/*
* Copyright (c) 2005, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code 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. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code 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 in the LICENSE file that
* accompanied this code).
*
* 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 Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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*/
package sun.java2d.pipe;
import java.awt.AlphaComposite;
import java.awt.Composite;
import java.awt.Paint;
import java.awt.geom.AffineTransform;
import sun.java2d.InvalidPipeException;
import sun.java2d.SunGraphics2D;
import sun.java2d.SurfaceData;
import sun.java2d.loops.XORComposite;
import static sun.java2d.pipe.BufferedOpCodes.*;
import static sun.java2d.pipe.BufferedRenderPipe.BYTES_PER_SPAN;
/**
* Base context class for managing state in a single-threaded rendering
* environment. Each state-setting operation (e.g. SET_COLOR) is added to
* the provided RenderQueue, which will be processed at a later time by a
* single thread. Note that the RenderQueue lock must be acquired before
* calling the validate() method (or any other method in this class). See
* the RenderQueue class comments for a sample usage scenario.
*/
public class BufferedContext {
/*
* The following flags help the internals of validate() determine
* the appropriate (meaning correct, or optimal) code path when
* setting up the current context. The flags can be bitwise OR'd
* together as needed.
*/
/**
* Indicates that no flags are needed; take all default code paths.
*/
public static final int NO_CONTEXT_FLAGS = (0 << 0);
/**
* Indicates that the source surface (or color value, if it is a simple
* rendering operation) is opaque (has an alpha value of 1.0). If this
* flag is present, it allows us to disable blending in certain
* situations in order to improve performance.
*/
public static final int SRC_IS_OPAQUE = (1 << 0);
/**
* Indicates that the operation uses an alpha mask, which may determine
* the code path that is used when setting up the current paint state.
*/
public static final int USE_MASK = (1 << 1);
protected RenderQueue rq;
protected RenderBuffer buf;
/**
* This is a reference to the most recently validated BufferedContext. If
* this value is null, it means that there is no current context. It is
* provided here so that validate() only needs to do a quick reference
* check to see if the BufferedContext passed to that method is the same
* as the one we've cached here.
*/
protected static BufferedContext currentContext;
private SurfaceData validatedSrcData;
private SurfaceData validatedDstData;
private Region validatedClip;
private Composite validatedComp;
private Paint validatedPaint;
private int validatedFlags;
private boolean xformInUse;
protected BufferedContext(RenderQueue rq) {
this.rq = rq;
this.buf = rq.getBuffer();
}
/**
* Validates the given parameters against the current state for this
* context. If this context is not current, it will be made current
* for the given source and destination surfaces, and the viewport will
* be updated. Then each part of the context state (clip, composite,
* etc.) is checked against the previous value. If the value has changed
* since the last call to validate(), it will be updated accordingly.
*
* Note that the SunGraphics2D parameter is only used for the purposes
* of validating a (non-null) Paint parameter. In all other cases it
* is safe to pass a null SunGraphics2D and it will be ignored.
*/
public void validate(SurfaceData srcData, SurfaceData dstData,
Region clip, Composite comp,
AffineTransform xform,
Paint paint, SunGraphics2D sg2d, int flags)
{
// assert rq.lock.isHeldByCurrentThread();
boolean updateClip = (clip != validatedClip);
boolean updatePaint = (paint != validatedPaint);
if (!dstData.isValid()) {
throw new InvalidPipeException("bounds changed");
}
if ((currentContext != this) ||
(srcData != validatedSrcData) ||
(dstData != validatedDstData))
{
if (dstData != validatedDstData) {
// the clip is dependent on the destination surface, so we
// need to update it if we have a new destination surface
updateClip = true;
}
if (paint == null) {
// make sure we update the color state (otherwise, it might
// not be updated if this is the first time the context
// is being validated)
updatePaint = true;
}
// update the current source and destination surfaces
setSurfaces(srcData, dstData);
currentContext = this;
validatedSrcData = srcData;
validatedDstData = dstData;
}
// validate clip
if (updateClip) {
if (clip != null) {
setClip(clip);
} else {
resetClip();
}
validatedClip = clip;
}
// validate composite (note that a change in the context flags
// may require us to update the composite state, even if the
// composite has not changed)
if ((comp != validatedComp) || (flags != validatedFlags)) {
if (comp != null) {
setComposite(comp, flags);
} else {
resetComposite();
}
// the paint state is dependent on the composite state, so make
// sure we update the color below
updatePaint = true;
validatedComp = comp;
validatedFlags = flags;
}
// validate transform
if (xform == null) {
if (xformInUse) {
resetTransform();
xformInUse = false;
}
} else {
setTransform(xform);
xformInUse = true;
}
// validate paint
if (updatePaint) {
if (paint != null) {
BufferedPaints.setPaint(rq, sg2d, paint, flags);
} else {
BufferedPaints.resetPaint(rq);
}
validatedPaint = paint;
}
// mark dstData dirty
dstData.markDirty();
}
/**
* Invalidates the surfaces associated with this context. This is
* useful when the context is no longer needed, and we want to break
* the chain caused by these surface references.
*/
public void invalidateSurfaces() {
validatedSrcData = null;
validatedDstData = null;
}
private void setSurfaces(SurfaceData srcData, SurfaceData dstData) {
// assert rq.lock.isHeldByCurrentThread();
rq.ensureCapacityAndAlignment(20, 4);
buf.putInt(SET_SURFACES);
buf.putLong(srcData.getNativeOps());
buf.putLong(dstData.getNativeOps());
}
private void resetClip() {
// assert rq.lock.isHeldByCurrentThread();
rq.ensureCapacity(4);
buf.putInt(RESET_CLIP);
}
private void setClip(Region clip) {
// assert rq.lock.isHeldByCurrentThread();
if (clip.isRectangular()) {
rq.ensureCapacity(20);
buf.putInt(SET_RECT_CLIP);
buf.putInt(clip.getLoX()).putInt(clip.getLoY());
buf.putInt(clip.getHiX()).putInt(clip.getHiY());
} else {
rq.ensureCapacity(28); // so that we have room for at least a span
buf.putInt(BEGIN_SHAPE_CLIP);
buf.putInt(SET_SHAPE_CLIP_SPANS);
// include a placeholder for the span count
int countIndex = buf.position();
buf.putInt(0);
int spanCount = 0;
int remainingSpans = buf.remaining() / BYTES_PER_SPAN;
int span[] = new int[4];
SpanIterator si = clip.getSpanIterator();
while (si.nextSpan(span)) {
if (remainingSpans == 0) {
buf.putInt(countIndex, spanCount);
rq.flushNow();
buf.putInt(SET_SHAPE_CLIP_SPANS);
countIndex = buf.position();
buf.putInt(0);
spanCount = 0;
remainingSpans = buf.remaining() / BYTES_PER_SPAN;
}
buf.putInt(span[0]); // x1
buf.putInt(span[1]); // y1
buf.putInt(span[2]); // x2
buf.putInt(span[3]); // y2
spanCount++;
remainingSpans--;
}
buf.putInt(countIndex, spanCount);
rq.ensureCapacity(4);
buf.putInt(END_SHAPE_CLIP);
}
}
private void resetComposite() {
// assert rq.lock.isHeldByCurrentThread();
rq.ensureCapacity(4);
buf.putInt(RESET_COMPOSITE);
}
private void setComposite(Composite comp, int flags) {
// assert rq.lock.isHeldByCurrentThread();
if (comp instanceof AlphaComposite) {
AlphaComposite ac = (AlphaComposite)comp;
rq.ensureCapacity(16);
buf.putInt(SET_ALPHA_COMPOSITE);
buf.putInt(ac.getRule());
buf.putFloat(ac.getAlpha());
buf.putInt(flags);
} else if (comp instanceof XORComposite) {
int xorPixel = ((XORComposite)comp).getXorPixel();
rq.ensureCapacity(8);
buf.putInt(SET_XOR_COMPOSITE);
buf.putInt(xorPixel);
} else {
throw new InternalError("not yet implemented");
}
}
private void resetTransform() {
// assert rq.lock.isHeldByCurrentThread();
rq.ensureCapacity(4);
buf.putInt(RESET_TRANSFORM);
}
private void setTransform(AffineTransform xform) {
// assert rq.lock.isHeldByCurrentThread();
rq.ensureCapacityAndAlignment(52, 4);
buf.putInt(SET_TRANSFORM);
buf.putDouble(xform.getScaleX());
buf.putDouble(xform.getShearY());
buf.putDouble(xform.getShearX());
buf.putDouble(xform.getScaleY());
buf.putDouble(xform.getTranslateX());
buf.putDouble(xform.getTranslateY());
}
}