Revert of Improve usage of window rectangles

gm/windowrectangles.cpp

-/*
- * Copyright 2016 Google Inc.
- *
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "gm.h"
-#include "SkClipStack.h"
-#include "SkRRect.h"
-
-#if SK_SUPPORT_GPU
-#  include "GrAppliedClip.h"
-#  include "GrDrawContext.h"
-#  include "GrDrawContextPriv.h"
-#  include "GrFixedClip.h"
-#  include "GrReducedClip.h"
-#  include "GrRenderTargetPriv.h"
-#  include "GrResourceProvider.h"
-#  include "effects/GrTextureDomain.h"
-#endif
-
-constexpr static SkIRect kDeviceRect = {0, 0, 600, 600};
-constexpr static SkIRect kLayerRect = {25, 25, 575, 575};
-constexpr static SkIRect kCoverRect = {50, 50, 550, 550};
-constexpr static int kNumWindows = 8;
-
-namespace skiagm {
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-class WindowRectanglesBaseGM : public GM {
-protected:
-    virtual void onCoverClipStack(const SkClipStack&, SkCanvas*) = 0;
-
-private:
-    SkISize onISize() override { return SkISize::Make(kDeviceRect.width(), kDeviceRect.height()); }
-    void onDraw(SkCanvas*) final;
-};
-
-void WindowRectanglesBaseGM::onDraw(SkCanvas* canvas) {
-    sk_tool_utils::draw_checkerboard(canvas, 0xffffffff, 0xffc6c3c6, 25);
-    canvas->saveLayer(SkRect::Make(kLayerRect), nullptr);
-
-    SkClipStack stack;
-    stack.clipDevRect(SkRect::MakeXYWH(370.75, 80.25, 149, 100), SkRegion::kDifference_Op, false);
-    stack.clipDevRect(SkRect::MakeXYWH(80.25, 420.75, 150, 100), SkRegion::kDifference_Op, true);
-    stack.clipDevRRect(SkRRect::MakeRectXY(SkRect::MakeXYWH(200, 200, 200, 200), 60, 45),
-                       SkRegion::kDifference_Op, true);
-
-    SkRRect nine;
-    nine.setNinePatch(SkRect::MakeXYWH(550 - 30.25 - 100, 370.75, 100, 150), 12, 35, 23, 20);
-    stack.clipDevRRect(nine, SkRegion::kDifference_Op, true);
-
-    SkRRect complx;
-    SkVector complxRadii[4] = {{6, 4}, {8, 12}, {16, 24}, {48, 32}};
-    complx.setRectRadii(SkRect::MakeXYWH(80.25, 80.75, 100, 149), complxRadii);
-    stack.clipDevRRect(complx, SkRegion::kDifference_Op, false);
-
-    this->onCoverClipStack(stack, canvas);
-
-    canvas->restore();
-}
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-/**
- * Draws a clip that will exercise window rectangles if they are supported.
- */
-class WindowRectanglesGM : public WindowRectanglesBaseGM {
-private:
-    SkString onShortName() final { return SkString("windowrectangles"); }
-    void onCoverClipStack(const SkClipStack&, SkCanvas*) final;
-};
-
-/**
- * This is a simple helper class for resetting a canvas's clip to our test’s SkClipStack.
- */
-class ReplayClipStackVisitor final : public SkCanvasClipVisitor {
-public:
-    typedef SkRegion::Op Op;
-    ReplayClipStackVisitor(SkCanvas* canvas) : fCanvas(canvas) {}
-    void clipRect(const SkRect& r, Op op, bool aa) override { fCanvas->clipRect(r, op, aa); }
-    void clipRRect(const SkRRect& rr, Op op, bool aa) override { fCanvas->clipRRect(rr, op, aa); }
-    void clipPath(const SkPath&, Op, bool) override { SkFAIL("Not implemented"); }
-private:
-    SkCanvas* const fCanvas;
-};
-
-void WindowRectanglesGM::onCoverClipStack(const SkClipStack& stack, SkCanvas* canvas) {
-    SkPaint paint;
-    paint.setColor(0xff00aa80);
-
-    // Set up the canvas's clip to match our SkClipStack.
-    ReplayClipStackVisitor visitor(canvas);
-    SkClipStack::Iter iter(stack, SkClipStack::Iter::kBottom_IterStart);
-    for (const SkClipStack::Element* element = iter.next(); element; element = iter.next()) {
-        element->replay(&visitor);
-    }
-
-    canvas->drawRect(SkRect::Make(kCoverRect), paint);
-}
-
-DEF_GM( return new WindowRectanglesGM(); )
-
-////////////////////////////////////////////////////////////////////////////////////////////////////
-
-#if SK_SUPPORT_GPU
-
-/**
- * Visualizes the mask (alpha or stencil) for a clip with several window rectangles. The purpose of
- * this test is to verify that window rectangles are being used during clip mask generation, and to
- * visualize where the window rectangles are placed.
- *
- * We use window rectangles when generating the clip mask because there is no need to invest time
- * defining those regions where window rectangles will be in effect during the actual draw anyway.
- *
- * This test works by filling the entire clip mask with a small checkerboard pattern before drawing
- * it, and then covering the mask with a solid color once it has been generated. The regions inside
- * window rectangles or outside the scissor should still have the initial checkerboard intact.
- */
-class WindowRectanglesMaskGM : public WindowRectanglesBaseGM {
-private:
-    constexpr static int kMaskCheckerSize = 5;
-    SkString onShortName() final { return SkString("windowrectangles_mask"); }
-    void onCoverClipStack(const SkClipStack&, SkCanvas*) final;
-    void visualizeAlphaMask(GrContext*, GrDrawContext*, const GrReducedClip&, const GrPaint&);
-    void visualizeStencilMask(GrContext*, GrDrawContext*, const GrReducedClip&, const GrPaint&);
-    void stencilCheckerboard(GrDrawContext*, bool flip);
-    void fail(SkCanvas*);
-};
-
-/**
- * Base class for GrClips that visualize a clip mask.
- */
-class MaskOnlyClipBase : public GrClip {
-private:
-    bool quickContains(const SkRect&) const final { return false; }
-    bool isRRect(const SkRect& rtBounds, SkRRect* rr, bool* aa) const final { return false; }
-    void getConservativeBounds(int width, int height, SkIRect* rect, bool* iior) const final {
-        rect->set(0, 0, width, height);
-        if (iior) {
-            *iior = false;
-        }
-    }
-};
-
-/**
- * This class clips a cover by an alpha mask. We use it to visualize the alpha clip mask.
- */
-class AlphaOnlyClip final : public MaskOnlyClipBase {
-public:
-    AlphaOnlyClip(GrTexture* mask, int x, int y) {
-        int w = mask->width(), h = mask->height();
-        SkMatrix mat = SkMatrix::MakeScale(1.f / SkIntToScalar(w), 1.f / SkIntToScalar(h));
-        mat.preTranslate(SkIntToScalar(-x), SkIntToScalar(-y));
-        fFP = GrTextureDomainEffect::Make(
-                  mask, nullptr, mat,
-                  GrTextureDomain::MakeTexelDomain(mask, SkIRect::MakeWH(w, h)),
-                  GrTextureDomain::kDecal_Mode, GrTextureParams::kNone_FilterMode,
-                  kDevice_GrCoordSet);
-
-    }
-private:
-    bool apply(GrContext*, GrDrawContext*, bool, bool, GrAppliedClip* out) const override {
-        out->addCoverageFP(fFP);
-        return true;
-    }
-    sk_sp<GrFragmentProcessor> fFP;
-};
-
-/**
- * This class clips a cover by the stencil clip bit. We use it to visualize the stencil mask.
- */
-class StencilOnlyClip final : public MaskOnlyClipBase {
-private:
-    bool apply(GrContext*, GrDrawContext*, bool, bool, GrAppliedClip* out) const override {
-        out->addStencilClip();
-        return true;
-    }
-};
-
-void WindowRectanglesMaskGM::onCoverClipStack(const SkClipStack& stack, SkCanvas* canvas) {
-    GrContext* ctx = canvas->getGrContext();
-    GrDrawContext* dc = canvas->internal_private_accessTopLayerDrawContext();
-
-    if (!ctx || !dc ||
-        dc->accessRenderTarget()->renderTargetPriv().maxWindowRectangles() < kNumWindows) {
-        this->fail(canvas);
-        return;
-    }
-
-    const GrReducedClip reducedClip(stack, SkRect::Make(kCoverRect), kNumWindows);
-
-    GrPaint paint;
-    paint.setAntiAlias(true);
-    if (!dc->isStencilBufferMultisampled()) {
-        paint.setColor4f(GrColor4f(0, 0.25f, 1, 1));
-        this->visualizeAlphaMask(ctx, dc, reducedClip, paint);
-    } else {
-        paint.setColor4f(GrColor4f(1, 0.25f, 0.25f, 1));
-        this->visualizeStencilMask(ctx, dc, reducedClip, paint);
-    }
-}
-
-void WindowRectanglesMaskGM::visualizeAlphaMask(GrContext* ctx, GrDrawContext* dc,
-                                                const GrReducedClip& reducedClip,
-                                                const GrPaint& paint) {
-    GrPixelConfig config = kRGBA_8888_GrPixelConfig;
-    if (ctx->caps()->isConfigRenderable(kAlpha_8_GrPixelConfig, false)) {
-        config = kAlpha_8_GrPixelConfig;
-    }
-
-    sk_sp<GrDrawContext> maskDC(ctx->makeDrawContext(SkBackingFit::kExact, kLayerRect.width(),
-                                                     kLayerRect.height(), config, nullptr));
-    if (!maskDC ||
-        !ctx->resourceProvider()->attachStencilAttachment(maskDC->accessRenderTarget())) {
-        return;
-    }
-
-    // Draw a checker pattern into the alpha mask so we can visualize the regions left untouched by
-    // the clip mask generation.
-    this->stencilCheckerboard(maskDC.get(), true);
-    maskDC->clear(nullptr, GrColorPackA4(0xff), true);
-    maskDC->drawContextPriv().drawAndStencilRect(StencilOnlyClip(), &GrUserStencilSettings::kUnused,
-                                                 SkRegion::kDifference_Op, false, false,
-                                                 SkMatrix::I(),
-                                                 SkRect::MakeIWH(maskDC->width(), maskDC->height()));
-    reducedClip.drawAlphaClipMask(maskDC.get());
-    sk_sp<GrTexture> mask(maskDC->asTexture());
-
-    int x = kCoverRect.x() - kLayerRect.x(),
-        y = kCoverRect.y() - kLayerRect.y();
-
-    // Now visualize the alpha mask by drawing a rect over the area where it is defined. The regions
-    // inside window rectangles or outside the scissor should still have the initial checkerboard
-    // intact. (This verifies we didn't spend any time modifying those pixels in the mask.)
-    AlphaOnlyClip clip(mask.get(), x, y);
-    dc->drawRect(clip, paint, SkMatrix::I(),
-                 SkRect::Make(SkIRect::MakeXYWH(x, y, mask->width(), mask->height())));
-}
-
-void WindowRectanglesMaskGM::visualizeStencilMask(GrContext* ctx, GrDrawContext* dc,
-                                                  const GrReducedClip& reducedClip,
-                                                  const GrPaint& paint) {
-    if (!ctx->resourceProvider()->attachStencilAttachment(dc->accessRenderTarget())) {
-        return;
-    }
-
-    // Draw a checker pattern into the stencil buffer so we can visualize the regions left untouched
-    // by the clip mask generation.
-    this->stencilCheckerboard(dc, false);
-    reducedClip.drawStencilClipMask(ctx, dc, {kLayerRect.x(), kLayerRect.y()});
-
-    // Now visualize the stencil mask by covering the entire render target. The regions inside
-    // window rectangless or outside the scissor should still have the initial checkerboard intact.
-    // (This verifies we didn't spend any time modifying those pixels in the mask.)
-    dc->drawPaint(StencilOnlyClip(), paint, SkMatrix::I());
-}
-
-void WindowRectanglesMaskGM::stencilCheckerboard(GrDrawContext* dc, bool flip) {
-    constexpr static GrUserStencilSettings kSetClip(
-        GrUserStencilSettings::StaticInit<
-        0,
-        GrUserStencilTest::kAlways,
-        0,
-        GrUserStencilOp::kSetClipBit,
-        GrUserStencilOp::kKeep,
-        0>()
-    );
-
-    dc->drawContextPriv().clearStencilClip(GrFixedClip::Disabled(), false);
-
-    for (int y = 0; y < kLayerRect.height(); y += kMaskCheckerSize) {
-        for (int x = (y & 1) == flip ? 0 : kMaskCheckerSize;
-             x < kLayerRect.width(); x += 2 * kMaskCheckerSize) {
-            SkIRect checker = SkIRect::MakeXYWH(x, y, kMaskCheckerSize, kMaskCheckerSize);
-            dc->drawContextPriv().stencilRect(GrNoClip(), &kSetClip, false, SkMatrix::I(),
-                                              SkRect::Make(checker));
-        }
-    }
-}
-
-void WindowRectanglesMaskGM::fail(SkCanvas* canvas) {
-    SkPaint paint;
-    paint.setAntiAlias(true);
-    paint.setTextAlign(SkPaint::kCenter_Align);
-    paint.setTextSize(20);
-    sk_tool_utils::set_portable_typeface(&paint);
-
-    SkString errorMsg;
-    errorMsg.printf("Requires GPU with %i window rectangles", kNumWindows);
-
-    canvas->clipRect(SkRect::Make(kCoverRect));
-    canvas->clear(SK_ColorWHITE);
-    canvas->drawText(errorMsg.c_str(), errorMsg.size(), SkIntToScalar(kCoverRect.centerX()),
-                     SkIntToScalar(kCoverRect.centerY() - 10), paint);
-}
-
-DEF_GM( return new WindowRectanglesMaskGM(); )
-
-#endif
-
-}