dm changes

samplecode/SampleImage.cpp

+/*
+ * Copyright 2015 Google Inc.
+ *
+ * Use of this source code is governed by a BSD-style license that can be
+ * found in the LICENSE file.
+ */
+
+ #include "SampleCode.h"
+ #include "SkPaint.h"
+ #include "SkCanvas.h"
+ #include "SkStream.h"
+ #include "SkImageDecoder.h"
+ #include "Resources.h"
+
+ class ImageView : public SampleView {
+ public:
+        ImageView(const char imageFilename[]) {

[scroggo, 2015/05/18 14:03:59]

nit: Skia uses a four space indent.

Not sure if you've seen it, but here are our code style guidelines:
https://sites.google.com/site/skiadocs/developer-documentation/contributing-c...

They are neither exhaustive nor accurate, but they should give you a good start.

[emmaleeroach, 2015/05/18 20:04:28]

Acknowledged.

+        SkString resourcePath = GetResourcePath(imageFilename);

[scroggo, 2015/05/18 14:03:59]

It threw me off for a second that this is lined up with the function signature.
This should be indented four spaces (although once you move the signature back,
this is in the right place).

[emmaleeroach, 2015/05/18 20:04:28]

Acknowledged.

+        SkImageDecoder* codec = NULL;
+        SkFILEStream stream(resourcePath.c_str());
+        if (stream.isValid()) {
+            codec = SkImageDecoder::Factory(&stream);
+        }
+        if (codec) {
+            stream.rewind();
+            codec->decode(&stream, &fBM, kN32_SkColorType, SkImageDecoder::kDecodePixels_Mode);
+                    SkDELETE(codec);
+                } else {

[scroggo, 2015/05/18 14:03:59]

This should line up with the if statement.

[emmaleeroach, 2015/05/18 20:04:28]

Acknowledged.

+                    fBM.allocN32Pixels(1, 1);
+                    *(fBM.getAddr32(0,0)) = 0xFF0000FF; // red == bad

[scroggo, 2015/05/18 14:03:59]

This is just an example, so it doesn't matter too much, but it's worth
discussing colors.

We have a couple of different types that represent colors: SkColor and SkPMColor
(both are found in SkColor.h, and both are typedefs for uint32_t).

SkColor is platform-independent, and can be represented as a hexadecimal number
that looks like 0xAARRGGBB. This is used for APIs like SkPaint::setColor(),
allowing someone to write the same code to run on multiple platforms.

SkPMColor is the color used for drawing (SkColors will always be converted to
SkPMColor). So the address that getAddr32 points to is an SkPMColor. (Aside: PM
stands for Pre-Multiplied. This means we have multiplied the alpha value by each
component, which is more efficient for blending.) Since your alpha is FF, this
color is premultiplied. Unlike SkColor, SkPMColor has an ordering that can be
determined at compile time. SK_PMCOLOR_BYTE_ORDER specifies the ordering. This
might be red on your build, but we could redefine some values in SkPostConfig.h
(see SK_A32_SHIFT and the macros below) and make it a different color.

There are a couple safe ways to do this so it is the same color regardless of
the order of SkPMColor, which can be found in SkColor.h:

SkPreMultiplyColor(SK_ColorRED)
SkPreMultiplyARGB(0xFF, 0xFF, 0, 0)

Let me know if you want to talk about any of this more.

[scroggo, 2015/05/18 20:43:18]

Yes :)

+                }
+        }
+
+ protected:
+        SkBitmap fBM;

[scroggo, 2015/05/18 14:03:59]

Generally, this should be private unless you want to allow a subclass to access
it. (It is generally better, though, if a subclass needs to access this, to make
it private with a protected method for access.)

+
+        virtual bool onQuery(SkEvent* evt) {

[scroggo, 2015/05/18 14:03:59]

The spacing is wrong for much of this file. Generally, you want to indent four
spaces for all class members, and again for each level of scope.

+        if (SampleCode::TitleQ(*evt)) {
+            SampleCode::TitleR(evt, "ImageView");
+            return true;
+        }
+        return this->INHERITED::onQuery(evt);
+    }
+
+    virtual void onDrawContent(SkCanvas* canvas) {
+        
+        canvas->drawColor(SK_ColorWHITE);
+        
+        SkPaint paint;
+
+        paint.setAntiAlias(true);
+        paint.setTextSize(48);
+        paint.setFilterQuality(kHigh_SkFilterQuality);
+        canvas->save();
+        canvas->drawBitmap( fBM, 50, 50, &paint );
+        canvas->restore();
+
+            paint.setColor(SK_ColorRED);
+            paint.setAntiAlias(true);
+            paint.setStyle(SkPaint::kStroke_Style);
+            paint.setStrokeWidth(10);
+            canvas->drawLine(20, 20, 100, 100, paint);
+    }
+
+ private:
+        typedef SampleView INHERITED;
+
+ };
+
+static SkView* MyFactory() { return new ImageView("yellow_rose.png"); }
+static SkViewRegister reg(MyFactory);