image/OrientedImage.cpp

   1 /* -*- Mode: C++; tab-width: 2; 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 "OrientedImage.h"
   7
   8 #include <algorithm>
   9
  10 #include "gfx2DGlue.h"
  11 #include "gfxDrawable.h"
  12 #include "gfxPlatform.h"
  13 #include "gfxUtils.h"
  14 #include "ImageRegion.h"
  15 #include "SVGImageContext.h"
  16
  17 using std::swap;
  18
  19 namespace mozilla {
  20
  21 using namespace gfx;
  22 using layers::ImageContainer;
  23 using layers::LayerManager;
  24
  25 namespace image {
  26
  27 NS_IMETHODIMP
  28 OrientedImage::GetWidth(int32_t* aWidth) {
  29   if (mOrientation.SwapsWidthAndHeight()) {
  30     return InnerImage()->GetHeight(aWidth);
  31   } else {
  32     return InnerImage()->GetWidth(aWidth);
  33   }
  34 }
  35
  36 NS_IMETHODIMP
  37 OrientedImage::GetHeight(int32_t* aHeight) {
  38   if (mOrientation.SwapsWidthAndHeight()) {
  39     return InnerImage()->GetWidth(aHeight);
  40   } else {
  41     return InnerImage()->GetHeight(aHeight);
  42   }
  43 }
  44
  45 nsresult OrientedImage::GetNativeSizes(nsTArray<IntSize>& aNativeSizes) const {
  46   nsresult rv = InnerImage()->GetNativeSizes(aNativeSizes);
  47
  48   if (mOrientation.SwapsWidthAndHeight()) {
  49     auto i = aNativeSizes.Length();
  50     while (i > 0) {
  51       --i;
  52       swap(aNativeSizes[i].width, aNativeSizes[i].height);
  53     }
  54   }
  55
  56   return rv;
  57 }
  58
  59 NS_IMETHODIMP
  60 OrientedImage::GetIntrinsicSize(nsSize* aSize) {
  61   nsresult rv = InnerImage()->GetIntrinsicSize(aSize);
  62
  63   if (mOrientation.SwapsWidthAndHeight()) {
  64     swap(aSize->width, aSize->height);
  65   }
  66
  67   return rv;
  68 }
  69
  70 Maybe<AspectRatio> OrientedImage::GetIntrinsicRatio() {
  71   Maybe<AspectRatio> ratio = InnerImage()->GetIntrinsicRatio();
  72   if (ratio && mOrientation.SwapsWidthAndHeight()) {
  73     ratio = Some(ratio->Inverted());
  74   }
  75   return ratio;
  76 }
  77
  78 already_AddRefed<SourceSurface> OrientedImage::OrientSurface(
  79     Orientation aOrientation, SourceSurface* aSurface) {
  80   MOZ_ASSERT(aSurface);
  81
  82   // If the image does not require any re-orientation, return aSurface itself.
  83   if (aOrientation.IsIdentity()) {
  84     return do_AddRef(aSurface);
  85   }
  86
  87   // Determine the size of the new surface.
  88   nsIntSize originalSize = aSurface->GetSize();
  89   nsIntSize targetSize = originalSize;
  90   if (aOrientation.SwapsWidthAndHeight()) {
  91     swap(targetSize.width, targetSize.height);
  92   }
  93
  94   // Create our drawable.
  95   RefPtr<gfxDrawable> drawable = new gfxSurfaceDrawable(aSurface, originalSize);
  96
  97   // Determine an appropriate format for the surface.
  98   gfx::SurfaceFormat surfaceFormat = IsOpaque(aSurface->GetFormat())
  99                                          ? gfx::SurfaceFormat::OS_RGBX
 100                                          : gfx::SurfaceFormat::OS_RGBA;
 101
 102   // Create the new surface to draw into.
 103   RefPtr<DrawTarget> target =
 104       gfxPlatform::GetPlatform()->CreateOffscreenContentDrawTarget(
 105           targetSize, surfaceFormat);
 106   if (!target || !target->IsValid()) {
 107     NS_ERROR("Could not create a DrawTarget");
 108     return nullptr;
 109   }
 110
 111   // Draw.
 112   RefPtr<gfxContext> ctx = gfxContext::CreateOrNull(target);
 113   MOZ_ASSERT(ctx);  // already checked the draw target above
 114   ctx->Multiply(OrientationMatrix(aOrientation, originalSize));
 115   gfxUtils::DrawPixelSnapped(ctx, drawable, SizeDouble(originalSize),
 116                              ImageRegion::Create(originalSize), surfaceFormat,
 117                              SamplingFilter::LINEAR);
 118
 119   return target->Snapshot();
 120 }
 121
 122 NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
 123 OrientedImage::GetFrame(uint32_t aWhichFrame, uint32_t aFlags) {
 124   // Get a SourceSurface for the inner image then orient it according to
 125   // mOrientation.
 126   RefPtr<SourceSurface> innerSurface =
 127       InnerImage()->GetFrame(aWhichFrame, aFlags);
 128   NS_ENSURE_TRUE(innerSurface, nullptr);
 129
 130   return OrientSurface(mOrientation, innerSurface);
 131 }
 132
 133 NS_IMETHODIMP_(already_AddRefed<SourceSurface>)
 134 OrientedImage::GetFrameAtSize(const IntSize& aSize, uint32_t aWhichFrame,
 135                               uint32_t aFlags) {
 136   // Get a SourceSurface for the inner image then orient it according to
 137   // mOrientation.
 138   IntSize innerSize = aSize;
 139   if (mOrientation.SwapsWidthAndHeight()) {
 140     swap(innerSize.width, innerSize.height);
 141   }
 142   RefPtr<SourceSurface> innerSurface =
 143       InnerImage()->GetFrameAtSize(innerSize, aWhichFrame, aFlags);
 144   NS_ENSURE_TRUE(innerSurface, nullptr);
 145
 146   return OrientSurface(mOrientation, innerSurface);
 147 }
 148
 149 NS_IMETHODIMP_(bool)
 150 OrientedImage::IsImageContainerAvailable(LayerManager* aManager,
 151                                          uint32_t aFlags) {
 152   if (mOrientation.IsIdentity()) {
 153     return InnerImage()->IsImageContainerAvailable(aManager, aFlags);
 154   }
 155   return false;
 156 }
 157
 158 NS_IMETHODIMP_(already_AddRefed<ImageContainer>)
 159 OrientedImage::GetImageContainer(LayerManager* aManager, uint32_t aFlags) {
 160   // XXX(seth): We currently don't have a way of orienting the result of
 161   // GetImageContainer. We work around this by always returning null, but if it
 162   // ever turns out that OrientedImage is widely used on codepaths that can
 163   // actually benefit from GetImageContainer, it would be a good idea to fix
 164   // that method for performance reasons.
 165
 166   if (mOrientation.IsIdentity()) {
 167     return InnerImage()->GetImageContainer(aManager, aFlags);
 168   }
 169
 170   return nullptr;
 171 }
 172
 173 NS_IMETHODIMP_(bool)
 174 OrientedImage::IsImageContainerAvailableAtSize(LayerManager* aManager,
 175                                                const IntSize& aSize,
 176                                                uint32_t aFlags) {
 177   if (mOrientation.IsIdentity()) {
 178     return InnerImage()->IsImageContainerAvailableAtSize(aManager, aSize,
 179                                                          aFlags);
 180   }
 181   return false;
 182 }
 183
 184 NS_IMETHODIMP_(ImgDrawResult)
 185 OrientedImage::GetImageContainerAtSize(
 186     layers::LayerManager* aManager, const gfx::IntSize& aSize,
 187     const Maybe<SVGImageContext>& aSVGContext, uint32_t aFlags,
 188     layers::ImageContainer** aOutContainer) {
 189   // XXX(seth): We currently don't have a way of orienting the result of
 190   // GetImageContainer. We work around this by always returning null, but if it
 191   // ever turns out that OrientedImage is widely used on codepaths that can
 192   // actually benefit from GetImageContainer, it would be a good idea to fix
 193   // that method for performance reasons.
 194
 195   if (mOrientation.IsIdentity()) {
 196     return InnerImage()->GetImageContainerAtSize(aManager, aSize, aSVGContext,
 197                                                  aFlags, aOutContainer);
 198   }
 199
 200   return ImgDrawResult::NOT_SUPPORTED;
 201 }
 202
 203 struct MatrixBuilder {
 204   explicit MatrixBuilder(bool aInvert) : mInvert(aInvert) {}
 205
 206   gfxMatrix Build() { return mMatrix; }
 207
 208   void Scale(gfxFloat aX, gfxFloat aY) {
 209     if (mInvert) {
 210       mMatrix *= gfxMatrix::Scaling(1.0 / aX, 1.0 / aY);
 211     } else {
 212       mMatrix.PreScale(aX, aY);
 213     }
 214   }
 215
 216   void Rotate(gfxFloat aPhi) {
 217     if (mInvert) {
 218       mMatrix *= gfxMatrix::Rotation(-aPhi);
 219     } else {
 220       mMatrix.PreRotate(aPhi);
 221     }
 222   }
 223
 224   void Translate(gfxPoint aDelta) {
 225     if (mInvert) {
 226       mMatrix *= gfxMatrix::Translation(-aDelta);
 227     } else {
 228       mMatrix.PreTranslate(aDelta);
 229     }
 230   }
 231
 232  private:
 233   gfxMatrix mMatrix;
 234   bool mInvert;
 235 };
 236
 237 gfxMatrix OrientedImage::OrientationMatrix(Orientation aOrientation,
 238                                            const nsIntSize& aSize,
 239                                            bool aInvert /* = false */) {
 240   MatrixBuilder builder(aInvert);
 241
 242   // Apply reflection, if present. (For a regular, non-flipFirst reflection,
 243   // this logically happens second, but we apply it first because these
 244   // transformations are all premultiplied.) A translation is necessary to place
 245   // the image back in the first quadrant.
 246   if (aOrientation.flip == Flip::Horizontal && !aOrientation.flipFirst) {
 247     if (aOrientation.SwapsWidthAndHeight()) {
 248       builder.Translate(gfxPoint(aSize.height, 0));
 249     } else {
 250       builder.Translate(gfxPoint(aSize.width, 0));
 251     }
 252     builder.Scale(-1.0, 1.0);
 253   }
 254
 255   // Apply rotation, if present. Again, a translation is used to place the
 256   // image back in the first quadrant.
 257   switch (aOrientation.rotation) {
 258     case Angle::D0:
 259       break;
 260     case Angle::D90:
 261       builder.Translate(gfxPoint(aSize.height, 0));
 262       builder.Rotate(-1.5 * M_PI);
 263       break;
 264     case Angle::D180:
 265       builder.Translate(gfxPoint(aSize.width, aSize.height));
 266       builder.Rotate(-1.0 * M_PI);
 267       break;
 268     case Angle::D270:
 269       builder.Translate(gfxPoint(0, aSize.width));
 270       builder.Rotate(-0.5 * M_PI);
 271       break;
 272     default:
 273       MOZ_ASSERT(false, "Invalid rotation value");
 274   }
 275
 276   // Apply a flipFirst reflection.
 277   if (aOrientation.flip == Flip::Horizontal && aOrientation.flipFirst) {
 278     builder.Translate(gfxPoint(aSize.width, 0.0));
 279     builder.Scale(-1.0, 1.0);
 280   }
 281
 282   return builder.Build();
 283 }
 284
 285 NS_IMETHODIMP_(ImgDrawResult)
 286 OrientedImage::Draw(gfxContext* aContext, const nsIntSize& aSize,
 287                     const ImageRegion& aRegion, uint32_t aWhichFrame,
 288                     SamplingFilter aSamplingFilter,
 289                     const Maybe<SVGImageContext>& aSVGContext, uint32_t aFlags,
 290                     float aOpacity) {
 291   if (mOrientation.IsIdentity()) {
 292     return InnerImage()->Draw(aContext, aSize, aRegion, aWhichFrame,
 293                               aSamplingFilter, aSVGContext, aFlags, aOpacity);
 294   }
 295
 296   // Update the image size to match the image's coordinate system. (This could
 297   // be done using TransformBounds but since it's only a size a swap is enough.)
 298   nsIntSize size(aSize);
 299   if (mOrientation.SwapsWidthAndHeight()) {
 300     swap(size.width, size.height);
 301   }
 302
 303   // Update the matrix so that we transform the image into the orientation
 304   // expected by the caller before drawing.
 305   gfxMatrix matrix(OrientationMatrix(size));
 306   gfxContextMatrixAutoSaveRestore saveMatrix(aContext);
 307   aContext->Multiply(matrix);
 308
 309   // The region is already in the orientation expected by the caller, but we
 310   // need it to be in the image's coordinate system, so we transform it using
 311   // the inverse of the orientation matrix.
 312   gfxMatrix inverseMatrix(OrientationMatrix(size, /* aInvert = */ true));
 313   ImageRegion region(aRegion);
 314   region.TransformBoundsBy(inverseMatrix);
 315
 316   auto orientViewport = [&](const SVGImageContext& aOldContext) {
 317     SVGImageContext context(aOldContext);
 318     auto oldViewport = aOldContext.GetViewportSize();
 319     if (oldViewport && mOrientation.SwapsWidthAndHeight()) {
 320       // Swap width and height:
 321       CSSIntSize newViewport(oldViewport->height, oldViewport->width);
 322       context.SetViewportSize(Some(newViewport));
 323     }
 324     return context;
 325   };
 326
 327   return InnerImage()->Draw(aContext, size, region, aWhichFrame,
 328                             aSamplingFilter, aSVGContext.map(orientViewport),
 329                             aFlags, aOpacity);
 330 }
 331
 332 nsIntSize OrientedImage::OptimalImageSizeForDest(const gfxSize& aDest,
 333                                                  uint32_t aWhichFrame,
 334                                                  SamplingFilter aSamplingFilter,
 335                                                  uint32_t aFlags) {
 336   if (!mOrientation.SwapsWidthAndHeight()) {
 337     return InnerImage()->OptimalImageSizeForDest(aDest, aWhichFrame,
 338                                                  aSamplingFilter, aFlags);
 339   }
 340
 341   // Swap the size for the calculation, then swap it back for the caller.
 342   gfxSize destSize(aDest.height, aDest.width);
 343   nsIntSize innerImageSize(InnerImage()->OptimalImageSizeForDest(
 344       destSize, aWhichFrame, aSamplingFilter, aFlags));
 345   return nsIntSize(innerImageSize.height, innerImageSize.width);
 346 }
 347
 348 NS_IMETHODIMP_(nsIntRect)
 349 OrientedImage::GetImageSpaceInvalidationRect(const nsIntRect& aRect) {
 350   nsIntRect rect(InnerImage()->GetImageSpaceInvalidationRect(aRect));
 351
 352   if (mOrientation.IsIdentity()) {
 353     return rect;
 354   }
 355
 356   nsIntSize innerSize;
 357   nsresult rv = InnerImage()->GetWidth(&innerSize.width);
 358   rv = NS_FAILED(rv) ? rv : InnerImage()->GetHeight(&innerSize.height);
 359   if (NS_FAILED(rv)) {
 360     // Fall back to identity if the width and height aren't available.
 361     return rect;
 362   }
 363
 364   // Transform the invalidation rect into the correct orientation.
 365   gfxMatrix matrix(OrientationMatrix(innerSize));
 366   gfxRect invalidRect(matrix.TransformBounds(
 367       gfxRect(rect.X(), rect.Y(), rect.Width(), rect.Height())));
 368
 369   return IntRect::RoundOut(invalidRect.X(), invalidRect.Y(),
 370                            invalidRect.Width(), invalidRect.Height());
 371 }
 372
 373 }  // namespace image
 374 }  // namespace mozilla