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标题: 分享一段 Android图片处理代码 [打印本页]

作者: 张振宁 时间: 2011-12-22 16:26
标题: 分享一段 Android图片处理代码
/** 放大缩小
   * @param bgimage
   * @param newWidth
   * @param newHeight
   * @return
   */
public Bitmap ZoomImage(Bitmap src, Float newWidth, Float newHeight) {
int width = src.getWidth();
int height = src.getHeight();
Matrix matrix = new Matrix();
float scaleWidth  = newWidth  / width;
float scaleHeight = newHeight / height;
matrix.postScale(scaleWidth, scaleHeight);
Bitmap bitmap = Bitmap.createBitmap(src, 0, 0, width, height, matrix, true);
return bitmap;
}

/** 旋转图片返回传入点旋转后的位置
   * @param 图片大小/中点/旋转角度
   * @return 旋转后中点位置
   */
public Vector2D rota(Vector2D bitmapSize, Vector2D midPoint, float angle){
float w = bitmapSize.x;
float h = bitmapSize.y;
angle = (float)Math.toRadians(angle);
Vector<Vector2D> vec = new Vector<Vector2D>();
//创建矩形的四个顶点
Vector2D point1 = new Vector2D(-midPoint.x,-midPoint.y);
Vector2D point2 = new Vector2D(-midPoint.x + w,-midPoint.y);
Vector2D point3 = new Vector2D(-midPoint.x + w,-midPoint.y + h);
Vector2D point4 = new Vector2D(-midPoint.x,-midPoint.y + h);
//旋转后顶点位置
point1.setAngle(point1.getAngle()+angle);
point2.setAngle(point2.getAngle()+angle);
point3.setAngle(point3.getAngle()+angle);
point4.setAngle(point4.getAngle()+angle);
//取出左上顶点
vec.addElement(point1);
vec.addElement(point2);
vec.addElement(point3);
vec.addElement(point4);
Vector2D newOrigin = new Vector2D(0,0);
for (int i = 0; i < vec.size(); i++) {
      Vector2D tmp = vec.elementAt(i);
      if(newOrigin.getX()>tmp.getX()){
newOrigin.setX(tmp.getX());
      }
      if(newOrigin.getY()>tmp.getY()){
newOrigin.setY(tmp.getY());
      ｝
}
return newOrigin;
}
//单张图片旋转
public Bitmap draw(){
float angle = (float)Math.toDegrees(velocity.getAngle())+90;
Matrix ma = new Matrix();
ma.setRotate(angle);
mid = GameView.img.rota(new Vector2D(imgSrc.getWidth(),imgSrc.getHeight()), new Vector2D(imgSrc.getWidth()/2,imgSrc.getHeight()/2), angle);
return Bitmap.createBitmap(imgSrc,0,0,imgSrc.getWidth(),imgSrc.getHeight(),ma,true);
}
Vector2D 向量类
public class Vector2D {
public float x;
public float y;
//-------------------------------------------------
public Vector2D() {
super();
}
public Vector2D(float x, float y) {
this.x = x;
this.y = y;
}
//-------------------------------------------------
public Vector2D clone() {
return new Vector2D(x, y);
}
//归零
public Vector2D zero(){
x = 0;
y = 0;
return this;
}
//是否为0
public boolean isZero(){
return x == 0 && y == 0;
}
/** 取出两点间距离*/
public float getLength(){
return (float)Math.sqrt(getLengthSQ());
}
/** 取出X Y的平方和*/
public float getLengthSQ(){
return x * x + y * y;
}
/** 设置长度*/
public void setLength(float value){
float a = getAngle();
x = (float)Math.cos(a) * value;
y = (float)Math.sin(a) * value;
}
/** 设置角度*/
public void setAngle(float value){
float len = getLength();
x = (float)Math.cos(value) * len;
y = (float)Math.sin(value) * len;
}
public float getAngle(){
return (float)Math.atan2(y, x);
}
/** 规范化*/
public Vector2D normalize(){
if (getLength() == 0) {
x = 1;
return this;
}
float len = getLength();
x /=  len;
y /=  len;
return this;
}
/** 取最小值*/
public Vector2D truncate(float max){
setLength(Math.min(max,getLength()));
return this;
}
/** 取负值*/
public Vector2D reverse(){
x =  -  x;
y =  -  y;
return this;
}
public boolean isNormalized(){
return getLength()==1.0;
}

public float dotProd(Vector2D v2){
return x * v2.getX() + y * v2.getY();
}

public float crossProd(Vector2D v2) {
return x * v2.getY() - y * v2.getX();
}
public static float angleBetween(Vector2D v1, Vector2D v2) {
if (! v1.isNormalized()) {
v1 = v1.clone().normalize();
}
if (! v2.isNormalized()) {
v2 = v2.clone().normalize();
}
return (float)Math.acos(v1.dotProd(v2));
}

public int sign(Vector2D v2) {
return getPerp().dotProd(v2) < 0 ? -1 : 1;
}

public Vector2D getPerp() {
return new Vector2D(-y, x);
}

public float dist(Vector2D v2) {
return (float)Math.sqrt(distSQ(v2));
}

public float distSQ(Vector2D v2) {
float dx = v2.getX() - x;
float dy = v2.getY() - y;
return dx * dx + dy * dy;
}

public Vector2D add(Vector2D v2) {
return new Vector2D(x + v2.getX(), y + v2.getY());
}

public Vector2D subtract(Vector2D v2){
return new Vector2D(x - v2.getX(), y - v2.getY());
}

public Vector2D multiply(float value) {
return new Vector2D(x * value, y * value);
}
/** 分份*/
public Vector2D divide(float value) {
return new Vector2D(x / value, y / value);
}
/** 查看两点坐标是否相同*/
public boolean equals(Vector2D v2) {
return x == v2.getX() && y == v2.getY();
}

public String toString() {
return "[Vector2D (x:" + x + ", y:" + y + ")]";
}

//-------------------------------------------------
public float getX() {
return x;
}
public void setX(float x) {
this.x = x;
}
public float getY() {
return y;
}
public void setY(float y) {
this.y = y;
}
}

作者: 房宝彬 时间: 2011-12-22 17:15
我只能说，我看不懂{:soso_e127:}

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