Factor out a BaseContext from JsContext.

experimental/SkV8Example/BaseContext.cpp

+/*
+ * Copyright 2014 Google Inc.
+ *
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ *
+ */
+#include <v8.h>
+
+using namespace v8;
+
+#include "Global.h"
+#include "BaseContext.h"
+#include "Path2D.h"
+#include "SkCanvas.h"
+
+
+BaseContext* BaseContext::Unwrap(Handle<Object> obj) {
+    Handle<External> field = Handle<External>::Cast(obj->GetInternalField(0));
+    void* ptr = field->Value();
+    return static_cast<BaseContext*>(ptr);
+}
+
+void BaseContext::FillRect(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    if (args.Length() != 4) {
+        args.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        args.GetIsolate(), "Error: 4 arguments required."));
+        return;
+    }
+    double x = args[0]->NumberValue();
+    double y = args[1]->NumberValue();
+    double w = args[2]->NumberValue();
+    double h = args[3]->NumberValue();
+
+    SkRect rect = {
+        SkDoubleToScalar(x),
+        SkDoubleToScalar(y),
+        SkDoubleToScalar(x) + SkDoubleToScalar(w),
+        SkDoubleToScalar(y) + SkDoubleToScalar(h)
+    };
+    canvas->drawRect(rect, BaseContext->fFillStyle);
+}
+
+void BaseContext::Save(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    canvas->save();
+}
+
+void BaseContext::Restore(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    canvas->restore();
+}
+
+void BaseContext::Rotate(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    if (args.Length() != 1) {
+        args.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        args.GetIsolate(), "Error: 1 arguments required."));
+        return;
+    }
+    double angle = args[0]->NumberValue();
+    canvas->rotate(SkRadiansToDegrees(angle));
+}
+
+void BaseContext::Translate(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    if (args.Length() != 2) {
+        args.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        args.GetIsolate(), "Error: 2 arguments required."));
+        return;
+    }
+    double dx = args[0]->NumberValue();
+    double dy = args[1]->NumberValue();
+    canvas->translate(SkDoubleToScalar(dx), SkDoubleToScalar(dy));
+}
+
+void BaseContext::ResetTransform(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    canvas->resetMatrix();
+}
+
+void BaseContext::Stroke(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    if (args.Length() != 1) {
+        args.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        args.GetIsolate(), "Error: 1 arguments required."));
+        return;
+    }
+
+    Handle<External> field = Handle<External>::Cast(
+            args[0]->ToObject()->GetInternalField(0));
+    void* ptr = field->Value();
+    Path2D* path = static_cast<Path2D*>(ptr);
+
+    canvas->drawPath(path->getSkPath(), BaseContext->fStrokeStyle);
+}
+
+void BaseContext::Fill(const v8::FunctionCallbackInfo<Value>& args) {
+    BaseContext* BaseContext = Unwrap(args.This());
+    SkCanvas* canvas = BaseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+
+    if (args.Length() != 1) {
+        args.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        args.GetIsolate(), "Error: 1 arguments required."));
+        return;
+    }
+
+    Handle<External> field = Handle<External>::Cast(
+            args[0]->ToObject()->GetInternalField(0));
+    void* ptr = field->Value();
+    Path2D* path = static_cast<Path2D*>(ptr);
+
+    canvas->drawPath(path->getSkPath(), BaseContext->fFillStyle);
+}
+
+void BaseContext::GetStyle(Local<String> name,
+                         const PropertyCallbackInfo<Value>& info,
+                         const SkPaint& style) {
+    char buf[8];
+    SkColor color = style.getColor();
+    sprintf(buf, "#%02X%02X%02X", SkColorGetR(color), SkColorGetG(color),
+            SkColorGetB(color));
+
+    info.GetReturnValue().Set(String::NewFromUtf8(info.GetIsolate(), buf));
+}
+
+void BaseContext::SetStyle(Local<String> name, Local<Value> value,
+                         const PropertyCallbackInfo<void>& info,
+                         SkPaint& style) {
+    Local<String> s = value->ToString();
+    if (s->Length() != 7 && s->Length() != 9) {
+        info.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        info.GetIsolate(),
+                        "Invalid fill style format length."));
+        return;
+    }
+    char buf[10];
+    s->WriteUtf8(buf, sizeof(buf));
+
+    if (buf[0] != '#') {
+        info.GetIsolate()->ThrowException(
+                v8::String::NewFromUtf8(
+                        info.GetIsolate(), "Invalid fill style format."));
+        return;
+    }
+
+    // Colors can be RRGGBBAA, but SkColor uses ARGB.
+    long color = strtol(buf+1, NULL, 16);
+    uint32_t alpha = SK_AlphaOPAQUE;
+    if (s->Length() == 9) {
+        alpha = color & 0xFF;
+        color >>= 8;
+    }
+    style.setColor(SkColorSetA(SkColor(color), alpha));
+}
+
+void BaseContext::GetFillStyle(Local<String> name,
+                             const PropertyCallbackInfo<Value>& info) {
+    BaseContext* baseContext = Unwrap(info.This());
+    GetStyle(name, info, baseContext->fFillStyle);
+}
+
+void BaseContext::GetStrokeStyle(Local<String> name,
+                               const PropertyCallbackInfo<Value>& info) {
+    BaseContext* baseContext = Unwrap(info.This());
+    GetStyle(name, info, baseContext->fStrokeStyle);
+}
+
+void BaseContext::SetFillStyle(Local<String> name, Local<Value> value,
+                            const PropertyCallbackInfo<void>& info) {
+    BaseContext* baseContext = Unwrap(info.This());
+    SetStyle(name, value, info, baseContext->fFillStyle);
+}
+
+void BaseContext::SetStrokeStyle(Local<String> name, Local<Value> value,
+                               const PropertyCallbackInfo<void>& info) {
+    BaseContext* baseContext = Unwrap(info.This());
+    SetStyle(name, value, info, baseContext->fStrokeStyle);
+}
+
+
+void BaseContext::GetWidth(Local<String> name,
+                         const PropertyCallbackInfo<Value>& info) {
+    BaseContext* baseContext = Unwrap(info.This());
+    SkCanvas* canvas = baseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+    SkISize size = canvas->getDeviceSize();
+
+    info.GetReturnValue().Set(
+            Int32::New(baseContext->fGlobal->getIsolate(), size.fWidth));
+}
+
+void BaseContext::GetHeight(Local<String> name,
+                         const PropertyCallbackInfo<Value>& info) {
+    BaseContext* baseContext = Unwrap(info.This());
+    SkCanvas* canvas = baseContext->getCanvas();
+    if (NULL == canvas) {
+        return;
+    }
+    SkISize size = canvas->getDeviceSize();
+
+    info.GetReturnValue().Set(
+            Int32::New(baseContext->fGlobal->getIsolate(), size.fHeight));
+}
+
+#define ADD_METHOD(name, fn) \
+    tmpl->Set(String::NewFromUtf8( \
+         fGlobal->getIsolate(), name, \
+         String::kInternalizedString), \
+             FunctionTemplate::New(fGlobal->getIsolate(), fn))
+
+void BaseContext::addAttributesAndMethods(Handle<ObjectTemplate> tmpl) {
+    HandleScope scope(fGlobal->getIsolate());
+
+    // Add accessors for each of the fields of the context object.
+    tmpl->SetAccessor(String::NewFromUtf8(
+        fGlobal->getIsolate(), "fillStyle", String::kInternalizedString),
+            GetFillStyle, SetFillStyle);
+    tmpl->SetAccessor(String::NewFromUtf8(
+        fGlobal->getIsolate(), "strokeStyle", String::kInternalizedString),
+            GetStrokeStyle, SetStrokeStyle);
+    tmpl->SetAccessor(String::NewFromUtf8(
+        fGlobal->getIsolate(), "width", String::kInternalizedString),
+            GetWidth);
+    tmpl->SetAccessor(String::NewFromUtf8(
+        fGlobal->getIsolate(), "height", String::kInternalizedString),
+            GetHeight);
+
+    // Add methods.
+    ADD_METHOD("fillRect", FillRect);
+    ADD_METHOD("stroke", Stroke);
+    ADD_METHOD("fill", Fill);
+    ADD_METHOD("rotate", Rotate);
+    ADD_METHOD("save", Save);
+    ADD_METHOD("restore", Restore);
+    ADD_METHOD("translate", Translate);
+    ADD_METHOD("resetTransform", ResetTransform);
+}