michael@0: /* -*- Mode: C++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
michael@0: /* This Source Code Form is subject to the terms of the Mozilla Public
michael@0:  * License, v. 2.0. If a copy of the MPL was not distributed with this
michael@0:  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
michael@0: 
michael@0: // Main header first:
michael@0: #include "nsSVGMaskFrame.h"
michael@0: 
michael@0: // Keep others in (case-insensitive) order:
michael@0: #include "gfxContext.h"
michael@0: #include "gfxImageSurface.h"
michael@0: #include "nsRenderingContext.h"
michael@0: #include "nsSVGEffects.h"
michael@0: #include "mozilla/dom/SVGMaskElement.h"
michael@0: 
michael@0: using namespace mozilla::dom;
michael@0: 
michael@0: /**
michael@0:  * Byte offsets of channels in a native packed gfxColor or cairo image surface.
michael@0:  */
michael@0: #ifdef IS_BIG_ENDIAN
michael@0: #define GFX_ARGB32_OFFSET_A 0
michael@0: #define GFX_ARGB32_OFFSET_R 1
michael@0: #define GFX_ARGB32_OFFSET_G 2
michael@0: #define GFX_ARGB32_OFFSET_B 3
michael@0: #else
michael@0: #define GFX_ARGB32_OFFSET_A 3
michael@0: #define GFX_ARGB32_OFFSET_R 2
michael@0: #define GFX_ARGB32_OFFSET_G 1
michael@0: #define GFX_ARGB32_OFFSET_B 0
michael@0: #endif
michael@0: 
michael@0: // c = n / 255
michael@0: // c <= 0.04045 ? c / 12.92 : pow((c + 0.055) / 1.055, 2.4)) * 255 + 0.5
michael@0: static const uint8_t gsRGBToLinearRGBMap[256] = {
michael@0:   0,   0,   0,   0,   0,   0,   0,   1,
michael@0:   1,   1,   1,   1,   1,   1,   1,   1,
michael@0:   1,   1,   2,   2,   2,   2,   2,   2,
michael@0:   2,   2,   3,   3,   3,   3,   3,   3,
michael@0:   4,   4,   4,   4,   4,   5,   5,   5,
michael@0:   5,   6,   6,   6,   6,   7,   7,   7,
michael@0:   8,   8,   8,   8,   9,   9,   9,  10,
michael@0:  10,  10,  11,  11,  12,  12,  12,  13,
michael@0:  13,  13,  14,  14,  15,  15,  16,  16,
michael@0:  17,  17,  17,  18,  18,  19,  19,  20,
michael@0:  20,  21,  22,  22,  23,  23,  24,  24,
michael@0:  25,  25,  26,  27,  27,  28,  29,  29,
michael@0:  30,  30,  31,  32,  32,  33,  34,  35,
michael@0:  35,  36,  37,  37,  38,  39,  40,  41,
michael@0:  41,  42,  43,  44,  45,  45,  46,  47,
michael@0:  48,  49,  50,  51,  51,  52,  53,  54,
michael@0:  55,  56,  57,  58,  59,  60,  61,  62,
michael@0:  63,  64,  65,  66,  67,  68,  69,  70,
michael@0:  71,  72,  73,  74,  76,  77,  78,  79,
michael@0:  80,  81,  82,  84,  85,  86,  87,  88,
michael@0:  90,  91,  92,  93,  95,  96,  97,  99,
michael@0: 100, 101, 103, 104, 105, 107, 108, 109,
michael@0: 111, 112, 114, 115, 116, 118, 119, 121,
michael@0: 122, 124, 125, 127, 128, 130, 131, 133,
michael@0: 134, 136, 138, 139, 141, 142, 144, 146,
michael@0: 147, 149, 151, 152, 154, 156, 157, 159,
michael@0: 161, 163, 164, 166, 168, 170, 171, 173,
michael@0: 175, 177, 179, 181, 183, 184, 186, 188,
michael@0: 190, 192, 194, 196, 198, 200, 202, 204,
michael@0: 206, 208, 210, 212, 214, 216, 218, 220,
michael@0: 222, 224, 226, 229, 231, 233, 235, 237,
michael@0: 239, 242, 244, 246, 248, 250, 253, 255
michael@0: };
michael@0: 
michael@0: static void
michael@0: ComputesRGBLuminanceMask(uint8_t *aData,
michael@0:                          int32_t aStride,
michael@0:                          const nsIntRect &aRect,
michael@0:                          float aOpacity)
michael@0: {
michael@0:   for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
michael@0:     for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
michael@0:       uint8_t *pixel = aData + aStride * y + 4 * x;
michael@0:       uint8_t a = pixel[GFX_ARGB32_OFFSET_A];
michael@0: 
michael@0:       uint8_t luminance;
michael@0:       if (a) {
michael@0:         /* sRGB -> intensity (unpremultiply cancels out the
michael@0:          * (a/255.0) multiplication with aOpacity */
michael@0:         luminance =
michael@0:           static_cast<uint8_t>
michael@0:                      ((pixel[GFX_ARGB32_OFFSET_R] * 0.2125 +
michael@0:                        pixel[GFX_ARGB32_OFFSET_G] * 0.7154 +
michael@0:                        pixel[GFX_ARGB32_OFFSET_B] * 0.0721) *
michael@0:                       aOpacity);
michael@0:       } else {
michael@0:         luminance = 0;
michael@0:       }
michael@0:       memset(pixel, luminance, 4);
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: static void
michael@0: ComputeLinearRGBLuminanceMask(uint8_t *aData,
michael@0:                               int32_t aStride,
michael@0:                               const nsIntRect &aRect,
michael@0:                               float aOpacity)
michael@0: {
michael@0:   for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
michael@0:     for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
michael@0:       uint8_t *pixel = aData + aStride * y + 4 * x;
michael@0:       uint8_t a = pixel[GFX_ARGB32_OFFSET_A];
michael@0: 
michael@0:       uint8_t luminance;
michael@0:       // unpremultiply
michael@0:       if (a) {
michael@0:         if (a != 255) {
michael@0:           pixel[GFX_ARGB32_OFFSET_B] =
michael@0:             (255 * pixel[GFX_ARGB32_OFFSET_B]) / a;
michael@0:           pixel[GFX_ARGB32_OFFSET_G] =
michael@0:             (255 * pixel[GFX_ARGB32_OFFSET_G]) / a;
michael@0:           pixel[GFX_ARGB32_OFFSET_R] =
michael@0:             (255 * pixel[GFX_ARGB32_OFFSET_R]) / a;
michael@0:         }
michael@0: 
michael@0:         /* sRGB -> linearRGB -> intensity */
michael@0:         luminance =
michael@0:           static_cast<uint8_t>
michael@0:                      ((gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_R]] *
michael@0:                        0.2125 +
michael@0:                        gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_G]] *
michael@0:                        0.7154 +
michael@0:                        gsRGBToLinearRGBMap[pixel[GFX_ARGB32_OFFSET_B]] *
michael@0:                        0.0721) * (a / 255.0) * aOpacity);
michael@0:       } else {
michael@0:         luminance = 0;
michael@0:       }
michael@0:       memset(pixel, luminance, 4);
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: static void
michael@0: ComputeAlphaMask(uint8_t *aData,
michael@0:                  int32_t aStride,
michael@0:                  const nsIntRect &aRect,
michael@0:                  float aOpacity)
michael@0: {
michael@0:   for (int32_t y = aRect.y; y < aRect.YMost(); y++) {
michael@0:     for (int32_t x = aRect.x; x < aRect.XMost(); x++) {
michael@0:       uint8_t *pixel = aData + aStride * y + 4 * x;
michael@0:       uint8_t luminance = pixel[GFX_ARGB32_OFFSET_A] * aOpacity;
michael@0:       memset(pixel, luminance, 4);
michael@0:     }
michael@0:   }
michael@0: }
michael@0: 
michael@0: //----------------------------------------------------------------------
michael@0: // Implementation
michael@0: 
michael@0: nsIFrame*
michael@0: NS_NewSVGMaskFrame(nsIPresShell* aPresShell, nsStyleContext* aContext)
michael@0: {
michael@0:   return new (aPresShell) nsSVGMaskFrame(aContext);
michael@0: }
michael@0: 
michael@0: NS_IMPL_FRAMEARENA_HELPERS(nsSVGMaskFrame)
michael@0: 
michael@0: already_AddRefed<gfxPattern>
michael@0: nsSVGMaskFrame::ComputeMaskAlpha(nsRenderingContext *aContext,
michael@0:                                  nsIFrame* aParent,
michael@0:                                  const gfxMatrix &aMatrix,
michael@0:                                  float aOpacity)
michael@0: {
michael@0:   // If the flag is set when we get here, it means this mask frame
michael@0:   // has already been used painting the current mask, and the document
michael@0:   // has a mask reference loop.
michael@0:   if (mInUse) {
michael@0:     NS_WARNING("Mask loop detected!");
michael@0:     return nullptr;
michael@0:   }
michael@0:   AutoMaskReferencer maskRef(this);
michael@0: 
michael@0:   SVGMaskElement *mask = static_cast<SVGMaskElement*>(mContent);
michael@0: 
michael@0:   uint16_t units =
michael@0:     mask->mEnumAttributes[SVGMaskElement::MASKUNITS].GetAnimValue();
michael@0:   gfxRect bbox;
michael@0:   if (units == SVG_UNIT_TYPE_OBJECTBOUNDINGBOX) {
michael@0:     bbox = nsSVGUtils::GetBBox(aParent);
michael@0:   }
michael@0: 
michael@0:   gfxRect maskArea = nsSVGUtils::GetRelativeRect(units,
michael@0:     &mask->mLengthAttributes[SVGMaskElement::ATTR_X], bbox, aParent);
michael@0: 
michael@0:   gfxContext *gfx = aContext->ThebesContext();
michael@0: 
michael@0:   // Get the clip extents in device space:
michael@0:   gfx->Save();
michael@0:   nsSVGUtils::SetClipRect(gfx, aMatrix, maskArea);
michael@0:   gfx->IdentityMatrix();
michael@0:   gfxRect clipExtents = gfx->GetClipExtents();
michael@0:   clipExtents.RoundOut();
michael@0:   gfx->Restore();
michael@0: 
michael@0:   bool resultOverflows;
michael@0:   gfxIntSize surfaceSize =
michael@0:     nsSVGUtils::ConvertToSurfaceSize(gfxSize(clipExtents.Width(),
michael@0:                                              clipExtents.Height()),
michael@0:                                      &resultOverflows);
michael@0: 
michael@0:   // 0 disables mask, < 0 is an error
michael@0:   if (surfaceSize.width <= 0 || surfaceSize.height <= 0)
michael@0:     return nullptr;
michael@0: 
michael@0:   if (resultOverflows)
michael@0:     return nullptr;
michael@0: 
michael@0:   nsRefPtr<gfxImageSurface> image =
michael@0:     new gfxImageSurface(surfaceSize, gfxImageFormat::ARGB32);
michael@0:   if (!image || image->CairoStatus())
michael@0:     return nullptr;
michael@0: 
michael@0:   // We would like to use gfxImageSurface::SetDeviceOffset() to position
michael@0:   // 'image'. However, we need to set the same matrix on the temporary context
michael@0:   // and pattern that we create below as is currently set on 'gfx'.
michael@0:   // Unfortunately, any device offset set by SetDeviceOffset() is affected by
michael@0:   // the transform passed to the SetMatrix() calls, so to avoid that we account
michael@0:   // for the device offset in the transform rather than use SetDeviceOffset().
michael@0:   gfxMatrix matrix =
michael@0:     gfx->CurrentMatrix() * gfxMatrix().Translate(-clipExtents.TopLeft());
michael@0: 
michael@0:   nsRefPtr<nsRenderingContext> tmpCtx(new nsRenderingContext);
michael@0:   tmpCtx->Init(this->PresContext()->DeviceContext(), image);
michael@0:   tmpCtx->ThebesContext()->SetMatrix(matrix);
michael@0: 
michael@0:   mMaskParent = aParent;
michael@0:   if (mMaskParentMatrix) {
michael@0:     *mMaskParentMatrix = aMatrix;
michael@0:   } else {
michael@0:     mMaskParentMatrix = new gfxMatrix(aMatrix);
michael@0:   }
michael@0: 
michael@0:   for (nsIFrame* kid = mFrames.FirstChild(); kid;
michael@0:        kid = kid->GetNextSibling()) {
michael@0:     // The CTM of each frame referencing us can be different
michael@0:     nsISVGChildFrame* SVGFrame = do_QueryFrame(kid);
michael@0:     if (SVGFrame) {
michael@0:       SVGFrame->NotifySVGChanged(nsISVGChildFrame::TRANSFORM_CHANGED);
michael@0:     }
michael@0:     nsSVGUtils::PaintFrameWithEffects(tmpCtx, nullptr, kid);
michael@0:   }
michael@0: 
michael@0:   uint8_t *data   = image->Data();
michael@0:   int32_t  stride = image->Stride();
michael@0:   nsIntRect rect(0, 0, surfaceSize.width, surfaceSize.height);
michael@0: 
michael@0:   if (StyleSVGReset()->mMaskType == NS_STYLE_MASK_TYPE_LUMINANCE) {
michael@0:     if (StyleSVG()->mColorInterpolation ==
michael@0:         NS_STYLE_COLOR_INTERPOLATION_LINEARRGB) {
michael@0:       ComputeLinearRGBLuminanceMask(data, stride, rect, aOpacity);
michael@0:     } else {
michael@0:       ComputesRGBLuminanceMask(data, stride, rect, aOpacity);
michael@0:     }
michael@0:   } else {
michael@0:     ComputeAlphaMask(data, stride, rect, aOpacity);
michael@0:   }
michael@0: 
michael@0:   nsRefPtr<gfxPattern> retval = new gfxPattern(image);
michael@0:   retval->SetMatrix(matrix);
michael@0:   return retval.forget();
michael@0: }
michael@0: 
michael@0: nsresult
michael@0: nsSVGMaskFrame::AttributeChanged(int32_t  aNameSpaceID,
michael@0:                                  nsIAtom* aAttribute,
michael@0:                                  int32_t  aModType)
michael@0: {
michael@0:   if (aNameSpaceID == kNameSpaceID_None &&
michael@0:       (aAttribute == nsGkAtoms::x ||
michael@0:        aAttribute == nsGkAtoms::y ||
michael@0:        aAttribute == nsGkAtoms::width ||
michael@0:        aAttribute == nsGkAtoms::height||
michael@0:        aAttribute == nsGkAtoms::maskUnits ||
michael@0:        aAttribute == nsGkAtoms::maskContentUnits)) {
michael@0:     nsSVGEffects::InvalidateDirectRenderingObservers(this);
michael@0:   }
michael@0: 
michael@0:   return nsSVGMaskFrameBase::AttributeChanged(aNameSpaceID,
michael@0:                                               aAttribute, aModType);
michael@0: }
michael@0: 
michael@0: #ifdef DEBUG
michael@0: void
michael@0: nsSVGMaskFrame::Init(nsIContent* aContent,
michael@0:                      nsIFrame* aParent,
michael@0:                      nsIFrame* aPrevInFlow)
michael@0: {
michael@0:   NS_ASSERTION(aContent->IsSVG(nsGkAtoms::mask),
michael@0:                "Content is not an SVG mask");
michael@0: 
michael@0:   nsSVGMaskFrameBase::Init(aContent, aParent, aPrevInFlow);
michael@0: }
michael@0: #endif /* DEBUG */
michael@0: 
michael@0: nsIAtom *
michael@0: nsSVGMaskFrame::GetType() const
michael@0: {
michael@0:   return nsGkAtoms::svgMaskFrame;
michael@0: }
michael@0: 
michael@0: gfxMatrix
michael@0: nsSVGMaskFrame::GetCanvasTM(uint32_t aFor, nsIFrame* aTransformRoot)
michael@0: {
michael@0:   NS_ASSERTION(mMaskParentMatrix, "null parent matrix");
michael@0: 
michael@0:   SVGMaskElement *mask = static_cast<SVGMaskElement*>(mContent);
michael@0: 
michael@0:   return nsSVGUtils::AdjustMatrixForUnits(
michael@0:     mMaskParentMatrix ? *mMaskParentMatrix : gfxMatrix(),
michael@0:     &mask->mEnumAttributes[SVGMaskElement::MASKCONTENTUNITS],
michael@0:     mMaskParent);
michael@0: }
michael@0: