skia2/include/views/SkTouchGesture.h
Brian Salomon 88d99df31f [Viewer] Preserve gesture transformation matrix on slide/backend change
Change-Id: I417fb9b6d6b7c95884dff6871731883fe3736437
Reviewed-on: https://skia-review.googlesource.com/91460
Reviewed-by: Brian Osman <brianosman@google.com>
Commit-Queue: Brian Salomon <bsalomon@google.com>
2018-01-05 18:18:39 +00:00

87 lines
2.2 KiB
C++

/*
* Copyright 2011 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#ifndef SkTouchGesture_DEFINED
#define SkTouchGesture_DEFINED
#include "../private/SkTDArray.h"
#include "SkMatrix.h"
struct SkFlingState {
SkFlingState() : fActive(false) {}
bool isActive() const { return fActive; }
void stop() { fActive = false; }
void reset(float sx, float sy);
bool evaluateMatrix(SkMatrix* matrix);
private:
SkPoint fDirection;
SkScalar fSpeed0;
double fTime0;
bool fActive;
};
class SkTouchGesture {
public:
SkTouchGesture();
~SkTouchGesture();
void touchBegin(void* owner, float x, float y);
void touchMoved(void* owner, float x, float y);
void touchEnd(void* owner);
void reset();
void resetTouchState();
bool isActive() { return fFlinger.isActive(); }
void stop() { fFlinger.stop(); }
bool isBeingTouched() { return kEmpty_State != fState; }
const SkMatrix& localM();
const SkMatrix& globalM() const { return fGlobalM; }
void setTransLimit(const SkRect& contentRect, const SkRect& windowRect,
const SkMatrix& preTouchM);
private:
enum State {
kEmpty_State,
kTranslate_State,
kZoom_State,
};
struct Rec {
void* fOwner;
float fStartX, fStartY;
float fPrevX, fPrevY;
float fLastX, fLastY;
float fPrevT, fLastT;
};
SkTDArray<Rec> fTouches;
State fState;
SkMatrix fLocalM, fGlobalM, fPreTouchM;
SkFlingState fFlinger;
double fLastUpMillis;
SkPoint fLastUpP;
// The following rects are used to limit the translation so the content never leaves the window
SkRect fContentRect, fWindowRect;
bool fIsTransLimited = false;
void limitTrans(); // here we only limit the translation with respect to globalM
void flushLocalM();
int findRec(void* owner) const;
void appendNewRec(void* owner, float x, float y);
float computePinch(const Rec&, const Rec&);
float limitTotalZoom(float scale) const;
bool handleDblTap(float, float);
};
#endif