131 lines
4.2 KiB
Java
131 lines
4.2 KiB
Java
/*
|
|
* Copyright 2019 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 org.thoughtcrime.securesms.mediasend.camerax;
|
|
|
|
import android.content.Context;
|
|
import android.graphics.Matrix;
|
|
import android.graphics.RectF;
|
|
import android.util.AttributeSet;
|
|
import android.view.SurfaceView;
|
|
|
|
import androidx.annotation.NonNull;
|
|
import androidx.annotation.Nullable;
|
|
import androidx.annotation.RequiresApi;
|
|
|
|
/**
|
|
* A subclass of {@link SurfaceView} that supports translation and scaling transformations.
|
|
*/
|
|
// Begin Signal Custom Code Block
|
|
@RequiresApi(21)
|
|
// End Signal Custom Code Block
|
|
final class TransformableSurfaceView extends SurfaceView {
|
|
|
|
private RectF mOverriddenLayoutRect;
|
|
|
|
TransformableSurfaceView(@NonNull Context context) {
|
|
super(context);
|
|
}
|
|
|
|
TransformableSurfaceView(@NonNull Context context, @Nullable AttributeSet attrs) {
|
|
super(context, attrs);
|
|
}
|
|
|
|
TransformableSurfaceView(@NonNull Context context, @Nullable AttributeSet attrs,
|
|
int defStyleAttr) {
|
|
super(context, attrs, defStyleAttr);
|
|
}
|
|
|
|
TransformableSurfaceView(@NonNull Context context, @Nullable AttributeSet attrs,
|
|
int defStyleAttr, int defStyleRes) {
|
|
super(context, attrs, defStyleAttr, defStyleRes);
|
|
}
|
|
|
|
@Override
|
|
protected void onMeasure(int widthMeasureSpec, int heightMeasureSpec) {
|
|
if (mOverriddenLayoutRect == null) {
|
|
super.onMeasure(widthMeasureSpec, heightMeasureSpec);
|
|
} else {
|
|
setMeasuredDimension((int) mOverriddenLayoutRect.width(),
|
|
(int) mOverriddenLayoutRect.height());
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Sets the transform to associate with this surface view. Only translation and scaling are
|
|
* supported. If a rotated transformation is passed in, an exception is thrown.
|
|
*
|
|
* @param transform The transform to apply to the content of this view.
|
|
*/
|
|
void setTransform(final Matrix transform) {
|
|
if (hasRotation(transform)) {
|
|
throw new IllegalArgumentException("TransformableSurfaceView does not support "
|
|
+ "rotation transformations.");
|
|
}
|
|
|
|
final RectF rect = new RectF(getLeft(), getTop(), getRight(), getBottom());
|
|
transform.mapRect(rect);
|
|
overrideLayout(rect);
|
|
}
|
|
|
|
private boolean hasRotation(final Matrix matrix) {
|
|
final float[] values = new float[9];
|
|
matrix.getValues(values);
|
|
|
|
/*
|
|
A translation matrix can be represented as:
|
|
(1 0 transX)
|
|
(0 1 transX)
|
|
(0 0 1)
|
|
|
|
A rotation Matrix of ψ degrees can be represented as:
|
|
(cosψ -sinψ 0)
|
|
(sinψ cosψ 0)
|
|
(0 0 1)
|
|
|
|
A scale matrix can be represented as:
|
|
(scaleX 0 0)
|
|
(0 scaleY 0)
|
|
(0 0 0)
|
|
|
|
Meaning a transformed matrix can be represented as:
|
|
(scaleX * cosψ -scaleX * sinψ transX)
|
|
(scaleY * sinψ scaleY * cosψ transY)
|
|
(0 0 1)
|
|
|
|
Using the following 2 equalities:
|
|
scaleX * cosψ = matrix[0][0]
|
|
-scaleX * sinψ = matrix[0][1]
|
|
|
|
The following is deduced:
|
|
-tanψ = matrix[0][1] / matrix[0][0]
|
|
|
|
Or:
|
|
ψ = -arctan(matrix[0][1] / matrix[0][0])
|
|
*/
|
|
final double angle = -Math.atan2(values[Matrix.MSKEW_X], values[Matrix.MSCALE_X]);
|
|
|
|
return Math.round(angle * (180 / Math.PI)) != 0;
|
|
}
|
|
|
|
private void overrideLayout(final RectF overriddenLayoutRect) {
|
|
mOverriddenLayoutRect = overriddenLayoutRect;
|
|
setX(overriddenLayoutRect.left);
|
|
setY(overriddenLayoutRect.top);
|
|
requestLayout();
|
|
}
|
|
}
|