| /* |
| * Copyright 2017 Google Inc. |
| * |
| * Use of this source code is governed by a BSD-style license that can be |
| * found in the LICENSE file. |
| */ |
| |
| #include "SkSpotShadowMaskFilter.h" |
| #include "SkReadBuffer.h" |
| #include "SkStringUtils.h" |
| #include "SkWriteBuffer.h" |
| |
| #if SK_SUPPORT_GPU |
| #include "GrContext.h" |
| #include "GrRenderTargetContext.h" |
| #include "GrFragmentProcessor.h" |
| #include "GrInvariantOutput.h" |
| #include "GrStyle.h" |
| #include "GrTexture.h" |
| #include "GrTextureProxy.h" |
| #include "glsl/GrGLSLFragmentProcessor.h" |
| #include "glsl/GrGLSLFragmentShaderBuilder.h" |
| #include "glsl/GrGLSLProgramDataManager.h" |
| #include "glsl/GrGLSLUniformHandler.h" |
| #include "SkStrokeRec.h" |
| #endif |
| |
| class SkSpotShadowMaskFilterImpl : public SkMaskFilter { |
| public: |
| SkSpotShadowMaskFilterImpl(SkScalar occluderHeight, const SkPoint3& lightPos, |
| SkScalar lightRadius, SkScalar spotAlpha, uint32_t flags); |
| |
| // overrides from SkMaskFilter |
| SkMask::Format getFormat() const override; |
| bool filterMask(SkMask* dst, const SkMask& src, const SkMatrix&, |
| SkIPoint* margin) const override; |
| |
| #if SK_SUPPORT_GPU |
| bool canFilterMaskGPU(const SkRRect& devRRect, |
| const SkIRect& clipBounds, |
| const SkMatrix& ctm, |
| SkRect* maskRect) const override; |
| bool directFilterMaskGPU(GrTextureProvider* texProvider, |
| GrRenderTargetContext* drawContext, |
| GrPaint&&, |
| const GrClip&, |
| const SkMatrix& viewMatrix, |
| const SkStrokeRec& strokeRec, |
| const SkPath& path) const override; |
| bool directFilterRRectMaskGPU(GrContext*, |
| GrRenderTargetContext* drawContext, |
| GrPaint&&, |
| const GrClip&, |
| const SkMatrix& viewMatrix, |
| const SkStrokeRec& strokeRec, |
| const SkRRect& rrect, |
| const SkRRect& devRRect) const override; |
| sk_sp<GrTextureProxy> filterMaskGPU(GrContext*, |
| sk_sp<GrTextureProxy> srcProxy, |
| const SkMatrix& ctm, |
| const SkIRect& maskRect) const override; |
| #endif |
| |
| void computeFastBounds(const SkRect&, SkRect*) const override; |
| |
| SK_TO_STRING_OVERRIDE() |
| SK_DECLARE_PUBLIC_FLATTENABLE_DESERIALIZATION_PROCS(SkSpotShadowMaskFilterImpl) |
| |
| private: |
| SkScalar fOccluderHeight; |
| SkPoint3 fLightPos; |
| SkScalar fLightRadius; |
| SkScalar fSpotAlpha; |
| uint32_t fFlags; |
| |
| SkSpotShadowMaskFilterImpl(SkReadBuffer&); |
| void flatten(SkWriteBuffer&) const override; |
| |
| friend class SkSpotShadowMaskFilter; |
| |
| typedef SkMaskFilter INHERITED; |
| }; |
| |
| sk_sp<SkMaskFilter> SkSpotShadowMaskFilter::Make(SkScalar occluderHeight, const SkPoint3& lightPos, |
| SkScalar lightRadius, SkScalar spotAlpha, |
| uint32_t flags) { |
| // add some param checks here for early exit |
| |
| return sk_sp<SkMaskFilter>(new SkSpotShadowMaskFilterImpl(occluderHeight, lightPos, |
| lightRadius, spotAlpha, flags)); |
| } |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| SkSpotShadowMaskFilterImpl::SkSpotShadowMaskFilterImpl(SkScalar occluderHeight, |
| const SkPoint3& lightPos, |
| SkScalar lightRadius, |
| SkScalar spotAlpha, |
| uint32_t flags) |
| : fOccluderHeight(occluderHeight) |
| , fLightPos(lightPos) |
| , fLightRadius(lightRadius) |
| , fSpotAlpha(spotAlpha) |
| , fFlags(flags) { |
| SkASSERT(fOccluderHeight > 0); |
| SkASSERT(fLightPos.z() > 0 && fLightPos.z() > fOccluderHeight); |
| SkASSERT(fLightRadius > 0); |
| SkASSERT(fSpotAlpha >= 0); |
| } |
| |
| SkMask::Format SkSpotShadowMaskFilterImpl::getFormat() const { |
| return SkMask::kA8_Format; |
| } |
| |
| bool SkSpotShadowMaskFilterImpl::filterMask(SkMask* dst, const SkMask& src, |
| const SkMatrix& matrix, |
| SkIPoint* margin) const { |
| // TODO something |
| return false; |
| } |
| |
| void SkSpotShadowMaskFilterImpl::computeFastBounds(const SkRect& src, SkRect* dst) const { |
| // TODO compute based on ambient + spot data |
| dst->set(src.fLeft, src.fTop, src.fRight, src.fBottom); |
| } |
| |
| sk_sp<SkFlattenable> SkSpotShadowMaskFilterImpl::CreateProc(SkReadBuffer& buffer) { |
| const SkScalar occluderHeight = buffer.readScalar(); |
| const SkScalar lightX = buffer.readScalar(); |
| const SkScalar lightY = buffer.readScalar(); |
| const SkScalar lightZ = buffer.readScalar(); |
| const SkPoint3 lightPos = SkPoint3::Make(lightX, lightY, lightZ); |
| const SkScalar lightRadius = buffer.readScalar(); |
| const SkScalar spotAlpha = buffer.readScalar(); |
| const uint32_t flags = buffer.readUInt(); |
| |
| return SkSpotShadowMaskFilter::Make(occluderHeight, lightPos, lightRadius, |
| spotAlpha, flags); |
| } |
| |
| void SkSpotShadowMaskFilterImpl::flatten(SkWriteBuffer& buffer) const { |
| buffer.writeScalar(fOccluderHeight); |
| buffer.writeScalar(fLightPos.fX); |
| buffer.writeScalar(fLightPos.fY); |
| buffer.writeScalar(fLightPos.fZ); |
| buffer.writeScalar(fLightRadius); |
| buffer.writeScalar(fSpotAlpha); |
| buffer.writeUInt(fFlags); |
| } |
| |
| #if SK_SUPPORT_GPU |
| |
| /////////////////////////////////////////////////////////////////////////////////////////////////// |
| |
| bool SkSpotShadowMaskFilterImpl::canFilterMaskGPU(const SkRRect& devRRect, |
| const SkIRect& clipBounds, |
| const SkMatrix& ctm, |
| SkRect* maskRect) const { |
| // TODO |
| *maskRect = devRRect.rect(); |
| return true; |
| } |
| |
| bool SkSpotShadowMaskFilterImpl::directFilterMaskGPU(GrTextureProvider* texProvider, |
| GrRenderTargetContext* drawContext, |
| GrPaint&& paint, |
| const GrClip& clip, |
| const SkMatrix& viewMatrix, |
| const SkStrokeRec& strokeRec, |
| const SkPath& path) const { |
| SkASSERT(drawContext); |
| // TODO: this will not handle local coordinates properly |
| |
| // if circle |
| // TODO: switch to SkScalarNearlyEqual when either oval renderer is updated or we |
| // have our own GeometryProc. |
| if (path.isOval(nullptr) && path.getBounds().width() == path.getBounds().height()) { |
| SkRRect rrect = SkRRect::MakeOval(path.getBounds()); |
| return this->directFilterRRectMaskGPU(nullptr, drawContext, std::move(paint), clip, |
| SkMatrix::I(), strokeRec, rrect, rrect); |
| } else if (path.isRect(nullptr)) { |
| SkRRect rrect = SkRRect::MakeRect(path.getBounds()); |
| return this->directFilterRRectMaskGPU(nullptr, drawContext, std::move(paint), clip, |
| SkMatrix::I(), strokeRec, rrect, rrect); |
| } |
| |
| // TODO |
| return false; |
| } |
| |
| bool SkSpotShadowMaskFilterImpl::directFilterRRectMaskGPU(GrContext*, |
| GrRenderTargetContext* rtContext, |
| GrPaint&& paint, |
| const GrClip& clip, |
| const SkMatrix& viewMatrix, |
| const SkStrokeRec& strokeRec, |
| const SkRRect& rrect, |
| const SkRRect& devRRect) const { |
| // It's likely the caller has already done these checks, but we have to be sure. |
| // TODO: support analytic blurring of general rrect |
| |
| // Fast path only supports filled rrects for now. |
| // TODO: fill and stroke as well. |
| if (SkStrokeRec::kFill_Style != strokeRec.getStyle()) { |
| return false; |
| } |
| // Fast path only supports simple rrects with circular corners. |
| SkASSERT(devRRect.allCornersCircular()); |
| if (!rrect.isRect() && !rrect.isOval() && !rrect.isSimple()) { |
| return false; |
| } |
| // Fast path only supports uniform scale. |
| SkScalar scaleFactors[2]; |
| if (!viewMatrix.getMinMaxScales(scaleFactors)) { |
| // matrix is degenerate |
| return false; |
| } |
| if (scaleFactors[0] != scaleFactors[1]) { |
| return false; |
| } |
| SkScalar scaleFactor = scaleFactors[0]; |
| |
| // For all of these, we need to ensure we have a rrect with radius >= 0.5f in device space |
| const SkScalar minRadius = 0.5f / scaleFactor; |
| bool isRect = rrect.getSimpleRadii().fX <= minRadius; |
| |
| // TODO: take flags into account when generating shadow data |
| |
| if (fSpotAlpha > 0.0f) { |
| float zRatio = SkTPin(fOccluderHeight / (fLightPos.fZ - fOccluderHeight), 0.0f, 0.95f); |
| |
| SkScalar srcSpaceSpotRadius = 2.0f * fLightRadius * zRatio; |
| |
| SkRRect spotRRect; |
| if (isRect) { |
| spotRRect = SkRRect::MakeRectXY(rrect.rect(), minRadius, minRadius); |
| } else { |
| spotRRect = rrect; |
| } |
| |
| SkRRect spotShadowRRect; |
| // Compute the scale and translation for the spot shadow. |
| const SkScalar scale = fLightPos.fZ / (fLightPos.fZ - fOccluderHeight); |
| spotRRect.transform(SkMatrix::MakeScale(scale, scale), &spotShadowRRect); |
| |
| SkPoint center = SkPoint::Make(spotShadowRRect.rect().centerX(), |
| spotShadowRRect.rect().centerY()); |
| SkMatrix ctmInverse; |
| if (!viewMatrix.invert(&ctmInverse)) { |
| SkDebugf("Matrix is degenerate. Will not render spot shadow!\n"); |
| //**** TODO: this is not good |
| return true; |
| } |
| SkPoint lightPos2D = SkPoint::Make(fLightPos.fX, fLightPos.fY); |
| ctmInverse.mapPoints(&lightPos2D, 1); |
| const SkPoint spotOffset = SkPoint::Make(zRatio*(center.fX - lightPos2D.fX), |
| zRatio*(center.fY - lightPos2D.fY)); |
| |
| // We want to extend the stroked area in so that it meets up with the caster |
| // geometry. The stroked geometry will, by definition already be inset half the |
| // stroke width but we also have to account for the scaling. |
| SkScalar scaleOffset = (scale - 1.0f) * SkTMax(SkTMax(SkTAbs(rrect.rect().fLeft), |
| SkTAbs(rrect.rect().fRight)), |
| SkTMax(SkTAbs(rrect.rect().fTop), |
| SkTAbs(rrect.rect().fBottom))); |
| SkScalar insetAmount = spotOffset.length() - (0.5f * srcSpaceSpotRadius) + scaleOffset; |
| |
| // Compute area |
| SkScalar strokeWidth = srcSpaceSpotRadius + insetAmount; |
| SkScalar strokedArea = 2.0f*strokeWidth * |
| (spotShadowRRect.width() + spotShadowRRect.height()); |
| SkScalar filledArea = (spotShadowRRect.height() + srcSpaceSpotRadius) * |
| (spotShadowRRect.width() + srcSpaceSpotRadius); |
| |
| GrColor4f color = paint.getColor4f(); |
| color.fRGBA[3] *= fSpotAlpha; |
| paint.setColor4f(color); |
| |
| SkStrokeRec spotStrokeRec(SkStrokeRec::kFill_InitStyle); |
| // If the area of the stroked geometry is larger than the fill geometry, |
| // or if the caster is transparent, just fill it. |
| if (strokedArea > filledArea || |
| fFlags & SkShadowFlags::kTransparentOccluder_ShadowFlag) { |
| spotStrokeRec.setStrokeStyle(srcSpaceSpotRadius, true); |
| } else { |
| // Since we can't have unequal strokes, inset the shadow rect so the inner |
| // and outer edges of the stroke will land where we want. |
| SkRect insetRect = spotShadowRRect.rect().makeInset(insetAmount / 2.0f, |
| insetAmount / 2.0f); |
| SkScalar insetRad = SkTMax(spotShadowRRect.getSimpleRadii().fX - insetAmount / 2.0f, |
| minRadius); |
| spotShadowRRect = SkRRect::MakeRectXY(insetRect, insetRad, insetRad); |
| spotStrokeRec.setStrokeStyle(strokeWidth, false); |
| } |
| |
| // handle scale of radius and pad due to CTM |
| const SkScalar devSpaceSpotRadius = srcSpaceSpotRadius * scaleFactor; |
| |
| spotShadowRRect.offset(spotOffset.fX, spotOffset.fY); |
| |
| rtContext->drawShadowRRect(clip, std::move(paint), viewMatrix, spotShadowRRect, |
| devSpaceSpotRadius, GrStyle(spotStrokeRec, nullptr)); |
| } |
| |
| return true; |
| } |
| |
| sk_sp<GrTextureProxy> SkSpotShadowMaskFilterImpl::filterMaskGPU(GrContext*, |
| sk_sp<GrTextureProxy> srcProxy, |
| const SkMatrix& ctm, |
| const SkIRect& maskRect) const { |
| // This filter is generative and doesn't operate on pre-existing masks |
| return nullptr; |
| } |
| |
| #endif |
| |
| #ifndef SK_IGNORE_TO_STRING |
| void SkSpotShadowMaskFilterImpl::toString(SkString* str) const { |
| str->append("SkSpotShadowMaskFilterImpl: ("); |
| |
| str->append("occluderHeight: "); |
| str->appendScalar(fOccluderHeight); |
| str->append(" "); |
| |
| str->append("lightPos: ("); |
| str->appendScalar(fLightPos.fX); |
| str->append(", "); |
| str->appendScalar(fLightPos.fY); |
| str->append(", "); |
| str->appendScalar(fLightPos.fZ); |
| str->append(") "); |
| |
| str->append("lightRadius: "); |
| str->appendScalar(fLightRadius); |
| str->append(" "); |
| |
| str->append("spotAlpha: "); |
| str->appendScalar(fSpotAlpha); |
| str->append(" "); |
| |
| str->append("flags: ("); |
| if (fFlags) { |
| bool needSeparator = false; |
| SkAddFlagToString(str, |
| SkToBool(fFlags & SkShadowFlags::kTransparentOccluder_ShadowFlag), |
| "TransparentOccluder", &needSeparator); |
| SkAddFlagToString(str, |
| SkToBool(fFlags & SkShadowFlags::kGaussianEdge_ShadowFlag), |
| "GaussianEdge", &needSeparator); |
| SkAddFlagToString(str, |
| SkToBool(fFlags & SkShadowFlags::kLargerUmbra_ShadowFlag), |
| "LargerUmbra", &needSeparator); |
| } else { |
| str->append("None"); |
| } |
| str->append("))"); |
| } |
| #endif |
| |
| SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_START(SkSpotShadowMaskFilter) |
| SK_DEFINE_FLATTENABLE_REGISTRAR_ENTRY(SkSpotShadowMaskFilterImpl) |
| SK_DEFINE_FLATTENABLE_REGISTRAR_GROUP_END |
