Android处理图片

/* 定义DisplayMetrics对象 */

DisplayMetrics dm = new DisplayMetrics();



/* 取得窗口属性 */

getWindowManager().getDefaultDisplay().getMetrics(dm);

1.基本图像绘制

/* 创建两个图片对象 */

Bitmap mBitQQ = null;

Bitmap mBitDestTop = null;

int miDTX = 0;

public GameView(Context context)

{

super(context);



mPaint = new Paint();



miDTX = 0;



/* 从资源文件中装载图片 */

//getResources()->得到Resources

//getDrawable()->得到资源中的Drawable对象，参数为资源索引ID

//getBitmap()->得到Bitmap

mBitQQ = ((BitmapDrawable) getResources().getDrawable(R.drawable.qq)).getBitmap();



mBitDestTop = ((BitmapDrawable) getResources().getDrawable(R.drawable.desktop)).getBitmap();



new Thread(this).start();

}



public void onDraw(Canvas canvas)

{

super.onDraw(canvas);



/* 清屏效果 */

canvas.drawColor(Color.GRAY);



/* 在屏幕(0,0)处绘制图片mBitQQ */

GameView.drawImage(canvas, mBitQQ, 0, 0);



/* 在制定位置按指定裁剪的渔区进行绘制 */

//getWidth()->得到图片的宽度

//getHeight()->得到图片的高度

GameView.drawImage(canvas, mBitDestTop, miDTX, mBitQQ.getHeight(), mBitDestTop.getWidth(), mBitDestTop.getHeight()/2, 0, 0);



}



2。旋转图片

public void onDraw(Canvas canvas)

{

super.onDraw(canvas);



/* 重置mMatrix */

mMatrix.reset();



/* 设置旋转 */

mMatrix.setRotate(Angle);



/* 按mMatrix得旋转构建新的Bitmap */

Bitmap mBitQQ2 = Bitmap.createBitmap(mBitQQ, 0, 0, BitQQwidth,BitQQheight, mMatrix, true);

/* 绘制旋转之后的图片 */

GameView.drawImage(canvas, mBitQQ2, (320-BitQQwidth)/2, 10);



mBitQQ2 = null;

}

3。缩放图片

public void onDraw(Canvas canvas)

{

super.onDraw(canvas);



/* 重置mMatrix */

mMatrix.reset();



/* 设置缩放 */

mMatrix.postScale(Scale,Scale);



/* 按mMatrix得旋转构建新的Bitmap */

Bitmap mBitQQ2 = Bitmap.createBitmap(mBitQQ, 0, 0, BitQQwidth,BitQQheight, mMatrix, true);

/* 绘制旋转之后的图片 */

GameView.drawImage(canvas, mBitQQ2, (320-BitQQwidth)/2, 10);



mBitQQ2 = null;

}

4。混合渲染

/* 得到图片的宽度和高度 */

BitQQwidth = mBitQQ.getWidth();

BitQQheight = mBitQQ.getHeight();



/* 创建BitmapShader对象 */

mBitmapShader = new BitmapShader(mBitQQ,Shader.TileMode.REPEAT,Shader.TileMode.MIRROR);



/* 创建LinearGradient并设置渐变的颜色数组 */

mLinearGradient = new LinearGradient(0,0,100,100,

new int[]{Color.RED,Color.GREEN,Color.BLUE,Color.WHITE},

null,Shader.TileMode.REPEAT);

/* 这里笔者理解为“混合渲染”--大家可以有自己的理解，能明白这个意思就好*/

mComposeShader = new ComposeShader(mBitmapShader,mLinearGradient,PorterDuff.Mode.DARKEN);



/* 构建RadialGradient对象，设置半径的属性 */

//这里使用了BitmapShader和LinearGradient进行混合

//当然也可以使用其他的组合

//混合渲染的模式很多，可以根据自己需要来选择

mRadialGradient = new RadialGradient(50,200,50,

new int[]{Color.GREEN,Color.RED,Color.BLUE,Color.WHITE},

null,Shader.TileMode.REPEAT);

/* 构建SweepGradient对象 */

mSweepGradient = new SweepGradient(30,30,new int[]{Color.GREEN,Color.RED,Color.BLUE,Color.WHITE},null);

mPaint = new Paint();



/* 开启线程 */

new Thread(this).start();

}



public void onDraw(Canvas canvas)

{

super.onDraw(canvas);



//将图片裁剪为椭圆形

/* 构建ShapeDrawable对象并定义形状为椭圆 */

mShapeDrawableQQ = new ShapeDrawable(new OvalShape());

/* 设置要绘制的椭圆形的东西为ShapeDrawable图片 */

mShapeDrawableQQ.getPaint().setShader(mBitmapShader);



/* 设置显示区域 */

mShapeDrawableQQ.setBounds(0,0, BitQQwidth, BitQQheight);



/* 绘制ShapeDrawableQQ */

mShapeDrawableQQ.draw(canvas);



//绘制渐变的矩形

mPaint.setShader(mLinearGradient);

canvas.drawRect(BitQQwidth, 0, 320, 156, mPaint);



//显示混合渲染效果

mPaint.setShader(mComposeShader);

canvas.drawRect(0, 300, BitQQwidth, 300+BitQQheight, mPaint);



//绘制环形渐变

mPaint.setShader(mRadialGradient);

canvas.drawCircle(50, 200, 50, mPaint);



//绘制梯度渐变

mPaint.setShader(mSweepGradient);

canvas.drawRect(150, 160, 300, 300, mPaint);



}

5。图片水纹处理

public class GameView extends View implements Runnable

{

int BACKWIDTH;

int BACKHEIGHT;

short[] buf2;

short[] buf1;

int[] Bitmap2;

int[] Bitmap1;



public GameView(Context context)

{

super(context);



/* 装载图片 */

Bitmap image = BitmapFactory.decodeResource(this.getResources(),R.drawable.qq);

BACKWIDTH = image.getWidth();

BACKHEIGHT = image.getHeight();



buf2 = new short[BACKWIDTH * BACKHEIGHT];

buf1 = new short[BACKWIDTH * BACKHEIGHT];

Bitmap2 = new int[BACKWIDTH * BACKHEIGHT];

Bitmap1 = new int[BACKWIDTH * BACKHEIGHT];

/* 加载图片的像素到数组中 */

image.getPixels(Bitmap1, 0, BACKWIDTH, 0, 0, BACKWIDTH, BACKHEIGHT);



new Thread(this).start();

}





void DropStone(int x,// x坐标

int y,// y坐标

int stonesize,// 波源半径

int stoneweight)// 波源能量

{

for (int posx = x - stonesize; posx < x + stonesize; posx++)

for (int posy = y - stonesize; posy < y + stonesize; posy++)

if ((posx - x) * (posx - x) + (posy - y) * (posy - y) < stonesize * stonesize)

buf1[BACKWIDTH * posy + posx] = (short) -stoneweight;

}





void RippleSpread()

{

for (int i = BACKWIDTH; i < BACKWIDTH * BACKHEIGHT - BACKWIDTH; i++)

{

// 波能扩散

buf2[i] = (short) (((buf1[i - 1] + buf1[i + 1] + buf1[i - BACKWIDTH] + buf1[i + BACKWIDTH]) >> 1) - buf2[i]);

// 波能衰减

buf2[i] -= buf2[i] >> 5;

}

// 交换波能数据缓冲区

short[] ptmp = buf1;

buf1 = buf2;

buf2 = ptmp;

}

/* 渲染你水纹效果 */

void render()

{

int xoff, yoff;

int k = BACKWIDTH;

for (int i = 1; i < BACKHEIGHT - 1; i++)

{

for (int j = 0; j < BACKWIDTH; j++)

{

// 计算偏移量

xoff = buf1[k - 1] - buf1[k + 1];

yoff = buf1[k - BACKWIDTH] - buf1[k + BACKWIDTH];

// 判断坐标是否在窗口范围内

if ((i + yoff) < 0)

{

k++;

continue;

}

if ((i + yoff) > BACKHEIGHT)

{

k++;

continue;

}

if ((j + xoff) < 0)

{

k++;

continue;

}

if ((j + xoff) > BACKWIDTH)

{

k++;

continue;

}

// 计算出偏移象素和原始象素的内存地址偏移量

int pos1, pos2;

pos1 = BACKWIDTH * (i + yoff) + (j + xoff);

pos2 = BACKWIDTH * i + j;

Bitmap2[pos2++] = Bitmap1[pos1++];

k++;

}

}

}



public void onDraw(Canvas canvas)

{

super.onDraw(canvas);



/* 绘制经过处理的图片效果 */

canvas.drawBitmap(Bitmap2, 0, BACKWIDTH, 0, 0, BACKWIDTH, BACKHEIGHT, false, null);

}



// 触笔事件

public boolean onTouchEvent(MotionEvent event)

{



return true;

}

// 按键按下事件

public boolean onKeyDown(int keyCode, KeyEvent event)

{

return true;

}

// 按键弹起事件

public boolean onKeyUp(int keyCode, KeyEvent event)

{

DropStone(BACKWIDTH/2, BACKHEIGHT/2, 10, 30);

return false;

}

public boolean onKeyMultiple(int keyCode, int repeatCount, KeyEvent event)

{

return true;

}



/**

* 线程处理

*/

public void run()

{

while (!Thread.currentThread().isInterrupted())

{

try

{

Thread.sleep(50);

}

catch (InterruptedException e)

{

Thread.currentThread().interrupt();

}

RippleSpread();

render();

//使用postInvalidate可以直接在线程中更新界面

postInvalidate();

}

}

}