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package com.sun.scenario.effect;

import com.sun.javafx.geom.Point2D;
import com.sun.javafx.geom.Rectangle;
import com.sun.javafx.geom.transform.BaseTransform;
import com.sun.scenario.effect.impl.state.RenderState;

An effect that merges two inputs together into one result. This produces the same result as using the Blend effect with Blend.Mode.SRC_OVER and opacity=1.0, except possibly more efficient. /**
 * An effect that merges two inputs together into one result.  This produces
 * the same result as using the {@code Blend} effect with
 * {@code Blend.Mode.SRC_OVER} and {@code opacity=1.0}, except possibly
 * more efficient.
 */
public class Merge extends CoreEffect<RenderState> {

    
Constructs a new Merge effect for the given inputs. 
Params:
bottomInput – the bottom input
topInput – the top input/**
     * Constructs a new {@code Merge} effect for the given inputs.
     *
     * @param bottomInput the bottom input
     * @param topInput the top input
     */
    public Merge(Effect bottomInput, Effect topInput) {
        super(bottomInput, topInput);
        updatePeerKey("Merge");
    }

    
Returns the bottom input for this Effect. 
Returns:
the bottom input for this Effect/**
     * Returns the bottom input for this {@code Effect}.
     *
     * @return the bottom input for this {@code Effect}
     */
    public final Effect getBottomInput() {
        return getInputs().get(0);
    }

    
Sets the bottom input for this Effect to a specific Effect or to the default input if input is null. 
Params:
bottomInput – the bottom input for this Effect/**
     * Sets the bottom input for this {@code Effect} to a specific
     * {@code Effect} or to the default input if {@code input} is
     * {@code null}.
     *
     * @param bottomInput the bottom input for this {@code Effect}
     */
    public void setBottomInput(Effect bottomInput) {
        setInput(0, bottomInput);
    }

    
Returns the top input for this Effect. 
Returns:
the top input for this Effect/**
     * Returns the top input for this {@code Effect}.
     *
     * @return the top input for this {@code Effect}
     */
    public final Effect getTopInput() {
        return getInputs().get(1);
    }

    
Sets the top input for this Effect to a specific Effect or to the default input if input is null. 
Params:
topInput – the top input for this Effect/**
     * Sets the top input for this {@code Effect} to a specific
     * {@code Effect} or to the default input if {@code input} is
     * {@code null}.
     *
     * @param topInput the top input for this {@code Effect}
     */
    public void setTopInput(Effect topInput) {
        setInput(1, topInput);
    }

    
Transform the specified point p from the coordinate space of the primary content input to the coordinate space of the effect output. In essence, this method asks the question "Which output coordinate is most affected by the data at the specified coordinate in the primary source input?" 
 The Merge effect delegates this operation to its top input, or the defaultInput if the top input is null. 
Params:
p – the point in the coordinate space of the primary content
         input to be transformed
defaultInput – the default input Effect to be used in all cases where a filter has a null input
Returns:
the transformed point in the coordinate space of the result/**
     * Transform the specified point {@code p} from the coordinate space
     * of the primary content input to the coordinate space of the effect
     * output.
     * In essence, this method asks the question "Which output coordinate
     * is most affected by the data at the specified coordinate in the
     * primary source input?"
     * <p>
     * The {@code Merge} effect delegates this operation to its {@code top}
     * input, or the {@code defaultInput} if the {@code top} input is
     * {@code null}.
     *
     * @param p the point in the coordinate space of the primary content
     *          input to be transformed
     * @param defaultInput the default input {@code Effect} to be used in
     *                     all cases where a filter has a null input
     * @return the transformed point in the coordinate space of the result
     */
    @Override
    public Point2D transform(Point2D p, Effect defaultInput) {
        return getDefaultedInput(1, defaultInput).transform(p, defaultInput);
    }

    
Transform the specified point p from the coordinate space of the output of the effect into the coordinate space of the primary content input. In essence, this method asks the question "Which source coordinate contributes most to the definition of the output at the specified coordinate?" 
 The Merge effect delegates this operation to its top input, or the defaultInput if the top input is null. 
Params:
p – the point in the coordinate space of the result output
         to be transformed
defaultInput – the default input Effect to be used in all cases where a filter has a null input
Returns:
the untransformed point in the coordinate space of the
        primary content input/**
     * Transform the specified point {@code p} from the coordinate space
     * of the output of the effect into the coordinate space of the
     * primary content input.
     * In essence, this method asks the question "Which source coordinate
     * contributes most to the definition of the output at the specified
     * coordinate?"
     * <p>
     * The {@code Merge} effect delegates this operation to its {@code top}
     * input, or the {@code defaultInput} if the {@code top} input is
     * {@code null}.
     *
     * @param p the point in the coordinate space of the result output
     *          to be transformed
     * @param defaultInput the default input {@code Effect} to be used in
     *                     all cases where a filter has a null input
     * @return the untransformed point in the coordinate space of the
     *         primary content input
     */
    @Override
    public Point2D untransform(Point2D p, Effect defaultInput) {
        return getDefaultedInput(1, defaultInput).untransform(p, defaultInput);
    }

    @Override
    public ImageData filter(FilterContext fctx,
                            BaseTransform transform,
                            Rectangle outputClip,
                            Object renderHelper,
                            Effect defaultInput)
    {
        Effect botinput = getDefaultedInput(0, defaultInput);
        Effect topinput = getDefaultedInput(1, defaultInput);
        ImageData botimg = botinput.filter(fctx, transform, outputClip,
                                           renderHelper, defaultInput);
        if (botimg != null) {
            if (!botimg.validate(fctx)) {
                return new ImageData(fctx, null, null);
            }
            if (renderHelper instanceof ImageDataRenderer) {
                ImageDataRenderer imgr = (ImageDataRenderer) renderHelper;
                imgr.renderImage(botimg, BaseTransform.IDENTITY_TRANSFORM, fctx);
                botimg.unref();
                botimg = null;
            }
        }
        if (botimg == null) {
            return topinput.filter(fctx, transform, outputClip,
                                   renderHelper, defaultInput);
        }
        ImageData topimg = topinput.filter(fctx, transform, outputClip,
                                           null, defaultInput);
        if (!topimg.validate(fctx)) {
            return new ImageData(fctx, null, null);
        }
        RenderState rstate = getRenderState(fctx, transform, outputClip,
                                            renderHelper, defaultInput);
        ImageData ret = filterImageDatas(fctx, transform, outputClip, rstate,
                                         botimg, topimg);
        botimg.unref();
        topimg.unref();
        return ret;
    }

    @Override
    public RenderState getRenderState(FilterContext fctx,
                                      BaseTransform transform,
                                      Rectangle outputClip,
                                      Object renderHelper,
                                      Effect defaultInput)
    {
        return RenderState.RenderSpaceRenderState;
    }

    @Override
    public boolean reducesOpaquePixels() {
        final Effect topInput = getTopInput();
        final Effect bottomInput = getBottomInput();
        return topInput != null && topInput.reducesOpaquePixels() && bottomInput != null && bottomInput.reducesOpaquePixels();
    }

}