/*
* Copyright (C) 2006 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package android.graphics;
/**
* Rect holds four integer coordinates for a rectangle. The rectangle is
* represented by the coordinates of its 4 edges (left, top, right bottom).
* These fields can be accessed directly. Use width() and height() to retrieve
* the rectangle's width and height. Note: most methods do not check to see that
* the coordinates are sorted correctly (i.e. left <= right and top <= bottom).
*/
public final class Rect {
public int left;
public int top;
public int right;
public int bottom;
/**
* Create a new empty Rect. All coordinates are initialized to 0.
*/
public Rect() {
}
/**
* Create a new rectangle with the specified coordinates. Note: no range
* checking is performed, so the caller must ensure that left <= right and
* top <= bottom.
*
* @param left
* The X coordinate of the left side of the rectagle
* @param top
* The Y coordinate of the top of the rectangle
* @param right
* The X coordinate of the right side of the rectagle
* @param bottom
* The Y coordinate of the bottom of the rectangle
*/
public Rect(int left, int top, int right, int bottom) {
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
/**
* Create a new rectangle, initialized with the values in the specified
* rectangle (which is left unmodified).
*
* @param r
* The rectangle whose coordinates are copied into the new
* rectangle.
*/
public Rect(Rect r) {
left = r.left;
top = r.top;
right = r.right;
bottom = r.bottom;
}
@Override
public boolean equals(Object obj) {
Rect r = (Rect) obj;
if (r != null) {
return left == r.left && top == r.top && right == r.right && bottom == r.bottom;
}
return false;
}
@Override
public String toString() {
StringBuilder sb = new StringBuilder(32);
sb.append("Rect(");
sb.append(left);
sb.append(", ");
sb.append(top);
sb.append(" - ");
sb.append(right);
sb.append(", ");
sb.append(bottom);
sb.append(")");
return sb.toString();
}
/**
* Return a string representation of the rectangle in a compact form.
*/
public String toShortString() {
return toShortString(new StringBuilder(32));
}
/**
* Return a string representation of the rectangle in a compact form.
*
* @hide
*/
public String toShortString(StringBuilder sb) {
sb.setLength(0);
sb.append('[');
sb.append(left);
sb.append(',');
sb.append(top);
sb.append("][");
sb.append(right);
sb.append(',');
sb.append(bottom);
sb.append(']');
return sb.toString();
}
/**
* Returns true if the rectangle is empty (left >= right or top >= bottom)
*/
public final boolean isEmpty() {
return left >= right || top >= bottom;
}
/**
* @return the rectangle's width. This does not check for a valid rectangle
* (i.e. left <= right) so the result may be negative.
*/
public final int width() {
return right - left;
}
/**
* @return the rectangle's height. This does not check for a valid rectangle
* (i.e. top <= bottom) so the result may be negative.
*/
public final int height() {
return bottom - top;
}
/**
* @return the horizontal center of the rectangle. If the computed value is
* fractional, this method returns the largest integer that is less
* than the computed value.
*/
public final int centerX() {
return (left + right) >> 1;
}
/**
* @return the vertical center of the rectangle. If the computed value is
* fractional, this method returns the largest integer that is less
* than the computed value.
*/
public final int centerY() {
return (top + bottom) >> 1;
}
/**
* @return the exact horizontal center of the rectangle as a float.
*/
public final float exactCenterX() {
return (left + right) * 0.5f;
}
/**
* @return the exact vertical center of the rectangle as a float.
*/
public final float exactCenterY() {
return (top + bottom) * 0.5f;
}
/**
* Set the rectangle to (0,0,0,0)
*/
public void setEmpty() {
left = right = top = bottom = 0;
}
/**
* Set the rectangle's coordinates to the specified values. Note: no range
* checking is performed, so it is up to the caller to ensure that left <=
* right and top <= bottom.
*
* @param left
* The X coordinate of the left side of the rectagle
* @param top
* The Y coordinate of the top of the rectangle
* @param right
* The X coordinate of the right side of the rectagle
* @param bottom
* The Y coordinate of the bottom of the rectangle
*/
public void set(int left, int top, int right, int bottom) {
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
/**
* Copy the coordinates from src into this rectangle.
*
* @param src
* The rectangle whose coordinates are copied into this
* rectangle.
*/
public void set(Rect src) {
this.left = src.left;
this.top = src.top;
this.right = src.right;
this.bottom = src.bottom;
}
/**
* Offset the rectangle by adding dx to its left and right coordinates, and
* adding dy to its top and bottom coordinates.
*
* @param dx
* The amount to add to the rectangle's left and right
* coordinates
* @param dy
* The amount to add to the rectangle's top and bottom
* coordinates
*/
public void offset(int dx, int dy) {
left += dx;
top += dy;
right += dx;
bottom += dy;
}
/**
* Offset the rectangle to a specific (left, top) position, keeping its
* width and height the same.
*
* @param newLeft
* The new "left" coordinate for the rectangle
* @param newTop
* The new "top" coordinate for the rectangle
*/
public void offsetTo(int newLeft, int newTop) {
right += newLeft - left;
bottom += newTop - top;
left = newLeft;
top = newTop;
}
/**
* Inset the rectangle by (dx,dy). If dx is positive, then the sides are
* moved inwards, making the rectangle narrower. If dx is negative, then the
* sides are moved outwards, making the rectangle wider. The same holds true
* for dy and the top and bottom.
*
* @param dx
* The amount to add(subtract) from the rectangle's left(right)
* @param dy
* The amount to add(subtract) from the rectangle's top(bottom)
*/
public void inset(int dx, int dy) {
left += dx;
top += dy;
right -= dx;
bottom -= dy;
}
/**
* Returns true if (x,y) is inside the rectangle. The left and top are
* considered to be inside, while the right and bottom are not. This means
* that for a x,y to be contained: left <= x < right and top <= y < bottom.
* An empty rectangle never contains any point.
*
* @param x
* The X coordinate of the point being tested for containment
* @param y
* The Y coordinate of the point being tested for containment
* @return true iff (x,y) are contained by the rectangle, where containment
* means left <= x < right and top <= y < bottom
*/
public boolean contains(int x, int y) {
return left < right && top < bottom // check for empty first
&& x >= left && x < right && y >= top && y < bottom;
}
/**
* Returns true iff the 4 specified sides of a rectangle are inside or equal
* to this rectangle. i.e. is this rectangle a superset of the specified
* rectangle. An empty rectangle never contains another rectangle.
*
* @param left
* The left side of the rectangle being tested for containment
* @param top
* The top of the rectangle being tested for containment
* @param right
* The right side of the rectangle being tested for containment
* @param bottom
* The bottom of the rectangle being tested for containment
* @return true iff the the 4 specified sides of a rectangle are inside or
* equal to this rectangle
*/
public boolean contains(int left, int top, int right, int bottom) {
// check for empty first
return this.left < this.right && this.top < this.bottom
// now check for containment
&& this.left <= left && this.top <= top && this.right >= right
&& this.bottom >= bottom;
}
/**
* Returns true iff the specified rectangle r is inside or equal to this
* rectangle. An empty rectangle never contains another rectangle.
*
* @param r
* The rectangle being tested for containment.
* @return true iff the specified rectangle r is inside or equal to this
* rectangle
*/
public boolean contains(Rect r) {
// check for empty first
return this.left < this.right && this.top < this.bottom
// now check for containment
&& left <= r.left && top <= r.top && right >= r.right && bottom >= r.bottom;
}
/**
* If the rectangle specified by left,top,right,bottom intersects this
* rectangle, return true and set this rectangle to that intersection,
* otherwise return false and do not change this rectangle. No check is
* performed to see if either rectangle is empty. Note: To just test for
* intersection, use intersects()
*
* @param left
* The left side of the rectangle being intersected with this
* rectangle
* @param top
* The top of the rectangle being intersected with this rectangle
* @param right
* The right side of the rectangle being intersected with this
* rectangle.
* @param bottom
* The bottom of the rectangle being intersected with this
* rectangle.
* @return true if the specified rectangle and this rectangle intersect (and
* this rectangle is then set to that intersection) else return
* false and do not change this rectangle.
*/
public boolean intersect(int left, int top, int right, int bottom) {
if (this.left < right && left < this.right && this.top < bottom && top < this.bottom) {
if (this.left < left) {
this.left = left;
}
if (this.top < top) {
this.top = top;
}
if (this.right > right) {
this.right = right;
}
if (this.bottom > bottom) {
this.bottom = bottom;
}
return true;
}
return false;
}
/**
* If the specified rectangle intersects this rectangle, return true and set
* this rectangle to that intersection, otherwise return false and do not
* change this rectangle. No check is performed to see if either rectangle
* is empty. To just test for intersection, use intersects()
*
* @param r
* The rectangle being intersected with this rectangle.
* @return true if the specified rectangle and this rectangle intersect (and
* this rectangle is then set to that intersection) else return
* false and do not change this rectangle.
*/
public boolean intersect(Rect r) {
return intersect(r.left, r.top, r.right, r.bottom);
}
/**
* If rectangles a and b intersect, return true and set this rectangle to
* that intersection, otherwise return false and do not change this
* rectangle. No check is performed to see if either rectangle is empty. To
* just test for intersection, use intersects()
*
* @param a
* The first rectangle being intersected with
* @param b
* The second rectangle being intersected with
* @return true iff the two specified rectangles intersect. If they do, set
* this rectangle to that intersection. If they do not, return false
* and do not change this rectangle.
*/
public boolean setIntersect(Rect a, Rect b) {
if (a.left < b.right && b.left < a.right && a.top < b.bottom && b.top < a.bottom) {
left = Math.max(a.left, b.left);
top = Math.max(a.top, b.top);
right = Math.min(a.right, b.right);
bottom = Math.min(a.bottom, b.bottom);
return true;
}
return false;
}
/**
* Returns true if this rectangle intersects the specified rectangle. In no
* event is this rectangle modified. No check is performed to see if either
* rectangle is empty. To record the intersection, use intersect() or
* setIntersect().
*
* @param left
* The left side of the rectangle being tested for intersection
* @param top
* The top of the rectangle being tested for intersection
* @param right
* The right side of the rectangle being tested for intersection
* @param bottom
* The bottom of the rectangle being tested for intersection
* @return true iff the specified rectangle intersects this rectangle. In no
* event is this rectangle modified.
*/
public boolean intersects(int left, int top, int right, int bottom) {
return this.left < right && left < this.right && this.top < bottom && top < this.bottom;
}
/**
* Returns true iff the two specified rectangles intersect. In no event are
* either of the rectangles modified. To record the intersection, use
* intersect() or setIntersect().
*
* @param a
* The first rectangle being tested for intersection
* @param b
* The second rectangle being tested for intersection
* @return true iff the two specified rectangles intersect. In no event are
* either of the rectangles modified.
*/
public static boolean intersects(Rect a, Rect b) {
return a.left < b.right && b.left < a.right && a.top < b.bottom && b.top < a.bottom;
}
/**
* Update this Rect to enclose itself and the specified rectangle. If the
* specified rectangle is empty, nothing is done. If this rectangle is empty
* it is set to the specified rectangle.
*
* @param left
* The left edge being unioned with this rectangle
* @param top
* The top edge being unioned with this rectangle
* @param right
* The right edge being unioned with this rectangle
* @param bottom
* The bottom edge being unioned with this rectangle
*/
public void union(int left, int top, int right, int bottom) {
if ((left < right) && (top < bottom)) {
if ((this.left < this.right) && (this.top < this.bottom)) {
if (this.left > left)
this.left = left;
if (this.top > top)
this.top = top;
if (this.right < right)
this.right = right;
if (this.bottom < bottom)
this.bottom = bottom;
} else {
this.left = left;
this.top = top;
this.right = right;
this.bottom = bottom;
}
}
}
/**
* Update this Rect to enclose itself and the specified rectangle. If the
* specified rectangle is empty, nothing is done. If this rectangle is empty
* it is set to the specified rectangle.
*
* @param r
* The rectangle being unioned with this rectangle
*/
public void union(Rect r) {
union(r.left, r.top, r.right, r.bottom);
}
/**
* Update this Rect to enclose itself and the [x,y] coordinate. There is no
* check to see that this rectangle is non-empty.
*
* @param x
* The x coordinate of the point to add to the rectangle
* @param y
* The y coordinate of the point to add to the rectangle
*/
public void union(int x, int y) {
if (x < left) {
left = x;
} else if (x > right) {
right = x;
}
if (y < top) {
top = y;
} else if (y > bottom) {
bottom = y;
}
}
/**
* Swap top/bottom or left/right if there are flipped (i.e. left > right
* and/or top > bottom). This can be called if the edges are computed
* separately, and may have crossed over each other. If the edges are
* already correct (i.e. left <= right and top <= bottom) then nothing is
* done.
*/
public void sort() {
if (left > right) {
int temp = left;
left = right;
right = temp;
}
if (top > bottom) {
int temp = top;
top = bottom;
bottom = temp;
}
}
/**
* Scales up the rect by the given scale.
*
* @hide
*/
public void scale(float scale) {
if (scale != 1.0f) {
left = (int) (left * scale + 0.5f);
top = (int) (top * scale + 0.5f);
right = (int) (right * scale + 0.5f);
bottom = (int) (bottom * scale + 0.5f);
}
}
}