Demo Class Reference

Public Member Functions
bool	init (std::string canvasSelector, int width, int height)
void	setKind (DemoKind kind)
void	draw (int timestamp)
void	drawSolidColor (SkPaint *paint)
void	drawGradient (SkPaint *paint)
void	drawRuntimeEffect (SkPaint *paint, int timestamp)

Detailed Description

Definition at line 72 of file bindings.cpp.

Member Function Documentation

draw()

void Demo::draw ( int  timestamp )

inline

Definition at line 123 of file bindings.cpp.

                             {
        GrDawnRenderTargetInfo rtInfo;
        rtInfo.fTextureView = fCanvasSwapChain.GetCurrentTextureView();
        rtInfo.fFormat = wgpu::TextureFormat::BGRA8Unorm;
        rtInfo.fLevelCount = 1;
        GrBackendRenderTarget backendRenderTarget(fWidth, fHeight, 1, 8, rtInfo);
        SkSurfaceProps surfaceProps(0, kRGB_H_SkPixelGeometry);
 
        sk_sp<SkSurface> surface = SkSurfaces::WrapBackendRenderTarget(fContext.get(),
                                                                       backendRenderTarget,
                                                                       kTopLeft_GrSurfaceOrigin,
                                                                       kN32_SkColorType,
                                                                       nullptr,
                                                                       &surfaceProps);
 
        SkPaint paint;
        if (fDemoKind == DemoKind::SOLID_COLOR) {
            drawSolidColor(&paint);
        } else if (fDemoKind == DemoKind::GRADIENT) {
            drawGradient(&paint);
        } else if (fDemoKind == DemoKind::RUNTIME_EFFECT) {
            drawRuntimeEffect(&paint, timestamp);
        }
 
        // Schedule the recorded commands and wait until the GPU has executed them.
        surface->getCanvas()->drawPaint(paint);
        fContext->flushAndSubmit(surface, true);
        fFrameCount++;
    }

drawGradient()

void Demo::drawGradient ( SkPaint *  paint )

inline

Definition at line 158 of file bindings.cpp.

                                      {
        bool flipColor = fFrameCount % 2 == 0;
        SkColor colors1[2] = {SK_ColorMAGENTA, SK_ColorCYAN};
        SkColor colors2[2] = {SK_ColorCYAN, SK_ColorMAGENTA};
 
        float x = (float)fWidth / 2.f;
        float y = (float)fHeight / 2.f;
        paint->setShader(SkGradientShader::MakeRadial(SkPoint::Make(x, y),
                                                      std::min(x, y),
                                                      flipColor ? colors1 : colors2,
                                                      nullptr,
                                                      2,
                                                      SkTileMode::kClamp));
    }

drawRuntimeEffect()

void Demo::drawRuntimeEffect ( SkPaint *  paint, int  timestamp  )

inline

Definition at line 173 of file bindings.cpp.

                                                          {
        DemoUniforms uniforms;
        uniforms.width = fWidth;
        uniforms.height = fHeight;
        uniforms.time = static_cast<float>(timestamp) / 1000.f;
 
        sk_sp<SkData> uniformData = SkData::MakeWithCopy(&uniforms, sizeof(uniforms));
        sk_sp<SkShader> shader = fEffect->makeShader(std::move(uniformData), /*children=*/{});
        paint->setShader(shader);
    }

drawSolidColor()

void Demo::drawSolidColor ( SkPaint *  paint )

inline

Definition at line 153 of file bindings.cpp.

                                        {
        bool flipColor = fFrameCount % 2 == 0;
        paint->setColor(flipColor ? SK_ColorCYAN : SK_ColorMAGENTA);
    }

init()

bool Demo::init ( std::string  canvasSelector, int  width, int  height  )

inline

Definition at line 74 of file bindings.cpp.

                                                               {
        GrContextOptions ctxOpts;
 
        wgpu::Device device = wgpu::Device::Acquire(emscripten_webgpu_get_device());
        sk_sp<GrDirectContext> context = GrDirectContext::MakeDawn(device, ctxOpts);
        if (!context) {
            SkDebugf("Could not create GrDirectContext\n");
            return false;
        }
 
        const char* sksl =
                "uniform float2 iResolution;"
                "uniform float iTime;"
                "vec2 d;"
                "float b(float a) {"
                "  return step(max(d.x, d.y), a);"
                "}"
                "half4 main(float2 C) {"
                "  vec4 O = vec4(0);"
                "  C.y = iResolution.y - C.y;"
                "  for (float i = 0; i < 3; ++i) {"
                "    vec2 U = C.yx / iResolution.yx;"
                "    U.y -= .5;"
                "    U.x = U.x * .4 + U.y * U.y;"
                "    U.y += U.x * sin(-iTime * 9. + i * 2. + U.x * 25.) * .2;"
                "    U.x -= asin(sin(U.y * 34.))/20.;"
                "    d = abs(U);"
                "    O += .3 * vec4(.8 * b(.3) + b(.2), b(.2), b(.1), -1.);"
                "  }"
                "  return O.xyz1;"
                "}";
 
        auto [effect, err] = SkRuntimeEffect::MakeForShader(SkString(sksl));
        if (!effect) {
            SkDebugf("Failed to compile SkSL: %s\n", err.c_str());
            return false;
        }
 
        fWidth = width;
        fHeight = height;
        fCanvasSwapChain = getSwapChainForCanvas(device, canvasSelector, width, height);
        fContext = context;
        fEffect = effect;
 
        return true;
    }

setKind()

void Demo::setKind ( DemoKind  kind )

inline

Definition at line 121 of file bindings.cpp.

{ fDemoKind = kind; }

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The documentation for this class was generated from the following file:

• third_party/skia/experimental/webgpu-bazel/src/bindings.cpp