/*
* Copyright 2013, Edmodo, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this work except in compliance with the License.
* You may obtain a copy of the License in the LICENSE file, or 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 com.smartandroid.sa.cropper;
import android.content.Context;
import android.util.Pair;
import android.util.TypedValue;
/**
* Utility class to perform basic operations with Handles.
*/
public class HandleUtil {
// Private Constants ///////////////////////////////////////////////////////
// The radius (in dp) of the touchable area around the handle. We are basing
// this value off of the recommended 48dp Rhythm. See:
// http://developer.android.com/design/style/metrics-grids.html#48dp-rhythm
private static final int TARGET_RADIUS_DP = 24;
// Public Methods //////////////////////////////////////////////////////////
/**
* Gets the default target radius (in pixels). This is the radius of the
* circular area that can be touched in order to activate the handle.
*
* @param context
* the Context
* @return the target radius (in pixels)
*/
public static float getTargetRadius(Context context) {
final float targetRadius = TypedValue.applyDimension(
TypedValue.COMPLEX_UNIT_DIP, TARGET_RADIUS_DP, context
.getResources().getDisplayMetrics());
return targetRadius;
}
/**
* Determines which, if any, of the handles are pressed given the touch
* coordinates, the bounding box, and the touch radius.
*
* @param x
* the x-coordinate of the touch point
* @param y
* the y-coordinate of the touch point
* @param left
* the x-coordinate of the left bound
* @param top
* the y-coordinate of the top bound
* @param right
* the x-coordinate of the right bound
* @param bottom
* the y-coordinate of the bottom bound
* @param targetRadius
* the target radius in pixels
* @return the Handle that was pressed; null if no Handle was pressed
*/
public static Handle getPressedHandle(float x, float y, float left,
float top, float right, float bottom, float targetRadius) {
Handle pressedHandle = null;
// Note: corner-handles take precedence, then side-handles, then center.
if (HandleUtil.isInCornerTargetZone(x, y, left, top, targetRadius)) {
pressedHandle = Handle.TOP_LEFT;
} else if (HandleUtil.isInCornerTargetZone(x, y, right, top,
targetRadius)) {
pressedHandle = Handle.TOP_RIGHT;
} else if (HandleUtil.isInCornerTargetZone(x, y, left, bottom,
targetRadius)) {
pressedHandle = Handle.BOTTOM_LEFT;
} else if (HandleUtil.isInCornerTargetZone(x, y, right, bottom,
targetRadius)) {
pressedHandle = Handle.BOTTOM_RIGHT;
} else if (HandleUtil.isInCenterTargetZone(x, y, left, top, right,
bottom) && focusCenter()) {
pressedHandle = Handle.CENTER;
} else if (HandleUtil.isInHorizontalTargetZone(x, y, left, right, top,
targetRadius)) {
pressedHandle = Handle.TOP;
} else if (HandleUtil.isInHorizontalTargetZone(x, y, left, right,
bottom, targetRadius)) {
pressedHandle = Handle.BOTTOM;
} else if (HandleUtil.isInVerticalTargetZone(x, y, left, top, bottom,
targetRadius)) {
pressedHandle = Handle.LEFT;
} else if (HandleUtil.isInVerticalTargetZone(x, y, right, top, bottom,
targetRadius)) {
pressedHandle = Handle.RIGHT;
} else if (HandleUtil.isInCenterTargetZone(x, y, left, top, right,
bottom) && !focusCenter()) {
pressedHandle = Handle.CENTER;
}
return pressedHandle;
}
/**
* Calculates the offset of the touch point from the precise location of the
* specified handle.
*
* @return the offset as a Pair where the x-offset is the first value and
* the y-offset is the second value; null if the handle is null
*/
public static Pair<Float, Float> getOffset(Handle handle, float x, float y,
float left, float top, float right, float bottom) {
if (handle == null) {
return null;
}
float touchOffsetX = 0;
float touchOffsetY = 0;
// Calculate the offset from the appropriate handle.
switch (handle) {
case TOP_LEFT:
touchOffsetX = left - x;
touchOffsetY = top - y;
break;
case TOP_RIGHT:
touchOffsetX = right - x;
touchOffsetY = top - y;
break;
case BOTTOM_LEFT:
touchOffsetX = left - x;
touchOffsetY = bottom - y;
break;
case BOTTOM_RIGHT:
touchOffsetX = right - x;
touchOffsetY = bottom - y;
break;
case LEFT:
touchOffsetX = left - x;
touchOffsetY = 0;
break;
case TOP:
touchOffsetX = 0;
touchOffsetY = top - y;
break;
case RIGHT:
touchOffsetX = right - x;
touchOffsetY = 0;
break;
case BOTTOM:
touchOffsetX = 0;
touchOffsetY = bottom - y;
break;
case CENTER:
final float centerX = (right + left) / 2;
final float centerY = (top + bottom) / 2;
touchOffsetX = centerX - x;
touchOffsetY = centerY - y;
break;
}
final Pair<Float, Float> result = new Pair<Float, Float>(touchOffsetX,
touchOffsetY);
return result;
}
// Private Methods /////////////////////////////////////////////////////////
/**
* Determines if the specified coordinate is in the target touch zone for a
* corner handle.
*
* @param x
* the x-coordinate of the touch point
* @param y
* the y-coordinate of the touch point
* @param handleX
* the x-coordinate of the corner handle
* @param handleY
* the y-coordinate of the corner handle
* @param targetRadius
* the target radius in pixels
* @return true if the touch point is in the target touch zone; false
* otherwise
*/
private static boolean isInCornerTargetZone(float x, float y,
float handleX, float handleY, float targetRadius) {
if (Math.abs(x - handleX) <= targetRadius
&& Math.abs(y - handleY) <= targetRadius) {
return true;
}
return false;
}
/**
* Determines if the specified coordinate is in the target touch zone for a
* horizontal bar handle.
*
* @param x
* the x-coordinate of the touch point
* @param y
* the y-coordinate of the touch point
* @param handleXStart
* the left x-coordinate of the horizontal bar handle
* @param handleXEnd
* the right x-coordinate of the horizontal bar handle
* @param handleY
* the y-coordinate of the horizontal bar handle
* @param targetRadius
* the target radius in pixels
* @return true if the touch point is in the target touch zone; false
* otherwise
*/
private static boolean isInHorizontalTargetZone(float x, float y,
float handleXStart, float handleXEnd, float handleY,
float targetRadius) {
if (x > handleXStart && x < handleXEnd
&& Math.abs(y - handleY) <= targetRadius) {
return true;
}
return false;
}
/**
* Determines if the specified coordinate is in the target touch zone for a
* vertical bar handle.
*
* @param x
* the x-coordinate of the touch point
* @param y
* the y-coordinate of the touch point
* @param handleX
* the x-coordinate of the vertical bar handle
* @param handleYStart
* the top y-coordinate of the vertical bar handle
* @param handleYEnd
* the bottom y-coordinate of the vertical bar handle
* @param targetRadius
* the target radius in pixels
* @return true if the touch point is in the target touch zone; false
* otherwise
*/
private static boolean isInVerticalTargetZone(float x, float y,
float handleX, float handleYStart, float handleYEnd,
float targetRadius) {
if (Math.abs(x - handleX) <= targetRadius && y > handleYStart
&& y < handleYEnd) {
return true;
}
return false;
}
/**
* Determines if the specified coordinate falls anywhere inside the given
* bounds.
*
* @param x
* the x-coordinate of the touch point
* @param y
* the y-coordinate of the touch point
* @param left
* the x-coordinate of the left bound
* @param top
* the y-coordinate of the top bound
* @param right
* the x-coordinate of the right bound
* @param bottom
* the y-coordinate of the bottom bound
* @return true if the touch point is inside the bounding rectangle; false
* otherwise
*/
private static boolean isInCenterTargetZone(float x, float y, float left,
float top, float right, float bottom) {
if (x > left && x < right && y > top && y < bottom) {
return true;
}
return false;
}
/**
* Determines if the cropper should focus on the center handle or the side
* handles. If it is a small image, focus on the center handle so the user
* can move it. If it is a large image, focus on the side handles so user
* can grab them. Corresponds to the appearance of the
* RuleOfThirdsGuidelines.
*
* @return true if it is small enough such that it should focus on the
* center; less than show_guidelines limit
*/
private static boolean focusCenter() {
return (!CropOverlayView.showGuidelines());
}
}