Revert of Remove unused (by clients) SkUnitMapper (https://codereview.chromium.org/283273002/) (https://codereview.chromium.org/288343009/)

Reason for revert:
required blink change failed to land

Original issue's description:
> Remove unused (by clients) SkUnitMapper (https://codereview.chromium.org/283273002/)
>
> This reverts commit dd50c83b5b34dab3a077741861b50ed1f2bc6b8f.
>
> BUG=skia:
>
> Committed: http://code.google.com/p/skia/source/detail?r=14830

R=scroggo@google.com, reed@google.com
TBR=reed@google.com, scroggo@google.com
NOTREECHECKS=true
NOTRY=true
BUG=skia:

Author: reed@chromium.org

Review URL: https://codereview.chromium.org/296823008

git-svn-id: http://skia.googlecode.com/svn/trunk@14838 2bbb7eff-a529-9590-31e7-b0007b416f81

1 files changed, 172 insertions, 0 deletions

diff --git a/samplecode/SampleUnitMapper.cpp b/samplecode/SampleUnitMapper.cpp
new file mode 100644
index 0000000000..db9af09f38
--- /dev/null
+++ b/samplecode/SampleUnitMapper.cpp
@@ -0,0 +1,172 @@
+
+/*
+ * Copyright 2011 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 "SkView.h"
+#include "SkCanvas.h"
+#include "SkDevice.h"
+#include "SkPaint.h"
+#include "SkUnitMappers.h"
+#include "SkCubicInterval.h"
+
+#include "SkWidgetViews.h"
+
+static SkStaticTextView* make_textview(SkView* parent,
+                                       const SkRect& bounds,
+                                       const SkPaint& paint) {
+    SkStaticTextView* view = new SkStaticTextView;
+    view->setMode(SkStaticTextView::kFixedSize_Mode);
+    view->setPaint(paint);
+    view->setVisibleP(true);
+    view->setSize(bounds.width(), bounds.height());
+    view->setLoc(bounds.fLeft, bounds.fTop);
+    parent->attachChildToFront(view)->unref();
+    return view;
+}
+
+static void set_scalar(SkStaticTextView* view, SkScalar value) {
+    SkString str;
+    str.appendScalar(value);
+    view->setText(str);
+}
+
+class UnitMapperView : public SampleView {
+    SkPoint fPts[4];
+    SkMatrix fMatrix;
+    SkStaticTextView* fViews[4];
+
+    void setViews() {
+        set_scalar(fViews[0], fPts[1].fX);
+        set_scalar(fViews[1], fPts[1].fY);
+        set_scalar(fViews[2], fPts[2].fX);
+        set_scalar(fViews[3], fPts[2].fY);
+    }
+
+public:
+    UnitMapperView() {
+        fPts[0].set(0, 0);
+        fPts[1].set(SK_Scalar1 / 3, SK_Scalar1 / 3);
+        fPts[2].set(SK_Scalar1 * 2 / 3, SK_Scalar1 * 2 / 3);
+        fPts[3].set(SK_Scalar1, SK_Scalar1);
+
+        fMatrix.setScale(SK_Scalar1 * 200, -SK_Scalar1 * 200);
+        fMatrix.postTranslate(SkIntToScalar(100), SkIntToScalar(300));
+
+        SkRect r = {
+            SkIntToScalar(350), SkIntToScalar(100),
+            SkIntToScalar(500), SkIntToScalar(130)
+        };
+        SkPaint paint;
+        paint.setAntiAlias(true);
+        paint.setTextSize(SkIntToScalar(25));
+        for (int i = 0; i < 4; i++) {
+            fViews[i] = make_textview(this, r, paint);
+            r.offset(0, r.height());
+        }
+        this->setViews();
+    }
+
+protected:
+    // overrides from SkEventSink
+    virtual bool onQuery(SkEvent* evt) {
+        if (SampleCode::TitleQ(*evt)) {
+            SampleCode::TitleR(evt, "UnitMapper");
+            return true;
+        }
+        return this->INHERITED::onQuery(evt);
+    }
+
+    virtual void onDrawContent(SkCanvas* canvas) {
+        SkPaint paint;
+        paint.setAntiAlias(true);
+        paint.setColor(0xFF8888FF);
+
+        SkRect r = { 0, 0, SK_Scalar1, SK_Scalar1 };
+
+        canvas->concat(fMatrix);
+        canvas->drawRect(r, paint);
+
+        paint.setColor(SK_ColorBLACK);
+        paint.setStyle(SkPaint::kStroke_Style);
+        paint.setStrokeWidth(0);
+        paint.setStrokeCap(SkPaint::kRound_Cap);
+
+        SkPath path;
+        path.moveTo(fPts[0]);
+        path.cubicTo(fPts[1], fPts[2], fPts[3]);
+        canvas->drawPath(path, paint);
+
+        paint.setColor(SK_ColorRED);
+        paint.setStrokeWidth(0);
+        canvas->drawLine(0, 0, SK_Scalar1, SK_Scalar1, paint);
+
+        paint.setColor(SK_ColorBLUE);
+        paint.setStrokeWidth(SK_Scalar1 / 60);
+        for (int i = 0; i < 50; i++) {
+            SkScalar x = i * SK_Scalar1 / 49;
+            canvas->drawPoint(x, SkEvalCubicInterval(&fPts[1], x), paint);
+        }
+
+        paint.setStrokeWidth(SK_Scalar1 / 20);
+        paint.setColor(SK_ColorGREEN);
+        canvas->drawPoints(SkCanvas::kPoints_PointMode, 2, &fPts[1], paint);
+    }
+
+    bool invertPt(SkScalar x, SkScalar y, SkPoint* result) {
+        if (NULL == result)
+            return true;
+
+        SkMatrix m;
+        if (!fMatrix.invert(&m)) {
+            return false;
+        }
+
+        m.mapXY(x, y, result);
+        return true;
+    }
+
+    int hittest(SkScalar x, SkScalar y) {
+        SkPoint target = { x, y };
+        SkPoint pts[2] = { fPts[1], fPts[2] };
+        fMatrix.mapPoints(pts, 2);
+        for (int i = 0; i < 2; i++) {
+            if (SkPoint::Distance(pts[i], target) < SkIntToScalar(4)) {
+                return i + 1;
+            }
+        }
+        return -1;
+    }
+
+    virtual SkView::Click* onFindClickHandler(SkScalar x, SkScalar y, unsigned) SK_OVERRIDE {
+        fDragIndex = hittest(x, y);
+        return fDragIndex >= 0 ? new Click(this) : NULL;
+    }
+
+    virtual bool onClick(Click* click) {
+        if (fDragIndex >= 0) {
+            if (!invertPt(click->fCurr.fX, click->fCurr.fY,
+                          &fPts[fDragIndex])) {
+                return false;
+            }
+
+            this->setViews();
+            this->inval(NULL);
+            return true;
+        }
+        return false;
+    }
+
+private:
+    int fDragIndex;
+
+    typedef SampleView INHERITED;
+};
+
+//////////////////////////////////////////////////////////////////////////////
+
+static SkView* MyFactory() { return new UnitMapperView; }
+static SkViewRegister reg(MyFactory);