How to make the drawing path smooth when drawing in variable width steps

I created an example drawing application in which the user can draw using the variable width change. So far, the variable stroke drawing path works, but the lines drawn are not smooth. The code I used for this is shown below.

Help me figure out how it has been over the past two days.

Code for drawing a path using a variable stroke width

public class FingerPaint extends GraphicsActivity {

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
        setContentView(new MyView(this));
    }

    public void colorChanged(int color)  {
    }

    public class MyView extends View {

        private static final float STROKE_WIDTH = 5f;    
        private Paint paint = new Paint();
        private Path mPath = new Path();
        ArrayList<Path> mPaths = new ArrayList<Path>();
        ArrayList<Integer> mStrokes = new ArrayList<Integer>();

        private float lastTouchX;
        private float lastTouchY;
        private final RectF dirtyRect = new RectF();
        private int lastStroke = -1;
        int variableWidthDelta = 0;

        private static final float STROKE_DELTA = 0.0001f; // for float comparison
        private static final float STROKE_INCREMENT = 0.01f; // amount to interpolate
        private float currentStroke = STROKE_WIDTH;
        private float targetStroke = STROKE_WIDTH;

        private float mX, mY;
        private static final float TOUCH_TOLERANCE = 4;

        public MyView(Context context)  {
            super(context);

            paint.setAntiAlias(true);
            paint.setDither(true);
            paint.setStyle(Paint.Style.STROKE);
            paint.setStrokeJoin(Paint.Join.ROUND);
            paint.setStrokeCap(Paint.Cap.ROUND);    
            paint.setStrokeWidth(STROKE_WIDTH);
        }

        public void clear() {
            mPath.reset();
            // Repaints the entire view.
            invalidate();
        }

        @Override
        protected void onDraw(Canvas canvas)  {
            for(int i=0; i<mPaths.size();i++) {
                paint.setStrokeWidth(mStrokes.get(i));
                canvas.drawPath(mPaths.get(i), paint);
            }
        }

        @Override
        public boolean onTouchEvent(MotionEvent event) {
            float eventX = event.getX();
            float eventY = event.getY();
            int historySize = event.getHistorySize();

            switch (event.getAction()) {
                case MotionEvent.ACTION_DOWN: {
                    resetDirtyRect(eventX, eventY);
//                  mPath.reset();
                    mPath.moveTo(eventX, eventY);
                    mX = eventX;
                    mY = eventY;
                    break;                  
                }
                case MotionEvent.ACTION_MOVE: {                 
                    if (event.getPressure()>=0.00 && event.getPressure()<0.05) {
                        variableWidthDelta = -2;
                    } else if (event.getPressure()>=0.05 && event.getPressure()<0.10) {
                        variableWidthDelta = -2;
                    } else if (event.getPressure()>=0.10 && event.getPressure()<0.15) {
                        variableWidthDelta = -2;
                    } else if (event.getPressure()>=0.15 && event.getPressure()<0.20) {
                        variableWidthDelta = -2;
                    } else if (event.getPressure()>=0.20 && event.getPressure()<0.25) {
                        variableWidthDelta = -2;
                    } else if (event.getPressure() >= 0.25 && event.getPressure()<0.30) {
                        variableWidthDelta = 1;
                    } else if (event.getPressure() >= 0.30 && event.getPressure()<0.35) {
                        variableWidthDelta = 2;
                    } else if (event.getPressure() >= 0.35 && event.getPressure()<0.40) {
                        variableWidthDelta = 3;
                    } else if (event.getPressure() >= 0.40 && event.getPressure()<0.45) {
                        variableWidthDelta = 4;
                    } else if (event.getPressure() >= 0.45 && event.getPressure()<0.60) {
                        variableWidthDelta = 5;
                    }                                          

                    // if current not roughly equal to target
                    if( Math.abs(targetStroke - currentStroke) > STROKE_DELTA ) 
                    {
                        // move towards target by the increment
                        if( targetStroke > currentStroke)
                        {
                            currentStroke = Math.min(targetStroke, currentStroke + STROKE_INCREMENT);
                        }
                        else
                        {
                            currentStroke = Math.max(targetStroke, currentStroke - STROKE_INCREMENT);
                        }

                    } 
                    mStrokes.add((int) currentStroke);

                    targetStroke = variableWidthDelta;

                    float dx = Math.abs(eventX - mX);
                    float dy = Math.abs(eventY - mY);

                    if (dx >= TOUCH_TOLERANCE || dy >= TOUCH_TOLERANCE) {
                        if(lastStroke != variableWidthDelta) {
                            mPath.lineTo(mX, mY);

                            mPath = new Path();
                            mPath.moveTo(mX,mY);
                            mPaths.add(mPath);
                        }

                        mPath.quadTo(mX, mY, (eventX + mX)/2, (eventY + mY)/2);
                        mX = eventX;
                        mY = eventY;
                    }

                    for (int i = 0; i < historySize; i++) {
                        float historicalX = event.getHistoricalX(i);
                        float historicalY = event.getHistoricalY(i);
                        expandDirtyRect(historicalX, historicalY);
                    }
                    break;
                }
                case MotionEvent.ACTION_UP: {
                    for (int i = 0; i < historySize; i++) {
                        float historicalX = event.getHistoricalX(i);
                        float historicalY = event.getHistoricalY(i);
                        expandDirtyRect(historicalX, historicalY);
                    }
                   mPath.lineTo(mX, mY);                   
                   break;
                }
            }

            // Include half the stroke width to avoid clipping.
            invalidate();

            lastTouchX = eventX;
            lastTouchY = eventY;
            lastStroke = variableWidthDelta;

            return true;
        }

        private void expandDirtyRect(float historicalX, float historicalY) {
            if (historicalX < dirtyRect.left) {
                dirtyRect.left = historicalX;
            }  else if (historicalX > dirtyRect.right) {
                dirtyRect.right = historicalX;
            }
            if (historicalY < dirtyRect.top) {
                dirtyRect.top = historicalY;
            } else if (historicalY > dirtyRect.bottom) {
                dirtyRect.bottom = historicalY;
            }
        }

        /**
         * Resets the dirty region when the motion event occurs.
         */
        private void resetDirtyRect(float eventX, float eventY) {
            // The lastTouchX and lastTouchY were set when the ACTION_DOWN
            // motion event occurred.
            dirtyRect.left = Math.min(lastTouchX, eventX);
            dirtyRect.right = Math.max(lastTouchX, eventX);
            dirtyRect.top = Math.min(lastTouchY, eventY);
            dirtyRect.bottom = Math.max(lastTouchY, eventY);
        }
    }
}

The result of the output I received

enter image description here

The result that I want to achieve

enter image description here

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2 answers

, , , , . mStrokes Float Integer s.

private static final float STROKE_DELTA = 0.0001f; // for float comparison
private static final float STROKE_INCREMENT = 0.01f; // amount to interpolate
private float currentStroke = STROKE_WIDTH;
private float targetStroke = STROKE_WIDTH;

, :

// if current not roughly equal to target
if( Math.abs(targetStroke - currentStroke) > STROKE_DELTA ) {
    // move towards target by the increment
    if( targetStroke > currentStroke )
        currentStroke = Math.min(targetStroke, currentStroke + STROKE_INCREMENT);
    else
        currentStroke = Math.max(targetStroke, currentStroke - STROKE_INCREMENT);
    mPath.lineTo(mX, mY);

    mPath = new Path();
    mPath.moveTo(mX,mY);
    mPaths.add(mPath);
    mStrokes.add(currentStroke);
}

targetStroke, variableWidthDelta.

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