Android - 图像变形效果

Question

在我的 android 应用程序中，我想应用 Photo Warp 中提供的图像 warp 效果和 Photo Deformer应用。为此，我使用了 BitmapMesh。问题是，它没有保存扭曲的图像。每当我触摸图像时，它都会刷新图像并且不会保存我之前扭曲的图像。我想在用户执行扭曲操作时保存该图像。我在这里发布我的代码。在这里，我使用“BitmapMesh” Activity 对图像执行扭曲效果。

请帮我解决这个问题。 谢谢。

代码:

位图网格 Activity :

import android.content.Context;
import android.graphics.Bitmap;
import android.graphics.BitmapFactory;
import android.graphics.Canvas;
import android.graphics.Matrix;
import android.os.Bundle;
import android.util.FloatMath;
import android.view.MotionEvent;
import android.view.View;

public class BitmapMesh extends GraphicsActivity {

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

    private static class SampleView extends View {
        private static final int WIDTH = 20;
        private static final int HEIGHT = 20;
        private static final int COUNT = (WIDTH + 1) * (HEIGHT + 1);

        private final Bitmap mBitmap;
        private final float[] mVerts = new float[COUNT * 2];
        private final float[] mOrig = new float[COUNT * 2];

        private final Matrix mMatrix = new Matrix();
        private final Matrix mInverse = new Matrix();

        private static void setXY(float[] array, int index, float x, float y) {
            array[index * 2 + 0] = x;
            array[index * 2 + 1] = y;
        }

        public SampleView(Context context) {
            super(context);
            setFocusable(true);

            mBitmap = BitmapFactory.decodeResource(getResources(),
                    R.drawable.image1);

            float w = mBitmap.getWidth();
            float h = mBitmap.getHeight();
            // construct our mesh
            int index = 0;
            for (int y = 0; y <= HEIGHT; y++) {
                float fy = h * y / HEIGHT;
                for (int x = 0; x <= WIDTH; x++) {
                    float fx = w * x / WIDTH;
                    setXY(mVerts, index, fx, fy);
                    setXY(mOrig, index, fx, fy);
                    index += 1;
                }
            }

            mMatrix.setTranslate(10, 10);
            mMatrix.invert(mInverse);
        }

        @Override
        protected void onDraw(Canvas canvas) {
            canvas.drawColor(0xFFCCCCCC);

            canvas.concat(mMatrix);
            canvas.drawBitmapMesh(mBitmap, WIDTH, HEIGHT, mVerts, 0, null, 0,
                    null);
        }

        private void warp(float cx, float cy) {
            final float K = 10000;
            float[] src = mOrig;
            float[] dst = mVerts;
            for (int i = 0; i < COUNT * 2; i += 2) {
                float x = src[i + 0];
                float y = src[i + 1];
                float dx = cx - x;
                float dy = cy - y;
                float dd = dx * dx + dy * dy;
                float d = FloatMath.sqrt(dd);
                float pull = K / (dd + 0.000001f);

                pull /= (d + 0.000001f);
                // android.util.Log.d("skia", "index " + i + " dist=" + d +
                // " pull=" + pull);

                if (pull >= 1) {
                    dst[i + 0] = cx;
                    dst[i + 1] = cy;
                } else {
                    dst[i + 0] = x + dx * pull;
                    dst[i + 1] = y + dy * pull;
                }
            }

        }

        private int mLastWarpX = -9999; // don't match a touch coordinate
        private int mLastWarpY;

        @Override
        public boolean onTouchEvent(MotionEvent event) {
            float[] pt = { event.getX(), event.getY() };
            mInverse.mapPoints(pt);

            int x = (int) pt[0];
            int y = (int) pt[1];
            if (mLastWarpX != x || mLastWarpY != y) {
                mLastWarpX = x;
                mLastWarpY = y;
                warp(pt[0], pt[1]);
                invalidate();
            }
            return true;
        }
    }
}

图形 Activity :

import android.app.Activity;
import android.os.Bundle;
import android.view.View;
import android.view.ViewGroup;

class GraphicsActivity extends Activity {
    // set to true to test Picture
    private static final boolean TEST_PICTURE = false;

    @Override
    protected void onCreate(Bundle savedInstanceState) {
        super.onCreate(savedInstanceState);
    }

    @Override
    public void setContentView(View view) {
        if (TEST_PICTURE) {
            ViewGroup vg = new PictureLayout(this);
            vg.addView(view);
            view = vg;
        }

        super.setContentView(view);
    }
}

图片布局.java

import android.content.Context;
import android.graphics.Canvas;
import android.graphics.Picture;
import android.graphics.Rect;
import android.graphics.drawable.Drawable;
import android.util.AttributeSet;
import android.view.View;
import android.view.ViewGroup;
import android.view.ViewParent;

class PictureLayout extends ViewGroup {
    private final Picture mPicture = new Picture();

    public PictureLayout(Context context) {
        super(context);
    }

    public PictureLayout(Context context, AttributeSet attrs) {
        super(context, attrs);
    }

    @Override
    public void addView(View child) {
        if (getChildCount() > 1) {
            throw new IllegalStateException(
                    "PictureLayout can host only one direct child");
        }

        super.addView(child);
    }

    @Override
    public void addView(View child, int index) {
        if (getChildCount() > 1) {
            throw new IllegalStateException(
                    "PictureLayout can host only one direct child");
        }

        super.addView(child, index);
    }

    @Override
    public void addView(View child, LayoutParams params) {
        if (getChildCount() > 1) {
            throw new IllegalStateException(
                    "PictureLayout can host only one direct child");
        }

        super.addView(child, params);
    }

    @Override
    public void addView(View child, int index, LayoutParams params) {
        if (getChildCount() > 1) {
            throw new IllegalStateException(
                    "PictureLayout can host only one direct child");
        }

        super.addView(child, index, params);
    }

    @Override
    protected LayoutParams generateDefaultLayoutParams() {
        return new LayoutParams(LayoutParams.MATCH_PARENT,
                LayoutParams.MATCH_PARENT);
    }

    @Override
    protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
        final int count = getChildCount();

        int maxHeight = 0;
        int maxWidth = 0;

        for (int i = 0; i < count; i++) {
            final View child = getChildAt(i);
            if (child.getVisibility() != GONE) {
                measureChild(child, widthMeasureSpec, heightMeasureSpec);
            }
        }

        maxWidth += getPaddingLeft() + getPaddingRight();
        maxHeight += getPaddingTop() + getPaddingBottom();

        Drawable drawable = getBackground();
        if (drawable != null) {
            maxHeight = Math.max(maxHeight, drawable.getMinimumHeight());
            maxWidth = Math.max(maxWidth, drawable.getMinimumWidth());
        }

        setMeasuredDimension(resolveSize(maxWidth, widthMeasureSpec),
                resolveSize(maxHeight, heightMeasureSpec));
    }

    private void drawPict(Canvas canvas, int x, int y, int w, int h, float sx,
            float sy) {
        canvas.save();
        canvas.translate(x, y);
        canvas.clipRect(0, 0, w, h);
        canvas.scale(0.5f, 0.5f);
        canvas.scale(sx, sy, w, h);
        canvas.drawPicture(mPicture);
        canvas.restore();
    }

    @Override
    protected void dispatchDraw(Canvas canvas) {
        super.dispatchDraw(mPicture.beginRecording(getWidth(), getHeight()));
        mPicture.endRecording();

        int x = getWidth() / 2;
        int y = getHeight() / 2;

        if (false) {
            canvas.drawPicture(mPicture);
        } else {
            drawPict(canvas, 0, 0, x, y, 1, 1);
            drawPict(canvas, x, 0, x, y, -1, 1);
            drawPict(canvas, 0, y, x, y, 1, -1);
            drawPict(canvas, x, y, x, y, -1, -1);
        }
    }

    @Override
    public ViewParent invalidateChildInParent(int[] location, Rect dirty) {
        location[0] = getLeft();
        location[1] = getTop();
        dirty.set(0, 0, getWidth(), getHeight());
        return getParent();
    }

    @Override
    protected void onLayout(boolean changed, int l, int t, int r, int b) {
        final int count = super.getChildCount();

        for (int i = 0; i < count; i++) {
            final View child = getChildAt(i);
            if (child.getVisibility() != GONE) {
                final int childLeft = getPaddingLeft();
                final int childTop = getPaddingTop();
                child.layout(childLeft, childTop,
                        childLeft + child.getMeasuredWidth(),
                        childTop + child.getMeasuredHeight());

            }
        }
    }
}

Answer 1

//Little changes in this piece of code
  float[] dst; //Global

public SampleView(Context context) {
        super(context);
        setFocusable(true);

        mBitmap = BitmapFactory.decodeResource(getResources(),
                R.drawable.image1);

        float w = mBitmap.getWidth();
        float h = mBitmap.getHeight();
        // construct our mesh
        int index = 0;
        for (int y = 0; y <= HEIGHT; y++) {
            float fy = h * y / HEIGHT;
            for (int x = 0; x <= WIDTH; x++) {
                float fx = w * x / WIDTH;
                setXY(mVerts, index, fx, fy);
                setXY(mOrig, index, fx, fy);
                index += 1;

                dst=mVerts;//Assign dst here just once

            }
        }

        mMatrix.setTranslate(10, 10);
        mMatrix.invert(mInverse);
    }

    @Override
    protected void onDraw(Canvas canvas) {
        canvas.drawColor(0xFFCCCCCC);

        canvas.concat(mMatrix);
        canvas.drawBitmapMesh(mBitmap, WIDTH, HEIGHT, mVerts, 0, null, 0,
                null);
    }

    private void warp(float cx, float cy) {
        final float K = 10000;
        float[] src = dst; //now you are applying wrap effect on the last effected pixels

        for (int i = 0; i < COUNT * 2; i += 2) {
            float x = src[i + 0];
            float y = src[i + 1];
            float dx = cx - x;
            float dy = cy - y;
            float dd = dx * dx + dy * dy;
            float d = FloatMath.sqrt(dd);
            float pull = K / (dd + 0.000001f);

            pull /= (d + 0.000001f);
            // android.util.Log.d("skia", "index " + i + " dist=" + d +
            // " pull=" + pull);

            if (pull >= 1) {
                dst[i + 0] = cx;
                dst[i + 1] = cy;
            } else {
                dst[i + 0] = x + dx * pull;
                dst[i + 1] = y + dy * pull;
            }
        }

    }