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gfxWindowsNativeDrawing.cpp (10661B)


      1 /* -*- Mode: C++; tab-width: 20; indent-tabs-mode: nil; c-basic-offset: 2 -*-
      2 * This Source Code Form is subject to the terms of the Mozilla Public
      3 * License, v. 2.0. If a copy of the MPL was not distributed with this
      4 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
      5 
      6 #include <windows.h>
      7 
      8 #include "nsMathUtils.h"
      9 
     10 #include "gfxWindowsNativeDrawing.h"
     11 #include "gfxWindowsSurface.h"
     12 #include "gfxAlphaRecovery.h"
     13 #include "gfxPattern.h"
     14 #include "mozilla/gfx/2D.h"
     15 #include "mozilla/gfx/Helpers.h"
     16 #include "gfx2DGlue.h"
     17 
     18 #include "cairo.h"
     19 #include "cairo-win32.h"
     20 
     21 using namespace mozilla;
     22 using namespace mozilla::gfx;
     23 
     24 enum {
     25  RENDER_STATE_INIT,
     26 
     27  RENDER_STATE_NATIVE_DRAWING,
     28  RENDER_STATE_NATIVE_DRAWING_DONE,
     29 
     30  RENDER_STATE_ALPHA_RECOVERY_BLACK,
     31  RENDER_STATE_ALPHA_RECOVERY_BLACK_DONE,
     32  RENDER_STATE_ALPHA_RECOVERY_WHITE,
     33  RENDER_STATE_ALPHA_RECOVERY_WHITE_DONE,
     34 
     35  RENDER_STATE_DONE
     36 };
     37 
     38 gfxWindowsNativeDrawing::gfxWindowsNativeDrawing(gfxContext* ctx,
     39                                                 const gfxRect& nativeRect,
     40                                                 uint32_t nativeDrawFlags)
     41    : mContext(ctx),
     42      mNativeRect(nativeRect),
     43      mNativeDrawFlags(nativeDrawFlags),
     44      mRenderState(RENDER_STATE_INIT) {}
     45 
     46 HDC gfxWindowsNativeDrawing::BeginNativeDrawing() {
     47  if (mRenderState == RENDER_STATE_INIT) {
     48    RefPtr<gfxASurface> surf;
     49    DrawTarget* drawTarget = mContext->GetDrawTarget();
     50    cairo_t* cairo = nullptr;
     51    if (drawTarget->GetBackendType() == BackendType::CAIRO) {
     52      cairo = static_cast<cairo_t*>(
     53          drawTarget->GetNativeSurface(NativeSurfaceType::CAIRO_CONTEXT));
     54      if (cairo) {
     55        cairo_surface_t* s = cairo_get_group_target(cairo);
     56        if (s) {
     57          mDeviceOffset = mContext->GetDeviceOffset();
     58          double sdx, sdy;
     59          cairo_surface_get_device_offset(s, &sdx, &sdy);
     60          mDeviceOffset.x -= sdx;
     61          mDeviceOffset.y -= sdy;
     62          surf = gfxASurface::Wrap(s);
     63        }
     64      }
     65    }
     66 
     67    if (surf && surf->CairoStatus() != 0) return nullptr;
     68 
     69    gfxMatrix m = mContext->CurrentMatrixDouble();
     70    if (!m.HasNonTranslation())
     71      mTransformType = TRANSLATION_ONLY;
     72    else if (m.HasNonAxisAlignedTransform())
     73      mTransformType = COMPLEX;
     74    else
     75      mTransformType = AXIS_ALIGNED_SCALE;
     76 
     77    // if this is a native win32 surface, we don't have to
     78    // redirect rendering to our own HDC; in some cases,
     79    // we may be able to use the HDC from the surface directly.
     80    if (surf && ((surf->GetType() == gfxSurfaceType::Win32 ||
     81                  surf->GetType() == gfxSurfaceType::Win32Printing) &&
     82                 (surf->GetContentType() == gfxContentType::COLOR ||
     83                  (surf->GetContentType() == gfxContentType::COLOR_ALPHA &&
     84                   (mNativeDrawFlags & CAN_DRAW_TO_COLOR_ALPHA))))) {
     85      // grab the DC. This can fail if there is a complex clipping path,
     86      // in which case we'll have to fall back.
     87      mWinSurface = static_cast<gfxWindowsSurface*>(
     88          static_cast<gfxASurface*>(surf.get()));
     89      mDC = cairo_win32_get_dc_with_clip(cairo);
     90 
     91      if (mDC) {
     92        if (mTransformType == TRANSLATION_ONLY) {
     93          mRenderState = RENDER_STATE_NATIVE_DRAWING;
     94 
     95          mTranslation = m.GetTranslation();
     96        } else if (((mTransformType == AXIS_ALIGNED_SCALE) &&
     97                    (mNativeDrawFlags & CAN_AXIS_ALIGNED_SCALE)) ||
     98                   (mNativeDrawFlags & CAN_COMPLEX_TRANSFORM)) {
     99          mWorldTransform.eM11 = (FLOAT)m._11;
    100          mWorldTransform.eM12 = (FLOAT)m._12;
    101          mWorldTransform.eM21 = (FLOAT)m._21;
    102          mWorldTransform.eM22 = (FLOAT)m._22;
    103          mWorldTransform.eDx = (FLOAT)m._31;
    104          mWorldTransform.eDy = (FLOAT)m._32;
    105 
    106          mRenderState = RENDER_STATE_NATIVE_DRAWING;
    107        }
    108      }
    109    }
    110 
    111    // If we couldn't do native drawing, then we have to do two-buffer drawing
    112    // and do alpha recovery
    113    if (mRenderState == RENDER_STATE_INIT) {
    114      mRenderState = RENDER_STATE_ALPHA_RECOVERY_BLACK;
    115 
    116      // We round out our native rect here, that way the snapping will
    117      // happen correctly.
    118      mNativeRect.RoundOut();
    119 
    120      // we only do the scale bit if we can do an axis aligned
    121      // scale; otherwise we scale (if necessary) after
    122      // rendering with cairo.  Note that if we're doing alpha recovery,
    123      // we cannot do a full complex transform with win32 (I mean, we could, but
    124      // it would require more code that's not here.)
    125      if (mTransformType == TRANSLATION_ONLY ||
    126          !(mNativeDrawFlags & CAN_AXIS_ALIGNED_SCALE)) {
    127        mScale = MatrixScalesDouble();
    128 
    129        // Add 1 to the surface size; it's guaranteed to not be incorrect,
    130        // and it fixes bug 382458
    131        // There's probably a better fix, but I haven't figured out
    132        // the root cause of the problem.
    133        mTempSurfaceSize = IntSize((int32_t)ceil(mNativeRect.Width() + 1),
    134                                   (int32_t)ceil(mNativeRect.Height() + 1));
    135      } else {
    136        // figure out the scale factors
    137        mScale = m.ScaleFactors();
    138 
    139        mWorldTransform.eM11 = (FLOAT)mScale.xScale;
    140        mWorldTransform.eM12 = 0.0f;
    141        mWorldTransform.eM21 = 0.0f;
    142        mWorldTransform.eM22 = (FLOAT)mScale.yScale;
    143        mWorldTransform.eDx = 0.0f;
    144        mWorldTransform.eDy = 0.0f;
    145 
    146        // See comment above about "+1"
    147        mTempSurfaceSize =
    148            IntSize((int32_t)ceil(mNativeRect.Width() * mScale.xScale + 1),
    149                    (int32_t)ceil(mNativeRect.Height() * mScale.yScale + 1));
    150      }
    151    }
    152  }
    153 
    154  if (mRenderState == RENDER_STATE_NATIVE_DRAWING) {
    155    // we can just do native drawing directly to the context's surface
    156 
    157    // do we need to use SetWorldTransform?
    158    if (mTransformType != TRANSLATION_ONLY) {
    159      SetGraphicsMode(mDC, GM_ADVANCED);
    160      GetWorldTransform(mDC, &mOldWorldTransform);
    161      SetWorldTransform(mDC, &mWorldTransform);
    162    }
    163    GetViewportOrgEx(mDC, &mOrigViewportOrigin);
    164    SetViewportOrgEx(mDC, mOrigViewportOrigin.x - (int)mDeviceOffset.x,
    165                     mOrigViewportOrigin.y - (int)mDeviceOffset.y, nullptr);
    166 
    167    return mDC;
    168  } else if (mRenderState == RENDER_STATE_ALPHA_RECOVERY_BLACK ||
    169             mRenderState == RENDER_STATE_ALPHA_RECOVERY_WHITE) {
    170    // we're going to use mWinSurface to create our temporary surface here
    171 
    172    // get us a RGB24 DIB; DIB is important, because
    173    // we can later call GetImageSurface on it.
    174    mWinSurface = new gfxWindowsSurface(mTempSurfaceSize);
    175    mDC = mWinSurface->GetDC();
    176 
    177    RECT r = {0, 0, mTempSurfaceSize.width, mTempSurfaceSize.height};
    178    if (mRenderState == RENDER_STATE_ALPHA_RECOVERY_BLACK)
    179      FillRect(mDC, &r, (HBRUSH)GetStockObject(BLACK_BRUSH));
    180    else
    181      FillRect(mDC, &r, (HBRUSH)GetStockObject(WHITE_BRUSH));
    182 
    183    if ((mTransformType != TRANSLATION_ONLY) &&
    184        (mNativeDrawFlags & CAN_AXIS_ALIGNED_SCALE)) {
    185      SetGraphicsMode(mDC, GM_ADVANCED);
    186      SetWorldTransform(mDC, &mWorldTransform);
    187    }
    188 
    189    return mDC;
    190  } else {
    191    NS_ERROR("Bogus render state!");
    192    return nullptr;
    193  }
    194 }
    195 
    196 bool gfxWindowsNativeDrawing::ShouldRenderAgain() {
    197  switch (mRenderState) {
    198    case RENDER_STATE_NATIVE_DRAWING_DONE:
    199      return false;
    200 
    201    case RENDER_STATE_ALPHA_RECOVERY_BLACK_DONE:
    202      mRenderState = RENDER_STATE_ALPHA_RECOVERY_WHITE;
    203      return true;
    204 
    205    case RENDER_STATE_ALPHA_RECOVERY_WHITE_DONE:
    206      return false;
    207 
    208    default:
    209      NS_ERROR(
    210          "Invalid RenderState in gfxWindowsNativeDrawing::ShouldRenderAgain");
    211      break;
    212  }
    213 
    214  return false;
    215 }
    216 
    217 void gfxWindowsNativeDrawing::EndNativeDrawing() {
    218  if (mRenderState == RENDER_STATE_NATIVE_DRAWING) {
    219    // we drew directly to the HDC in the context; undo our changes
    220    SetViewportOrgEx(mDC, mOrigViewportOrigin.x, mOrigViewportOrigin.y,
    221                     nullptr);
    222 
    223    if (mTransformType != TRANSLATION_ONLY)
    224      SetWorldTransform(mDC, &mOldWorldTransform);
    225 
    226    mWinSurface->MarkDirty();
    227 
    228    mRenderState = RENDER_STATE_NATIVE_DRAWING_DONE;
    229  } else if (mRenderState == RENDER_STATE_ALPHA_RECOVERY_BLACK) {
    230    mBlackSurface = mWinSurface;
    231    mWinSurface = nullptr;
    232 
    233    mRenderState = RENDER_STATE_ALPHA_RECOVERY_BLACK_DONE;
    234  } else if (mRenderState == RENDER_STATE_ALPHA_RECOVERY_WHITE) {
    235    mWhiteSurface = mWinSurface;
    236    mWinSurface = nullptr;
    237 
    238    mRenderState = RENDER_STATE_ALPHA_RECOVERY_WHITE_DONE;
    239  } else {
    240    NS_ERROR(
    241        "Invalid RenderState in gfxWindowsNativeDrawing::EndNativeDrawing");
    242  }
    243 }
    244 
    245 void gfxWindowsNativeDrawing::PaintToContext() {
    246  if (mRenderState == RENDER_STATE_NATIVE_DRAWING_DONE) {
    247    // nothing to do, it already went to the context
    248    mRenderState = RENDER_STATE_DONE;
    249  } else if (mRenderState == RENDER_STATE_ALPHA_RECOVERY_WHITE_DONE) {
    250    RefPtr<gfxImageSurface> black = mBlackSurface->GetAsImageSurface();
    251    RefPtr<gfxImageSurface> white = mWhiteSurface->GetAsImageSurface();
    252    if (!gfxAlphaRecovery::RecoverAlpha(black, white)) {
    253      NS_ERROR("Alpha recovery failure");
    254      return;
    255    }
    256    RefPtr<DataSourceSurface> source = Factory::CreateWrappingDataSourceSurface(
    257        black->Data(), black->Stride(), black->GetSize(),
    258        SurfaceFormat::B8G8R8A8);
    259    {
    260      DrawTarget* dt = mContext->GetDrawTarget();
    261      AutoRestoreTransform autoRestoreTransform(dt);
    262 
    263      Matrix newTransform = dt->GetTransform();
    264      newTransform.PreTranslate(ToPoint(mNativeRect.TopLeft()));
    265      dt->SetTransform(newTransform);
    266 
    267      Rect rect(Point(0.0, 0.0), ToSize(mNativeRect.Size()));
    268      Matrix m = Matrix::Scaling(1.0 / mScale.xScale, 1.0 / mScale.yScale);
    269      SurfacePattern pat(source, ExtendMode::CLAMP, m);
    270      dt->FillRect(rect, pat);
    271    }
    272 
    273    mRenderState = RENDER_STATE_DONE;
    274  } else {
    275    NS_ERROR("Invalid RenderState in gfxWindowsNativeDrawing::PaintToContext");
    276  }
    277 }
    278 
    279 void gfxWindowsNativeDrawing::TransformToNativeRect(const gfxRect& r,
    280                                                    RECT& rout) {
    281  /* If we're doing native drawing, then we're still in the coordinate space
    282   * of the context; otherwise, we're in our own little world,
    283   * relative to the passed-in nativeRect.
    284   */
    285 
    286  gfxRect roundedRect(r);
    287 
    288  if (mRenderState == RENDER_STATE_NATIVE_DRAWING) {
    289    if (mTransformType == TRANSLATION_ONLY) {
    290      roundedRect.MoveBy(mTranslation);
    291    }
    292  } else {
    293    roundedRect.MoveBy(-mNativeRect.TopLeft());
    294  }
    295 
    296  roundedRect.Round();
    297 
    298  rout.left = LONG(roundedRect.X());
    299  rout.right = LONG(roundedRect.XMost());
    300  rout.top = LONG(roundedRect.Y());
    301  rout.bottom = LONG(roundedRect.YMost());
    302 }