fabs((a) - (b)) < epsilon)
  Matrix mat = mAzureState.transform;
  if (!ignoreScale && (!WITHIN_E(mat._11, 1.0) || !WITHIN_E(mat._22, 1.0) ||
                       !WITHIN_E(mat._12, 0.0) || !WITHIN_E(mat._21, 0.0))) {
    return false;
  }
#undef WITHIN_E

  pt = UserToDevice(pt);
  pt.Round();
  return true;
}

void gfxContext::SetDash(const Float* dashes, int ndash, Float offset,
                         Float devPxScale) {
  CURRENTSTATE_CHANGED()

  mAzureState.dashPattern.SetLength(ndash);
  for (int i = 0; i < ndash; i++) {
    mAzureState.dashPattern[i] = dashes[i] * devPxScale;
  }
  mAzureState.strokeOptions.mDashLength = ndash;
  mAzureState.strokeOptions.mDashOffset = offset * devPxScale;
  mAzureState.strokeOptions.mDashPattern =
      ndash ? mAzureState.dashPattern.Elements() : nullptr;
}

bool gfxContext::CurrentDash(FallibleTArray<Float>& dashes,
                             Float* offset) const {
  if (mAzureState.strokeOptions.mDashLength == 0 ||
      !dashes.Assign(mAzureState.dashPattern, fallible)) {
    return false;
  }

  *offset = mAzureState.strokeOptions.mDashOffset;

  return true;
}

// clipping
void gfxContext::Clip(const Rect& rect) {
  AzureState::PushedClip clip = {nullptr, rect, mAzureState.transform};
  mAzureState.pushedClips.AppendElement(clip);
  mDT->PushClipRect(rect);
  NewPath();
}

void gfxContext::Clip(Path* aPath) {
  mDT->PushClip(aPath);
  AzureState::PushedClip clip = {aPath, Rect(), mAzureState.transform};
  mAzureState.pushedClips.AppendElement(clip);
}

void gfxContext::Clip() {
  if (mPathIsRect) {
    MOZ_ASSERT(!mTransformChanged);

    AzureState::PushedClip clip = {nullptr, mRect, mAzureState.transform};
    mAzureState.pushedClips.AppendElement(clip);
    mDT->PushClipRect(mRect);
  } else {
    EnsurePath();
    mDT->PushClip(mPath);
    AzureState::PushedClip clip = {mPath, Rect(), mAzureState.transform};
    mAzureState.pushedClips.AppendElement(clip);
  }
}

gfxRect gfxContext::GetClipExtents(ClipExtentsSpace aSpace) const {
  Rect rect = GetAzureDeviceSpaceClipBounds();

  if (rect.IsZeroArea()) {
    return gfxRect(0, 0, 0, 0);
  }

  if (aSpace == eUserSpace) {
    Matrix mat = mAzureState.transform;
    mat.Invert();
    rect = mat.TransformBounds(rect);
  }

  return ThebesRect(rect);
}

bool gfxContext::ExportClip(ClipExporter& aExporter) const {
  ForAllClips([&](const AzureState::PushedClip& aClip) -> void {
    gfx::Matrix transform = aClip.transform;
    transform.PostTranslate(-GetDeviceOffset());

    aExporter.BeginClip(transform);
    if (aClip.path) {
      aClip.path->StreamToSink(&aExporter);
    } else {
      aExporter.MoveTo(aClip.rect.TopLeft());
      aExporter.LineTo(aClip.rect.TopRight());
      aExporter.LineTo(aClip.rect.BottomRight());
      aExporter.LineTo(aClip.rect.BottomLeft());
      aExporter.Close();
    }
    aExporter.EndClip();
  });

  return true;
}

// rendering sources

bool gfxContext::GetDeviceColor(DeviceColor& aColorOut) const {
  if (mAzureState.pattern) {
    return mAzureState.pattern->GetSolidColor(aColorOut);
  }

  aColorOut = mAzureState.color;
  return true;
}

already_AddRefed<gfxPattern> gfxContext::GetPattern() const {
  RefPtr<gfxPattern> pat;

  if (mAzureState.pattern) {
    pat = mAzureState.pattern;
  } else {
    pat = new gfxPattern(mAzureState.color);
  }
  return pat.forget();
}

void gfxContext::Paint(Float alpha) const {
  AUTO_PROFILER_LABEL("gfxContext::Paint", GRAPHICS);

  Matrix mat = mDT->GetTransform();
  mat.Invert();
  Rect paintRect = mat.TransformBounds(Rect(Point(0, 0), Size(mDT->GetSize())));

  mDT->FillRect(paintRect, PatternFromState(this), DrawOptions(alpha, GetOp()));
}

#ifdef MOZ_DUMP_PAINTING
void gfxContext::WriteAsPNG(const char* aFile) {
  gfxUtils::WriteAsPNG(mDT, aFile);
}

void gfxContext::DumpAsDataURI() { gfxUtils::DumpAsDataURI(mDT); }

void gfxContext::CopyAsDataURI() { gfxUtils::CopyAsDataURI(mDT); }
#endif

void gfxContext::EnsurePath() {
  if (mPathBuilder) {
    mPath = mPathBuilder->Finish();
    mPathBuilder = nullptr;
  }

  if (mPath) {
    if (mTransformChanged) {
      Matrix mat = mAzureState.transform;
      mat.Invert();
      mat = mPathTransform * mat;
      Path::Transform(mPath, mat);

      mTransformChanged = false;
    }
    return;
  }

  EnsurePathBuilder();
  mPath = mPathBuilder->Finish();
  mPathBuilder = nullptr;
}

void gfxContext::EnsurePathBuilder() {
  if (mPathBuilder && !mTransformChanged) {
    return;
  }

  if (mPath) {
    if (!mTransformChanged) {
      mPathBuilder = Path::ToBuilder(mPath.forget());
    } else {
      Matrix invTransform = mAzureState.transform;
      invTransform.Invert();
      Matrix toNewUS = mPathTransform * invTransform;
      mPathBuilder = Path::ToBuilder(mPath.forget(), toNewUS);
    }
    return;
  }

  DebugOnly<PathBuilder*> oldPath = mPathBuilder.get();

  if (!mPathBuilder) {
    mPathBuilder = mDT->CreatePathBuilder(FillRule::FILL_WINDING);

    if (mPathIsRect) {
      mPathBuilder->MoveTo(mRect.TopLeft());
      mPathBuilder->LineTo(mRect.TopRight());
      mPathBuilder->LineTo(mRect.BottomRight());
      mPathBuilder->LineTo(mRect.BottomLeft());
      mPathBuilder->Close();
    }
  }

  if (mTransformChanged) {
    // This could be an else if since this should never happen when
    // mPathBuilder is nullptr and mPath is nullptr. But this way we can
    // assert if all the state is as expected.
    MOZ_ASSERT(oldPath);
    MOZ_ASSERT(!mPathIsRect);

    Matrix invTransform = mAzureState.transform;
    invTransform.Invert();
    Matrix toNewUS = mPathTransform * invTransform;

    RefPtr<Path> path = mPathBuilder->Finish();
    if (!path) {
      gfxCriticalError()
          << "gfxContext::EnsurePathBuilder failed in PathBuilder::Finish";
    }
    mPathBuilder = Path::ToBuilder(path.forget(), toNewUS);
  }

  mPathIsRect = false;
}

CompositionOp gfxContext::GetOp() const {
  if (mAzureState.op != CompositionOp::OP_SOURCE) {
    return mAzureState.op;
  }

  if (mAzureState.pattern) {
    if (mAzureState.pattern->IsOpaque()) {
      return CompositionOp::OP_OVER;
    } else {
      return CompositionOp::OP_SOURCE;
    }
  } else {
    if (mAzureState.color.a > 0.999) {
      return CompositionOp::OP_OVER;
    } else {
      return CompositionOp::OP_SOURCE;
    }
  }
}

/* SVG font code can change the transform after having set the pattern on the
* context. When the pattern is set it is in user space, if the transform is
* changed after doing so the pattern needs to be converted back into userspace.
* We just store the old pattern transform here so that we only do the work
* needed here if the pattern is actually used.
* We need to avoid doing this when this ChangeTransform comes from a restore,
* since the current pattern and the current transform are both part of the
* state we know the new mAzureState's values are valid. But if we assume
* a change they might become invalid since patternTransformChanged is part of
* the state and might be false for the restored AzureState.
*/
void gfxContext::ChangeTransform(const Matrix& aNewMatrix,
                                 bool aUpdatePatternTransform) {
  if (aUpdatePatternTransform && (mAzureState.pattern) &&
      !mAzureState.patternTransformChanged) {
    mAzureState.patternTransform = GetDTTransform();
    mAzureState.patternTransformChanged = true;
  }

  if (mPathIsRect) {
    Matrix invMatrix = aNewMatrix;

    invMatrix.Invert();

    Matrix toNewUS = mAzureState.transform * invMatrix;

    if (toNewUS.IsRectilinear()) {
      mRect = toNewUS.TransformBounds(mRect);
      mRect.NudgeToIntegers();
    } else {
      mPathBuilder = mDT->CreatePathBuilder(FillRule::FILL_WINDING);

      mPathBuilder->MoveTo(toNewUS.TransformPoint(mRect.TopLeft()));
      mPathBuilder->LineTo(toNewUS.TransformPoint(mRect.TopRight()));
      mPathBuilder->LineTo(toNewUS.TransformPoint(mRect.BottomRight()));
      mPathBuilder->LineTo(toNewUS.TransformPoint(mRect.BottomLeft()));
      mPathBuilder->Close();

      mPathIsRect = false;
    }

    // No need to consider the transform changed now!
    mTransformChanged = false;
  } else if ((mPath || mPathBuilder) && !mTransformChanged) {
    mTransformChanged = true;
    mPathTransform = mAzureState.transform;
  }

  mAzureState.transform = aNewMatrix;

  mDT->SetTransform(GetDTTransform());
}

Rect gfxContext::GetAzureDeviceSpaceClipBounds() const {
  Rect rect(mAzureState.deviceOffset.x + Float(mDT->GetRect().x),
            mAzureState.deviceOffset.y + Float(mDT->GetRect().y),
            Float(mDT->GetSize().width), Float(mDT->GetSize().height));
  ForAllClips([&](const AzureState::PushedClip& aClip) -> void {
    if (aClip.path) {
      rect.IntersectRect(rect, aClip.path->GetBounds(aClip.transform));
    } else {
      rect.IntersectRect(rect, aClip.transform.TransformBounds(aClip.rect));
    }
  });

  return rect;
}

template <typename F>
void gfxContext::ForAllClips(F&& aLambda) const {
  for (const auto& state : mSavedStates) {
    for (const auto& clip : state.pushedClips) {
      aLambda(clip);
    }
  }
  for (const auto& clip : mAzureState.pushedClips) {
    aLambda(clip);
  }
}

quality94%

¤ Dauer der Verarbeitung: 0.18 Sekunden (vorverarbeitet) ¤

Wurzel

Suchen

Beweissystem der NASA

Beweissystem Isabelle

NIST Cobol Testsuite

Cephes Mathematical Library

Wiener Entwicklungsmethode

Haftungshinweis

Die Informationen auf dieser Webseite wurden nach bestem Wissen sorgfältig zusammengestellt. Es wird jedoch weder Vollständigkeit, noch Richtigkeit, noch Qualität der bereit gestellten Informationen zugesichert.