| /* |
| * Copyright (C) 2020 Apple Inc. All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * 1. Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * 2. Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * |
| * THIS SOFTWARE IS PROVIDED BY APPLE INC. AND ITS CONTRIBUTORS ``AS IS'' |
| * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, |
| * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL APPLE INC. OR ITS CONTRIBUTORS |
| * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF |
| * THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include "config.h" |
| #include "DisplayFillLayerImageGeometry.h" |
| |
| #if ENABLE(LAYOUT_FORMATTING_CONTEXT) |
| |
| #include "DisplayBox.h" |
| #include "FillLayer.h" |
| #include "LayoutBox.h" |
| #include "LayoutBoxGeometry.h" |
| #include "LengthFunctions.h" |
| #include "RenderStyle.h" |
| |
| namespace WebCore { |
| namespace Display { |
| |
| static inline LayoutUnit resolveWidthForRatio(LayoutUnit height, const LayoutSize& intrinsicRatio) |
| { |
| return height * intrinsicRatio.width() / intrinsicRatio.height(); |
| } |
| |
| static inline LayoutUnit resolveHeightForRatio(LayoutUnit width, const LayoutSize& intrinsicRatio) |
| { |
| return width * intrinsicRatio.height() / intrinsicRatio.width(); |
| } |
| |
| static inline LayoutSize resolveAgainstIntrinsicWidthOrHeightAndRatio(LayoutSize size, LayoutSize intrinsicRatio, LayoutUnit useWidth, LayoutUnit useHeight) |
| { |
| if (intrinsicRatio.isEmpty()) { |
| if (useWidth) |
| return LayoutSize(useWidth, size.height()); |
| |
| return LayoutSize(size.width(), useHeight); |
| } |
| |
| if (useWidth) |
| return LayoutSize(useWidth, resolveHeightForRatio(useWidth, intrinsicRatio)); |
| |
| return LayoutSize(resolveWidthForRatio(useHeight, intrinsicRatio), useHeight); |
| } |
| |
| static inline LayoutSize resolveAgainstIntrinsicRatio(LayoutSize size, const LayoutSize& intrinsicRatio) |
| { |
| // Two possible solutions: (size.width(), solutionHeight) or (solutionWidth, size.height()) |
| // "... must be assumed to be the largest dimensions..." = easiest answer: the rect with the largest surface area. |
| |
| LayoutUnit solutionWidth = resolveWidthForRatio(size.height(), intrinsicRatio); |
| LayoutUnit solutionHeight = resolveHeightForRatio(size.width(), intrinsicRatio); |
| if (solutionWidth <= size.width()) { |
| if (solutionHeight <= size.height()) { |
| // If both solutions fit, choose the one covering the larger area. |
| LayoutUnit areaOne = solutionWidth * size.height(); |
| LayoutUnit areaTwo = size.width() * solutionHeight; |
| if (areaOne < areaTwo) |
| return LayoutSize(size.width(), solutionHeight); |
| |
| return LayoutSize(solutionWidth, size.height()); |
| } |
| |
| // Only the first solution fits. |
| return LayoutSize(solutionWidth, size.height()); |
| } |
| |
| // Only the second solution fits, assert that. |
| ASSERT(solutionHeight <= size.height()); |
| return LayoutSize(size.width(), solutionHeight); |
| } |
| |
| static LayoutSize calculateImageIntrinsicDimensions(StyleImage* image, LayoutSize positioningAreaSize) |
| { |
| // A generated image without a fixed size, will always return the container size as intrinsic size. |
| if (image->isGeneratedImage() && image->usesImageContainerSize()) |
| return LayoutSize(positioningAreaSize.width(), positioningAreaSize.height()); |
| |
| // FIXME: Call computeIntrinsicDimensions(). |
| auto imageSize = image->imageSize(nullptr, 1); |
| auto intrinsicRatio = imageSize; |
| Length intrinsicWidth = Length(intrinsicRatio.width(), LengthType::Fixed); |
| Length intrinsicHeight = Length(intrinsicRatio.height(), LengthType::Fixed); |
| |
| ASSERT(!intrinsicWidth.isPercentOrCalculated()); |
| ASSERT(!intrinsicHeight.isPercentOrCalculated()); |
| |
| LayoutSize resolvedSize(intrinsicWidth.value(), intrinsicHeight.value()); |
| LayoutSize minimumSize(resolvedSize.width() > 0 ? 1 : 0, resolvedSize.height() > 0 ? 1 : 0); |
| |
| // FIXME: Respect ScaleByEffectiveZoom. |
| resolvedSize.clampToMinimumSize(minimumSize); |
| |
| if (!resolvedSize.isEmpty()) |
| return resolvedSize; |
| |
| // If the image has one of either an intrinsic width or an intrinsic height: |
| // * and an intrinsic aspect ratio, then the missing dimension is calculated from the given dimension and the ratio. |
| // * and no intrinsic aspect ratio, then the missing dimension is assumed to be the size of the rectangle that |
| // establishes the coordinate system for the 'background-position' property. |
| if (resolvedSize.width() > 0 || resolvedSize.height() > 0) |
| return resolveAgainstIntrinsicWidthOrHeightAndRatio(positioningAreaSize, LayoutSize(intrinsicRatio), resolvedSize.width(), resolvedSize.height()); |
| |
| // If the image has no intrinsic dimensions and has an intrinsic ratio the dimensions must be assumed to be the |
| // largest dimensions at that ratio such that neither dimension exceeds the dimensions of the rectangle that |
| // establishes the coordinate system for the 'background-position' property. |
| if (!intrinsicRatio.isEmpty()) |
| return resolveAgainstIntrinsicRatio(positioningAreaSize, LayoutSize(intrinsicRatio)); |
| |
| // If the image has no intrinsic ratio either, then the dimensions must be assumed to be the rectangle that |
| // establishes the coordinate system for the 'background-position' property. |
| return positioningAreaSize; |
| } |
| |
| static LayoutSize calculateFillTileSize(const FillLayer& fillLayer, LayoutSize positioningAreaSize, float pixelSnappingFactor) |
| { |
| StyleImage* image = fillLayer.image(); |
| FillSizeType type = fillLayer.size().type; |
| auto devicePixelSize = LayoutUnit { 1.0 / pixelSnappingFactor }; |
| |
| LayoutSize imageIntrinsicSize; |
| if (image) { |
| imageIntrinsicSize = calculateImageIntrinsicDimensions(image, positioningAreaSize); |
| imageIntrinsicSize.scale(1 / image->imageScaleFactor(), 1 / image->imageScaleFactor()); |
| } else |
| imageIntrinsicSize = positioningAreaSize; |
| |
| switch (type) { |
| case FillSizeType::Size: { |
| LayoutSize tileSize = positioningAreaSize; |
| |
| Length layerWidth = fillLayer.size().size.width; |
| Length layerHeight = fillLayer.size().size.height; |
| |
| if (layerWidth.isFixed()) |
| tileSize.setWidth(layerWidth.value()); |
| else if (layerWidth.isPercentOrCalculated()) { |
| auto resolvedWidth = valueForLength(layerWidth, positioningAreaSize.width()); |
| // Non-zero resolved value should always produce some content. |
| tileSize.setWidth(!resolvedWidth ? resolvedWidth : std::max(devicePixelSize, resolvedWidth)); |
| } |
| |
| if (layerHeight.isFixed()) |
| tileSize.setHeight(layerHeight.value()); |
| else if (layerHeight.isPercentOrCalculated()) { |
| auto resolvedHeight = valueForLength(layerHeight, positioningAreaSize.height()); |
| // Non-zero resolved value should always produce some content. |
| tileSize.setHeight(!resolvedHeight ? resolvedHeight : std::max(devicePixelSize, resolvedHeight)); |
| } |
| |
| // If one of the values is auto we have to use the appropriate |
| // scale to maintain our aspect ratio. |
| if (layerWidth.isAuto() && !layerHeight.isAuto()) { |
| if (imageIntrinsicSize.height()) |
| tileSize.setWidth(imageIntrinsicSize.width() * tileSize.height() / imageIntrinsicSize.height()); |
| } else if (!layerWidth.isAuto() && layerHeight.isAuto()) { |
| if (imageIntrinsicSize.width()) |
| tileSize.setHeight(imageIntrinsicSize.height() * tileSize.width() / imageIntrinsicSize.width()); |
| } else if (layerWidth.isAuto() && layerHeight.isAuto()) { |
| // If both width and height are auto, use the image's intrinsic size. |
| tileSize = imageIntrinsicSize; |
| } |
| |
| tileSize.clampNegativeToZero(); |
| return tileSize; |
| } |
| case FillSizeType::None: { |
| // If both values are ‘auto’ then the intrinsic width and/or height of the image should be used, if any. |
| if (!imageIntrinsicSize.isEmpty()) |
| return imageIntrinsicSize; |
| |
| // If the image has neither an intrinsic width nor an intrinsic height, its size is determined as for ‘contain’. |
| type = FillSizeType::Contain; |
| } |
| FALLTHROUGH; |
| case FillSizeType::Contain: |
| case FillSizeType::Cover: { |
| // Scale computation needs higher precision than what LayoutUnit can offer. |
| FloatSize localImageIntrinsicSize = imageIntrinsicSize; |
| FloatSize localPositioningAreaSize = positioningAreaSize; |
| |
| float horizontalScaleFactor = localImageIntrinsicSize.width() ? (localPositioningAreaSize.width() / localImageIntrinsicSize.width()) : 1; |
| float verticalScaleFactor = localImageIntrinsicSize.height() ? (localPositioningAreaSize.height() / localImageIntrinsicSize.height()) : 1; |
| float scaleFactor = type == FillSizeType::Contain ? std::min(horizontalScaleFactor, verticalScaleFactor) : std::max(horizontalScaleFactor, verticalScaleFactor); |
| |
| if (localImageIntrinsicSize.isEmpty()) |
| return { }; |
| |
| return LayoutSize(localImageIntrinsicSize.scaled(scaleFactor).expandedTo({ devicePixelSize, devicePixelSize })); |
| } |
| } |
| |
| ASSERT_NOT_REACHED(); |
| return { }; |
| } |
| |
| static inline LayoutUnit getSpace(LayoutUnit areaSize, LayoutUnit tileSize) |
| { |
| int numberOfTiles = areaSize / tileSize; |
| LayoutUnit space = -1; |
| |
| if (numberOfTiles > 1) |
| space = (areaSize - numberOfTiles * tileSize) / (numberOfTiles - 1); |
| |
| return space; |
| } |
| |
| static LayoutUnit resolveEdgeRelativeLength(const Length& length, Edge edge, LayoutUnit availableSpace, const LayoutSize& areaSize, const LayoutSize& tileSize) |
| { |
| LayoutUnit result = minimumValueForLength(length, availableSpace); |
| |
| if (edge == Edge::Right) |
| return areaSize.width() - tileSize.width() - result; |
| |
| if (edge == Edge::Bottom) |
| return areaSize.height() - tileSize.height() - result; |
| |
| return result; |
| } |
| |
| static FillLayerImageGeometry pixelSnappedFillLayerImageGeometry(LayoutRect& destinationRect, LayoutSize& tileSize, LayoutSize& phase, LayoutSize& space, FillAttachment attachment, float pixelSnappingFactor) |
| { |
| return FillLayerImageGeometry { |
| snapRectToDevicePixels(destinationRect, pixelSnappingFactor), |
| snapRectToDevicePixels({ destinationRect.location(), tileSize }, pixelSnappingFactor).size(), |
| snapRectToDevicePixels({ destinationRect.location(), phase }, pixelSnappingFactor).size(), |
| snapRectToDevicePixels({ { }, space }, pixelSnappingFactor).size(), |
| attachment |
| }; |
| } |
| |
| static FillLayerImageGeometry geometryForLayer(const FillLayer& fillLayer, LayoutRect borderBoxRect, const Layout::BoxGeometry& geometry, float pixelSnappingFactor) |
| { |
| LayoutUnit left; |
| LayoutUnit top; |
| LayoutSize positioningAreaSize; |
| |
| auto destinationRect = borderBoxRect; |
| |
| switch (fillLayer.attachment()) { |
| case FillAttachment::ScrollBackground: |
| case FillAttachment::LocalBackground: { |
| LayoutUnit right; |
| LayoutUnit bottom; |
| if (fillLayer.origin() != FillBox::Border) { |
| left = geometry.borderLeft(); |
| right = geometry.borderRight(); |
| top = geometry.borderTop(); |
| bottom = geometry.borderBottom(); |
| if (fillLayer.origin() == FillBox::Content) { |
| left += geometry.paddingLeft().value_or(0); |
| right += geometry.paddingRight().value_or(0); |
| top += geometry.paddingTop().value_or(0); |
| bottom += geometry.paddingBottom().value_or(0); |
| } |
| } |
| |
| // FIXME: Handle the root element sizing. |
| positioningAreaSize = borderBoxRect.size() - LayoutSize(left + right, top + bottom); |
| break; |
| } |
| case FillAttachment::FixedBackground: { |
| // FIXME: Handle fixed backgrounds. |
| positioningAreaSize = borderBoxRect.size(); |
| break; |
| } |
| } |
| |
| LayoutSize tileSize = calculateFillTileSize(fillLayer, positioningAreaSize, pixelSnappingFactor); |
| |
| FillRepeat backgroundRepeatX = fillLayer.repeatX(); |
| FillRepeat backgroundRepeatY = fillLayer.repeatY(); |
| LayoutUnit availableWidth = positioningAreaSize.width() - tileSize.width(); |
| LayoutUnit availableHeight = positioningAreaSize.height() - tileSize.height(); |
| |
| LayoutSize spaceSize; |
| LayoutSize phase; |
| LayoutSize noRepeat; |
| LayoutUnit computedXPosition = resolveEdgeRelativeLength(fillLayer.xPosition(), fillLayer.backgroundXOrigin(), availableWidth, positioningAreaSize, tileSize); |
| if (backgroundRepeatX == FillRepeat::Round && positioningAreaSize.width() > 0 && tileSize.width() > 0) { |
| int numTiles = std::max(1, roundToInt(positioningAreaSize.width() / tileSize.width())); |
| if (fillLayer.size().size.height.isAuto() && backgroundRepeatY != FillRepeat::Round) |
| tileSize.setHeight(tileSize.height() * positioningAreaSize.width() / (numTiles * tileSize.width())); |
| |
| tileSize.setWidth(positioningAreaSize.width() / numTiles); |
| phase.setWidth(tileSize.width() ? tileSize.width() - fmodf((computedXPosition + left), tileSize.width()) : 0); |
| } |
| |
| LayoutUnit computedYPosition = resolveEdgeRelativeLength(fillLayer.yPosition(), fillLayer.backgroundYOrigin(), availableHeight, positioningAreaSize, tileSize); |
| if (backgroundRepeatY == FillRepeat::Round && positioningAreaSize.height() > 0 && tileSize.height() > 0) { |
| int numTiles = std::max(1, roundToInt(positioningAreaSize.height() / tileSize.height())); |
| if (fillLayer.size().size.width.isAuto() && backgroundRepeatX != FillRepeat::Round) |
| tileSize.setWidth(tileSize.width() * positioningAreaSize.height() / (numTiles * tileSize.height())); |
| |
| tileSize.setHeight(positioningAreaSize.height() / numTiles); |
| phase.setHeight(tileSize.height() ? tileSize.height() - fmodf((computedYPosition + top), tileSize.height()) : 0); |
| } |
| |
| if (backgroundRepeatX == FillRepeat::Repeat) { |
| phase.setWidth(tileSize.width() ? tileSize.width() - fmodf(computedXPosition + left, tileSize.width()) : 0); |
| spaceSize.setWidth(0); |
| } else if (backgroundRepeatX == FillRepeat::Space && tileSize.width() > 0) { |
| LayoutUnit space = getSpace(positioningAreaSize.width(), tileSize.width()); |
| if (space >= 0) { |
| LayoutUnit actualWidth = tileSize.width() + space; |
| computedXPosition = minimumValueForLength(Length(), availableWidth); |
| spaceSize.setWidth(space); |
| spaceSize.setHeight(0); |
| phase.setWidth(actualWidth ? actualWidth - fmodf((computedXPosition + left), actualWidth) : 0); |
| } else |
| backgroundRepeatX = FillRepeat::NoRepeat; |
| } |
| |
| if (backgroundRepeatX == FillRepeat::NoRepeat) { |
| LayoutUnit xOffset = left + computedXPosition; |
| if (xOffset > 0) |
| destinationRect.move(xOffset, 0_lu); |
| xOffset = std::min<LayoutUnit>(xOffset, 0); |
| phase.setWidth(-xOffset); |
| destinationRect.setWidth(tileSize.width() + xOffset); |
| spaceSize.setWidth(0); |
| } |
| |
| if (backgroundRepeatY == FillRepeat::Repeat) { |
| phase.setHeight(tileSize.height() ? tileSize.height() - fmodf(computedYPosition + top, tileSize.height()) : 0); |
| spaceSize.setHeight(0); |
| } else if (backgroundRepeatY == FillRepeat::Space && tileSize.height() > 0) { |
| LayoutUnit space = getSpace(positioningAreaSize.height(), tileSize.height()); |
| |
| if (space >= 0) { |
| LayoutUnit actualHeight = tileSize.height() + space; |
| computedYPosition = minimumValueForLength(Length(), availableHeight); |
| spaceSize.setHeight(space); |
| phase.setHeight(actualHeight ? actualHeight - fmodf((computedYPosition + top), actualHeight) : 0); |
| } else |
| backgroundRepeatY = FillRepeat::NoRepeat; |
| } |
| if (backgroundRepeatY == FillRepeat::NoRepeat) { |
| LayoutUnit yOffset = top + computedYPosition; |
| if (yOffset > 0) |
| destinationRect.move(0_lu, yOffset); |
| yOffset = std::min<LayoutUnit>(yOffset, 0); |
| phase.setHeight(-yOffset); |
| destinationRect.setHeight(tileSize.height() + yOffset); |
| spaceSize.setHeight(0); |
| } |
| |
| if (fillLayer.attachment() == FillAttachment::FixedBackground) { |
| LayoutPoint attachmentPoint = borderBoxRect.location(); |
| phase.expand(std::max<LayoutUnit>(attachmentPoint.x() - destinationRect.x(), 0), std::max<LayoutUnit>(attachmentPoint.y() - destinationRect.y(), 0)); |
| } |
| |
| destinationRect.intersect(borderBoxRect); |
| return pixelSnappedFillLayerImageGeometry(destinationRect, tileSize, phase, spaceSize, fillLayer.attachment(), pixelSnappingFactor); |
| } |
| |
| Vector<FillLayerImageGeometry, 1> calculateFillLayerImageGeometry(const RenderStyle& renderStyle, const Layout::BoxGeometry& boxGeometry, LayoutSize offsetFromRoot, float pixelSnappingFactor) |
| { |
| // FIXME: Need to map logical to physical rects. |
| auto borderBoxRect = LayoutRect { Layout::BoxGeometry::borderBoxRect(boxGeometry) }; |
| borderBoxRect.move(offsetFromRoot); |
| |
| Vector<FillLayerImageGeometry, 1> backgroundGeometry; |
| |
| for (auto fillLayer = &renderStyle.backgroundLayers(); fillLayer; fillLayer = fillLayer->next()) |
| backgroundGeometry.append(geometryForLayer(*fillLayer, borderBoxRect, boxGeometry, pixelSnappingFactor)); |
| |
| return backgroundGeometry; |
| } |
| |
| } // namespace Display |
| } // namespace WebCore |
| |
| #endif // ENABLE(LAYOUT_FORMATTING_CONTEXT) |
