tests/tests/uirendering/src/android/uirendering/cts/differencecalculators/ExactComparer.java

/*
 * Copyright (C) 2014 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.uirendering.cts.differencecalculators;

import com.android.cts.uirendering.R;
import com.android.cts.uirendering.ScriptC_ExactComparer;

import android.content.res.Resources;
import android.renderscript.Allocation;
import android.renderscript.Element;
import android.renderscript.RenderScript;
import android.uirendering.cts.CanvasCompareActivityTest;
import android.util.Log;

/**
 * This class does an exact comparison of the pixels in a bitmap.
 */
public class ExactComparer implements DifferenceCalculator {
    private final int REGION_SIZE = 8;
    private ScriptC_ExactComparer mScript;

    /**
     * This method does an exact 1 to 1 comparison of the two bitmaps
     */
    public boolean verifySame(int[] ideal, int[] given, int offset, int stride, int width,
            int height) {
        int count = 0;

        for (int i = 0 ; i < height ; i++) {
            for (int j = 0 ; j < width ; j++) {
                int index = offset + (i * stride) + j;
                if (ideal[index] != given[index]) {
                    if (!CanvasCompareActivityTest.DEBUG) {
                        return false;
                    }
                    count++;
                }
            }
        }
        if (CanvasCompareActivityTest.DEBUG) {
            Log.d("ExactComparer", "Number of different pixels : " + count);
        }

        return (count == 0);
    }

    @Override
    public boolean verifySameRS(Resources resources, Allocation ideal,
            Allocation given, int offset, int stride, int width, int height,
            RenderScript renderScript) {
        if (mScript == null) {
            mScript = new ScriptC_ExactComparer(renderScript, resources, R.raw.exactcomparer);
        }
        mScript.set_WIDTH(width);
        mScript.set_OFFSET(offset);

        //Create an array with the index of each row
        int[] inputIndices = new int[height];
        for (int i = 0; i < height; i++) {
            inputIndices[i] = i;
        }

        //Create the allocation from that given array
        Allocation inputAllocation = Allocation.createSized(renderScript, Element.I32(renderScript),
                inputIndices.length, Allocation.USAGE_SCRIPT);
        inputAllocation.copyFrom(inputIndices);

        //Create the allocation that will hold the output, the sum of pixels that differ in that
        //row
        Allocation outputAllocation = Allocation.createSized(renderScript, Element.I32(renderScript),
                inputIndices.length, Allocation.USAGE_SCRIPT);

        //Set the bitmap allocations
        mScript.set_ideal(ideal);
        mScript.set_given(given);

        //Call the renderscript function on each row
        mScript.forEach_exactCompare(inputAllocation, outputAllocation);

        //Get the values returned from the function
        int[] returnValue = new int[inputIndices.length];
        outputAllocation.copyTo(returnValue);

        int count = 0;
        //If any row had any different pixels, then it fails
        for (int i = 0; i < inputIndices.length; i++) {
            if (returnValue[i] != 0) {
                if (!CanvasCompareActivityTest.DEBUG) {
                    return false;
                } else {
                    count++;
                }
            }
        }

        Log.d("ExactComparisonRS", "Number of different pixels : " + count);

        return (count == 0);
    }
}