/*
* $RCSfile: Viewport.java,v $
*
* Copyright 1990-2009 Sun Microsystems, Inc. All Rights Reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of the GNU General Public License version
* 2 only, as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful, but
* WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License version 2 for more details (a copy is
* included at /legal/license.txt).
*
* You should have received a copy of the GNU General Public License
* version 2 along with this work; if not, write to the Free Software
* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA
*
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa
* Clara, CA 95054 or visit www.sun.com if you need additional
* information or have any questions.
*/
package com.sun.perseus.model;
import com.sun.perseus.j2d.Transform;
/**
* A <code>Viewport</code> describes a <code>ModelNode</code> into which
* rendering may happen.
*
* <p>A <code>ViewportNode</code> has a width and height
* which a child <code>SVG</code> uses to compute the viewbox to viewport
* transform.</p>
*
* <p>In addition, a <code>Viewport</code> has a user transform limited to
* its scale and translation components.</p>
*
* <p>The <code>Viewport</code> is the root of any SVG fragment hierarchy.
* </p>
*
* @version $Id: Viewport.java,v 1.9 2006/06/29 10:47:36 ln156897 Exp $
*/
public abstract class Viewport extends CompositeNode implements Transformable {
/**
* Default width for viewports.
*/
public static final int DEFAULT_VIEWPORT_WIDTH = 100;
/**
* Default height for viewports
*/
public static final int DEFAULT_VIEWPORT_HEIGHT = 100;
/**
* As in the SVG 1.1 specification
*/
public static final int ZOOM_PAN_MAGNIFY = 0;
/**
* As in the SVG 1.1 specification
*/
public static final int ZOOM_PAN_DISABLE = 1;
/**
* As in the SVG 1.1 specification
*/
public static final int ZOOM_PAN_UNKNOWN = 2;
/**
* Viewport width
*/
protected int width = DEFAULT_VIEWPORT_WIDTH;
/**
* Viewport height
*/
protected int height = DEFAULT_VIEWPORT_HEIGHT;
/**
* The Transform applied to this node.
*/
protected Transform transform = new Transform(null);
/**
* The inverse of the Transform applied to this node.
*/
protected Transform inverseTxf = new Transform(null);
/**
* The zoomAndPan setting
*/
protected int zoomAndPan = ZOOM_PAN_MAGNIFY;
/**
* Default constructor
*/
public Viewport() {
}
/**
* Returns the <code>ModelNode</code>, if any, hit by the
* point at coordinate x/y.
*
* @param pt the x/y coordinate. Should never be null and be
* of size two. If not, the behavior is unspecified.
* The coordinates are in viewport space.
* @return the <tt>ModelNode</tt> hit at the given point or null
* if none was hit.
*/
public ModelNode nodeHitAt(final float[] pt) {
// Check for a hit on children
return nodeHitAt(getLastChildNode(), pt);
}
/**
* @return The zoomAndPan setting for this viewport (read-only)
*/
public int getZoomAndPan() {
return zoomAndPan;
}
/**
* @param newZoomAndPan the new value for the zoom and pan setting
*/
public void setZoomAndPan(final int newZoomAndPan) {
if (newZoomAndPan != ZOOM_PAN_MAGNIFY
&&
newZoomAndPan != ZOOM_PAN_DISABLE
&&
newZoomAndPan != ZOOM_PAN_UNKNOWN) {
throw new IllegalArgumentException();
}
if (newZoomAndPan == zoomAndPan) {
return;
}
modifyingNode();
this.zoomAndPan = newZoomAndPan;
modifiedNode();
}
/////////////////////
/**
* @return the viewport width
*/
public int getWidth() {
return this.width;
}
/**
* @return the viewport height
*/
public int getHeight() {
return this.height;
}
/**
* Sets the viewport size
*
* @param newWidth the new viewport width. Should be greater than 0
* @param newHeight the new viewport height. Should be greater than 0.
*/
public void setSize(final int newWidth, final int newHeight) {
if (newWidth < 0 || newHeight < 0) {
throw new IllegalArgumentException();
}
if (newWidth == width && newHeight == height) {
return;
}
modifyingNode();
this.width = newWidth;
this.height = newHeight;
recomputeTransformState(null);
computeCanRenderWidthBit(width);
computeCanRenderHeightBit(height);
modifiedNode();
}
/**
* @return this node's cached transform.
*/
public Transform getTransformState() {
return transform;
}
/**
* @return this node's cached inverse transform.
*/
public Transform getInverseTransformState() {
if (((canRenderState & CAN_RENDER_NON_INVERTIBLE_TXF_BIT) == 0)) {
if (inverseTxf == null) {
inverseTxf = new Transform(null);
try {
inverseTxf = (Transform) transform.inverse(inverseTxf);
} catch (Exception e) {
// If we get an exception, then we have a real error
// condition, because we just checked that the
// transform was invertible.
throw new Error();
}
}
} else {
inverseTxf = null;
}
return inverseTxf;
}
/**
* Recomputes the transform cache, if one exists. This should recursively
* call recomputeTransformState on children node or expanded content, if
* any.
*
* By default, because a ModelNode has no transform and no cached transform,
* this only does a pass down.
*
* @param parentTransform the Transform applied to this node's parent.
*/
protected void recomputeTransformState(final Transform parentTransform) {
if (parentTransform != null) {
throw new IllegalArgumentException();
}
computeCanRenderTransformBit(transform);
inverseTxf = null;
recomputeTransformState(transform, getFirstChildNode());
}
/**
* @param newTransform The new <code>Transformable</code>'s transform.
*/
public void setTransform(final Transform newTransform) {
if (ElementNode.equal(newTransform, this.transform)) {
return;
}
modifyingNode();
this.transform = newTransform;
recomputeTransformState(null);
modifiedNode();
}
/**
* @return This <code>Transformable</code>'s transform.
*/
public Transform getTransform() {
return transform;
}
/**
* Appends this node's transform, if it is not null.
*
* @param tx the <code>Transform</code> to apply additional node
* transforms to. This may be null.
* @param workTx a <code>Transform</code> which can be re-used if a
* new <code>Transform</code> needs to be created and workTx
* is not the same instance as tx.
* @return a transform with this node's transform added.
*/
protected Transform appendTransform(Transform tx,
final Transform workTx) {
if (transform == null) {
return tx;
}
tx = recycleTransform(tx, workTx);
tx.mMultiply(transform);
return tx;
}
/**
* Debug helper
*
* @return a textual description of this viewport object
*/
/*
public String toString() {
return "[Viewport(zoomPan=" + zoomAndPan + ", width="
+ width + " height=" + height
+ " txf=" + transform
+ "]";
}
*/
}