Factor out a BaseContext from JsContext.

experimental/SkV8Example/JsContext.cpp

 
 /*
  * Copyright 2013 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 "JsContext.h"
 #include "Path2D.h"
 #include "SkCanvas.h"
 
 
 // Extracts a C string from a V8 Utf8Value.
 // TODO(jcgregrio) Currently dup'd in two files, fix.
 static const char* to_cstring(const v8::String::Utf8Value& value) {
     return *value ? *value : "<string conversion failed>";
 }
 
-JsContext* JsContext::Unwrap(Handle<Object> obj) {
-    Handle<External> field = Handle<External>::Cast(obj->GetInternalField(0));
-    void* ptr = field->Value();
-    return static_cast<JsContext*>(ptr);
-}
-
-void JsContext::FillRect(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    if (args.Length() != 4) {
-        args.GetIsolate()->ThrowException(
-                v8::String::NewFromUtf8(
-                        args.GetIsolate(), "Error: 4 arguments required."));
-        return;
-    }
-    // TODO(jcgregorio) Really figure out the conversion from JS numbers to
-    // SkScalars. Maybe test if int first? Not sure of the performance impact.
-    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, jsContext->fFillStyle);
-}
-
-void JsContext::Save(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    canvas->save();
-}
-
-void JsContext::Restore(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    canvas->restore();
-}
-
-void JsContext::Rotate(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    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 JsContext::Translate(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    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 JsContext::ResetTransform(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    canvas->resetMatrix();
-}
-
-void JsContext::Stroke(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    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(), jsContext->fStrokeStyle);
-}
-
-void JsContext::Fill(const v8::FunctionCallbackInfo<Value>& args) {
-    JsContext* jsContext = Unwrap(args.This());
-    SkCanvas* canvas = jsContext->fCanvas;
-
-    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(), jsContext->fFillStyle);
-}
-
-void JsContext::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 JsContext::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 JsContext::GetFillStyle(Local<String> name,
-                             const PropertyCallbackInfo<Value>& info) {
-    JsContext* jsContext = Unwrap(info.This());
-    GetStyle(name, info, jsContext->fFillStyle);
-}
-
-void JsContext::GetStrokeStyle(Local<String> name,
-                               const PropertyCallbackInfo<Value>& info) {
-    JsContext* jsContext = Unwrap(info.This());
-    GetStyle(name, info, jsContext->fStrokeStyle);
-}
-
-void JsContext::SetFillStyle(Local<String> name, Local<Value> value,
-                            const PropertyCallbackInfo<void>& info) {
-    JsContext* jsContext = Unwrap(info.This());
-    SetStyle(name, value, info, jsContext->fFillStyle);
-}
-
-void JsContext::SetStrokeStyle(Local<String> name, Local<Value> value,
-                               const PropertyCallbackInfo<void>& info) {
-    JsContext* jsContext = Unwrap(info.This());
-    SetStyle(name, value, info, jsContext->fStrokeStyle);
-}
-
-
-void JsContext::GetWidth(Local<String> name,
-                         const PropertyCallbackInfo<Value>& info) {
-    JsContext* jsContext = Unwrap(info.This());
-    SkISize size = jsContext->fCanvas->getDeviceSize();
-
-    info.GetReturnValue().Set(
-            Int32::New(jsContext->fGlobal->getIsolate(), size.fWidth));
-}
-
-void JsContext::GetHeight(Local<String> name,
-                         const PropertyCallbackInfo<Value>& info) {
-    JsContext* jsContext = Unwrap(info.This());
-    SkISize size = jsContext->fCanvas->getDeviceSize();
-
-    info.GetReturnValue().Set(
-            Int32::New(jsContext->fGlobal->getIsolate(), size.fHeight));
-}
-
-
 Persistent<ObjectTemplate> JsContext::gContextTemplate;
 
-#define ADD_METHOD(name, fn) \
-    result->Set(String::NewFromUtf8( \
-            fGlobal->getIsolate(), name, \
-            String::kInternalizedString), \
-                FunctionTemplate::New(fGlobal->getIsolate(), fn))
-
-Handle<ObjectTemplate> JsContext::makeContextTemplate() {
-    EscapableHandleScope handleScope(fGlobal->getIsolate());
-
-    Local<ObjectTemplate> result = ObjectTemplate::New();
-
-    // Add a field to store the pointer to a JsContext instance.
-    result->SetInternalFieldCount(1);
-
-    // Add accessors for each of the fields of the context object.
-    result->SetAccessor(String::NewFromUtf8(
-            fGlobal->getIsolate(), "fillStyle", String::kInternalizedString),
-                        GetFillStyle, SetFillStyle);
-    result->SetAccessor(String::NewFromUtf8(
-            fGlobal->getIsolate(), "strokeStyle", String::kInternalizedString),
-                        GetStrokeStyle, SetStrokeStyle);
-    result->SetAccessor(String::NewFromUtf8(
-            fGlobal->getIsolate(), "width", String::kInternalizedString),
-                        GetWidth);
-    result->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);
-
-    // Return the result through the current handle scope.
-    return handleScope.Escape(result);
-}
-
-
 // Wraps 'this' in a Javascript object.
 Handle<Object> JsContext::wrap() {
     // Handle scope for temporary handles.
     EscapableHandleScope handleScope(fGlobal->getIsolate());
 
     // Fetch the template for creating JavaScript JsContext wrappers.
     // It only has to be created once, which we do on demand.
     if (gContextTemplate.IsEmpty()) {
-        Handle<ObjectTemplate> raw_template = this->makeContextTemplate();
-        gContextTemplate.Reset(fGlobal->getIsolate(), raw_template);
+        Local<ObjectTemplate> localTemplate = ObjectTemplate::New();
+
+        // Add a field to store the pointer to a JsContext instance.
+        localTemplate->SetInternalFieldCount(1);
+
+        this->addAttributesAndMethods(localTemplate);
+
+        gContextTemplate.Reset(fGlobal->getIsolate(), localTemplate);
     }
     Handle<ObjectTemplate> templ =
             Local<ObjectTemplate>::New(fGlobal->getIsolate(), gContextTemplate);
 
     // Create an empty JsContext wrapper.
     Local<Object> result = templ->NewInstance();
 
     // Wrap the raw C++ pointer in an External so it can be referenced
     // from within JavaScript.
     Handle<External> contextPtr = External::New(fGlobal->getIsolate(), this);
@@ skipping 77 matching lines @@
 
     // It is a function; cast it to a Function.
     Handle<Function> fn_fun = Handle<Function>::Cast(fn_val);
 
     // Store the function in a Persistent handle, since we also want that to
     // remain after this call returns.
     fOnDraw.Reset(fGlobal->getIsolate(), fn_fun);
 
     return true;
 }