blob: f92182c28b2da5569202df168dc6ce5dc0db24c5 [file] [log] [blame]
/*
* Copyright 2012 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
#include "tools/debugger/DebugCanvas.h"
#include "include/core/SkData.h"
#include "include/core/SkMatrix.h"
#include "include/core/SkPaint.h"
#include "include/core/SkPath.h"
#include "include/core/SkPicture.h"
#include "include/core/SkPoint.h"
#include "include/core/SkRSXform.h"
#include "include/core/SkShader.h"
#include "include/core/SkString.h"
#include "include/core/SkTextBlob.h"
#include "include/core/SkVertices.h"
#include "include/gpu/GrDirectContext.h"
#include "include/gpu/GrRecordingContext.h"
#include "include/private/SkTArray.h"
#include "include/utils/SkPaintFilterCanvas.h"
#include "src/core/SkCanvasPriv.h"
#include "src/core/SkRectPriv.h"
#include "src/gpu/ganesh/GrRecordingContextPriv.h"
#include "src/gpu/ganesh/GrRenderTargetProxy.h"
#include "src/gpu/ganesh/GrSurfaceProxy.h"
#include "src/utils/SkJSONWriter.h"
#include "tools/debugger/DebugLayerManager.h"
#include "tools/debugger/DrawCommand.h"
#include <string>
#include <utility>
class SkDrawable;
class SkImage;
class SkRRect;
class SkRegion;
class UrlDataManager;
struct SkDrawShadowRec;
#if SK_GPU_V1
#include "src/gpu/ganesh/GrAuditTrail.h"
#endif
#define SKDEBUGCANVAS_VERSION 1
#define SKDEBUGCANVAS_ATTRIBUTE_VERSION "version"
#define SKDEBUGCANVAS_ATTRIBUTE_COMMANDS "commands"
#define SKDEBUGCANVAS_ATTRIBUTE_AUDITTRAIL "auditTrail"
namespace {
// Constants used in Annotations by Android for keeping track of layers
static constexpr char kOffscreenLayerDraw[] = "OffscreenLayerDraw";
static constexpr char kSurfaceID[] = "SurfaceID";
static constexpr char kAndroidClip[] = "AndroidDeviceClipRestriction";
static SkPath arrowHead = SkPath::Polygon({
{ 0, 0},
{ 6, -15},
{ 0, -12},
{-6, -15},
}, true);
void drawArrow(SkCanvas* canvas, const SkPoint& a, const SkPoint& b, const SkPaint& paint) {
canvas->translate(0.5, 0.5);
canvas->drawLine(a, b, paint);
canvas->save();
canvas->translate(b.fX, b.fY);
SkScalar angle = SkScalarATan2((b.fY - a.fY), b.fX - a.fX);
canvas->rotate(angle * 180 / SK_ScalarPI - 90);
// arrow head
canvas->drawPath(arrowHead, paint);
canvas->restore();
canvas->restore();
}
} // namespace
class DebugPaintFilterCanvas : public SkPaintFilterCanvas {
public:
DebugPaintFilterCanvas(SkCanvas* canvas) : INHERITED(canvas) {}
protected:
bool onFilter(SkPaint& paint) const override {
paint.setColor(SK_ColorRED);
paint.setAlpha(0x08);
paint.setBlendMode(SkBlendMode::kSrcOver);
return true;
}
void onDrawPicture(const SkPicture* picture,
const SkMatrix* matrix,
const SkPaint* paint) override {
// We need to replay the picture onto this canvas in order to filter its internal paints.
this->SkCanvas::onDrawPicture(picture, matrix, paint);
}
private:
using INHERITED = SkPaintFilterCanvas;
};
DebugCanvas::DebugCanvas(int width, int height)
: INHERITED(width, height)
, fOverdrawViz(false)
, fClipVizColor(SK_ColorTRANSPARENT)
, fDrawGpuOpBounds(false)
, fShowAndroidClip(false)
, fShowOrigin(false)
, fnextDrawPictureLayerId(-1)
, fnextDrawImageRectLayerId(-1)
, fAndroidClip(SkRect::MakeEmpty()) {
// SkPicturePlayback uses the base-class' quickReject calls to cull clipped
// operations. This can lead to problems in the debugger which expects all
// the operations in the captured skp to appear in the debug canvas. To
// circumvent this we create a wide open clip here (an empty clip rect
// is not sufficient).
// Internally, the SkRect passed to clipRect is converted to an SkIRect and
// rounded out. The following code creates a nearly maximal rect that will
// not get collapsed by the coming conversions (Due to precision loss the
// inset has to be surprisingly large).
SkIRect largeIRect = SkRectPriv::MakeILarge();
largeIRect.inset(1024, 1024);
SkRect large = SkRect::Make(largeIRect);
#ifdef SK_DEBUG
SkASSERT(!large.roundOut().isEmpty());
#endif
// call the base class' version to avoid adding a draw command
this->INHERITED::onClipRect(large, SkClipOp::kIntersect, kHard_ClipEdgeStyle);
}
DebugCanvas::DebugCanvas(SkIRect bounds)
: DebugCanvas(bounds.width(), bounds.height()) {}
DebugCanvas::~DebugCanvas() { fCommandVector.deleteAll(); }
void DebugCanvas::addDrawCommand(DrawCommand* command) { fCommandVector.push_back(command); }
void DebugCanvas::draw(SkCanvas* canvas) {
if (!fCommandVector.empty()) {
this->drawTo(canvas, fCommandVector.size() - 1);
}
}
void DebugCanvas::drawTo(SkCanvas* originalCanvas, int index, int m) {
SkASSERT(!fCommandVector.empty());
SkASSERT(index < fCommandVector.size());
int saveCount = originalCanvas->save();
originalCanvas->resetMatrix();
SkCanvasPriv::ResetClip(originalCanvas);
DebugPaintFilterCanvas filterCanvas(originalCanvas);
SkCanvas* finalCanvas = fOverdrawViz ? &filterCanvas : originalCanvas;
#if SK_GPU_V1
auto dContext = GrAsDirectContext(finalCanvas->recordingContext());
// If we have a GPU backend we can also visualize the op information
GrAuditTrail* at = nullptr;
if (fDrawGpuOpBounds || m != -1) {
// The audit trail must be obtained from the original canvas.
at = this->getAuditTrail(originalCanvas);
}
#endif
for (int i = 0; i <= index; i++) {
#if SK_GPU_V1
GrAuditTrail::AutoCollectOps* acb = nullptr;
if (at) {
// We need to flush any pending operations, or they might combine with commands below.
// Previous operations were not registered with the audit trail when they were
// created, so if we allow them to combine, the audit trail will fail to find them.
if (dContext) {
dContext->flush();
}
acb = new GrAuditTrail::AutoCollectOps(at, i);
}
#endif
if (fCommandVector[i]->isVisible()) {
fCommandVector[i]->execute(finalCanvas);
}
#if SK_GPU_V1
if (at && acb) {
delete acb;
}
#endif
}
if (SkColorGetA(fClipVizColor) != 0) {
finalCanvas->save();
SkPaint clipPaint;
clipPaint.setColor(fClipVizColor);
finalCanvas->drawPaint(clipPaint);
finalCanvas->restore();
}
fMatrix = finalCanvas->getLocalToDevice();
fClip = finalCanvas->getDeviceClipBounds();
if (fShowOrigin) {
const SkPaint originXPaint = SkPaint({1.0, 0, 0, 1.0});
const SkPaint originYPaint = SkPaint({0, 1.0, 0, 1.0});
// Draw an origin cross at the origin before restoring to assist in visualizing the
// current matrix.
drawArrow(finalCanvas, {-50, 0}, {50, 0}, originXPaint);
drawArrow(finalCanvas, {0, -50}, {0, 50}, originYPaint);
}
finalCanvas->restoreToCount(saveCount);
if (fShowAndroidClip) {
// Draw visualization of android device clip restriction
SkPaint androidClipPaint;
androidClipPaint.setARGB(80, 255, 100, 0);
finalCanvas->drawRect(fAndroidClip, androidClipPaint);
}
#if SK_GPU_V1
// draw any ops if required and issue a full reset onto GrAuditTrail
if (at) {
// just in case there is global reordering, we flush the canvas before querying
// GrAuditTrail
GrAuditTrail::AutoEnable ae(at);
if (dContext) {
dContext->flush();
}
// we pick three colorblind-safe colors, 75% alpha
static const SkColor kTotalBounds = SkColorSetARGB(0xC0, 0x6A, 0x3D, 0x9A);
static const SkColor kCommandOpBounds = SkColorSetARGB(0xC0, 0xE3, 0x1A, 0x1C);
static const SkColor kOtherOpBounds = SkColorSetARGB(0xC0, 0xFF, 0x7F, 0x00);
// get the render target of the top device (from the original canvas) so we can ignore ops
// drawn offscreen
GrRenderTargetProxy* rtp = SkCanvasPriv::TopDeviceTargetProxy(originalCanvas);
GrSurfaceProxy::UniqueID proxyID = rtp->uniqueID();
// get the bounding boxes to draw
SkTArray<GrAuditTrail::OpInfo> childrenBounds;
if (m == -1) {
at->getBoundsByClientID(&childrenBounds, index);
} else {
// the client wants us to draw the mth op
at->getBoundsByOpsTaskID(&childrenBounds.push_back(), m);
}
// Shift the rects half a pixel, so they appear as exactly 1px thick lines.
finalCanvas->save();
finalCanvas->translate(0.5, -0.5);
SkPaint paint;
paint.setStyle(SkPaint::kStroke_Style);
paint.setStrokeWidth(1);
for (int i = 0; i < childrenBounds.count(); i++) {
if (childrenBounds[i].fProxyUniqueID != proxyID) {
// offscreen draw, ignore for now
continue;
}
paint.setColor(kTotalBounds);
finalCanvas->drawRect(childrenBounds[i].fBounds, paint);
for (int j = 0; j < childrenBounds[i].fOps.count(); j++) {
const GrAuditTrail::OpInfo::Op& op = childrenBounds[i].fOps[j];
if (op.fClientID != index) {
paint.setColor(kOtherOpBounds);
} else {
paint.setColor(kCommandOpBounds);
}
finalCanvas->drawRect(op.fBounds, paint);
}
}
finalCanvas->restore();
this->cleanupAuditTrail(at);
}
#endif
}
void DebugCanvas::deleteDrawCommandAt(int index) {
SkASSERT(index < fCommandVector.size());
delete fCommandVector[index];
fCommandVector.remove(index);
}
DrawCommand* DebugCanvas::getDrawCommandAt(int index) const {
SkASSERT(index < fCommandVector.size());
return fCommandVector[index];
}
#if SK_GPU_V1
GrAuditTrail* DebugCanvas::getAuditTrail(SkCanvas* canvas) {
GrAuditTrail* at = nullptr;
auto ctx = canvas->recordingContext();
if (ctx) {
at = ctx->priv().auditTrail();
}
return at;
}
void DebugCanvas::drawAndCollectOps(SkCanvas* canvas) {
GrAuditTrail* at = this->getAuditTrail(canvas);
if (at) {
// loop over all of the commands and draw them, this is to collect reordering
// information
for (int i = 0; i < this->getSize(); i++) {
GrAuditTrail::AutoCollectOps enable(at, i);
fCommandVector[i]->execute(canvas);
}
// in case there is some kind of global reordering
{
GrAuditTrail::AutoEnable ae(at);
auto dContext = GrAsDirectContext(canvas->recordingContext());
if (dContext) {
dContext->flush();
}
}
}
}
void DebugCanvas::cleanupAuditTrail(GrAuditTrail* at) {
if (at) {
GrAuditTrail::AutoEnable ae(at);
at->fullReset();
}
}
#endif // SK_GPU_V1
void DebugCanvas::toJSON(SkJSONWriter& writer,
UrlDataManager& urlDataManager,
SkCanvas* canvas) {
#if SK_GPU_V1
this->drawAndCollectOps(canvas);
// now collect json
GrAuditTrail* at = this->getAuditTrail(canvas);
#endif
writer.appendS32(SKDEBUGCANVAS_ATTRIBUTE_VERSION, SKDEBUGCANVAS_VERSION);
writer.beginArray(SKDEBUGCANVAS_ATTRIBUTE_COMMANDS);
for (int i = 0; i < this->getSize(); i++) {
writer.beginObject(); // command
this->getDrawCommandAt(i)->toJSON(writer, urlDataManager);
#if SK_GPU_V1
if (at) {
writer.appendName(SKDEBUGCANVAS_ATTRIBUTE_AUDITTRAIL);
at->toJson(writer, i);
}
#endif
writer.endObject(); // command
}
writer.endArray(); // commands
#if SK_GPU_V1
this->cleanupAuditTrail(at);
#endif
}
void DebugCanvas::toJSONOpsTask(SkJSONWriter& writer, SkCanvas* canvas) {
#if SK_GPU_V1
this->drawAndCollectOps(canvas);
GrAuditTrail* at = this->getAuditTrail(canvas);
if (at) {
GrAuditTrail::AutoManageOpsTask enable(at);
at->toJson(writer);
this->cleanupAuditTrail(at);
return;
}
#endif
writer.beginObject();
writer.endObject();
}
void DebugCanvas::setOverdrawViz(bool overdrawViz) { fOverdrawViz = overdrawViz; }
void DebugCanvas::onClipPath(const SkPath& path, SkClipOp op, ClipEdgeStyle edgeStyle) {
this->addDrawCommand(new ClipPathCommand(path, op, kSoft_ClipEdgeStyle == edgeStyle));
}
void DebugCanvas::onClipRect(const SkRect& rect, SkClipOp op, ClipEdgeStyle edgeStyle) {
this->addDrawCommand(new ClipRectCommand(rect, op, kSoft_ClipEdgeStyle == edgeStyle));
}
void DebugCanvas::onClipRRect(const SkRRect& rrect, SkClipOp op, ClipEdgeStyle edgeStyle) {
this->addDrawCommand(new ClipRRectCommand(rrect, op, kSoft_ClipEdgeStyle == edgeStyle));
}
void DebugCanvas::onClipRegion(const SkRegion& region, SkClipOp op) {
this->addDrawCommand(new ClipRegionCommand(region, op));
}
void DebugCanvas::onClipShader(sk_sp<SkShader> cs, SkClipOp op) {
this->addDrawCommand(new ClipShaderCommand(std::move(cs), op));
}
void DebugCanvas::onResetClip() {
this->addDrawCommand(new ResetClipCommand());
}
void DebugCanvas::didConcat44(const SkM44& m) {
this->addDrawCommand(new Concat44Command(m));
this->INHERITED::didConcat44(m);
}
void DebugCanvas::didScale(SkScalar x, SkScalar y) {
this->didConcat44(SkM44::Scale(x, y));
}
void DebugCanvas::didTranslate(SkScalar x, SkScalar y) {
this->didConcat44(SkM44::Translate(x, y));
}
void DebugCanvas::onDrawAnnotation(const SkRect& rect, const char key[], SkData* value) {
// Parse layer-releated annotations added in SkiaPipeline.cpp and RenderNodeDrawable.cpp
// the format of the annotations is <Indicator|RenderNodeId>
SkTArray<SkString> tokens;
SkStrSplit(key, "|", kStrict_SkStrSplitMode, &tokens);
if (tokens.size() == 2) {
if (tokens[0].equals(kOffscreenLayerDraw)) {
// Indicates that the next drawPicture command contains the SkPicture to render the
// node at this id in an offscreen buffer.
fnextDrawPictureLayerId = std::stoi(tokens[1].c_str());
fnextDrawPictureDirtyRect = rect.roundOut();
return; // don't record it
} else if (tokens[0].equals(kSurfaceID)) {
// Indicates that the following drawImageRect should draw the offscreen buffer.
fnextDrawImageRectLayerId = std::stoi(tokens[1].c_str());
return; // don't record it
}
}
if (strcmp(kAndroidClip, key) == 0) {
// Store this frame's android device clip restriction for visualization later.
// This annotation stands in place of the androidFramework_setDeviceClipRestriction
// which is unrecordable.
fAndroidClip = rect;
}
this->addDrawCommand(new DrawAnnotationCommand(rect, key, sk_ref_sp(value)));
}
void DebugCanvas::onDrawImage2(const SkImage* image,
SkScalar left,
SkScalar top,
const SkSamplingOptions& sampling,
const SkPaint* paint) {
this->addDrawCommand(new DrawImageCommand(image, left, top, sampling, paint));
}
void DebugCanvas::onDrawImageLattice2(const SkImage* image,
const Lattice& lattice,
const SkRect& dst,
SkFilterMode filter, // todo
const SkPaint* paint) {
this->addDrawCommand(new DrawImageLatticeCommand(image, lattice, dst, filter, paint));
}
void DebugCanvas::onDrawImageRect2(const SkImage* image,
const SkRect& src,
const SkRect& dst,
const SkSamplingOptions& sampling,
const SkPaint* paint,
SrcRectConstraint constraint) {
if (fnextDrawImageRectLayerId != -1 && fLayerManager) {
// This drawImageRect command would have drawn the offscreen buffer for a layer.
// On Android, we recorded an SkPicture of the commands that drew to the layer.
// To render the layer as it would have looked on the frame this DebugCanvas draws, we need
// to call fLayerManager->getLayerAsImage(id). This must be done just before
// drawTo(command), since it depends on the index into the layer's commands
// (managed by fLayerManager)
// Instead of adding a DrawImageRectCommand, we need a deferred command, that when
// executed, will call drawImageRect(fLayerManager->getLayerAsImage())
this->addDrawCommand(new DrawImageRectLayerCommand(
fLayerManager, fnextDrawImageRectLayerId, fFrame, src, dst, sampling,
paint, constraint));
} else {
this->addDrawCommand(new DrawImageRectCommand(image, src, dst, sampling, paint, constraint));
}
// Reset expectation so next drawImageRect is not special.
fnextDrawImageRectLayerId = -1;
}
void DebugCanvas::onDrawOval(const SkRect& oval, const SkPaint& paint) {
this->addDrawCommand(new DrawOvalCommand(oval, paint));
}
void DebugCanvas::onDrawArc(const SkRect& oval,
SkScalar startAngle,
SkScalar sweepAngle,
bool useCenter,
const SkPaint& paint) {
this->addDrawCommand(new DrawArcCommand(oval, startAngle, sweepAngle, useCenter, paint));
}
void DebugCanvas::onDrawPaint(const SkPaint& paint) {
this->addDrawCommand(new DrawPaintCommand(paint));
}
void DebugCanvas::onDrawBehind(const SkPaint& paint) {
this->addDrawCommand(new DrawBehindCommand(paint));
}
void DebugCanvas::onDrawPath(const SkPath& path, const SkPaint& paint) {
this->addDrawCommand(new DrawPathCommand(path, paint));
}
void DebugCanvas::onDrawRegion(const SkRegion& region, const SkPaint& paint) {
this->addDrawCommand(new DrawRegionCommand(region, paint));
}
void DebugCanvas::onDrawPicture(const SkPicture* picture,
const SkMatrix* matrix,
const SkPaint* paint) {
if (fnextDrawPictureLayerId != -1 && fLayerManager) {
fLayerManager->storeSkPicture(fnextDrawPictureLayerId, fFrame, sk_ref_sp(picture),
fnextDrawPictureDirtyRect);
} else {
this->addDrawCommand(new BeginDrawPictureCommand(picture, matrix, paint));
SkAutoCanvasMatrixPaint acmp(this, matrix, paint, picture->cullRect());
picture->playback(this);
this->addDrawCommand(new EndDrawPictureCommand(SkToBool(matrix) || SkToBool(paint)));
}
fnextDrawPictureLayerId = -1;
}
void DebugCanvas::onDrawPoints(PointMode mode,
size_t count,
const SkPoint pts[],
const SkPaint& paint) {
this->addDrawCommand(new DrawPointsCommand(mode, count, pts, paint));
}
void DebugCanvas::onDrawRect(const SkRect& rect, const SkPaint& paint) {
// NOTE(chudy): Messing up when renamed to DrawRect... Why?
addDrawCommand(new DrawRectCommand(rect, paint));
}
void DebugCanvas::onDrawRRect(const SkRRect& rrect, const SkPaint& paint) {
this->addDrawCommand(new DrawRRectCommand(rrect, paint));
}
void DebugCanvas::onDrawDRRect(const SkRRect& outer, const SkRRect& inner, const SkPaint& paint) {
this->addDrawCommand(new DrawDRRectCommand(outer, inner, paint));
}
void DebugCanvas::onDrawTextBlob(const SkTextBlob* blob,
SkScalar x,
SkScalar y,
const SkPaint& paint) {
this->addDrawCommand(
new DrawTextBlobCommand(sk_ref_sp(const_cast<SkTextBlob*>(blob)), x, y, paint));
}
void DebugCanvas::onDrawPatch(const SkPoint cubics[12],
const SkColor colors[4],
const SkPoint texCoords[4],
SkBlendMode bmode,
const SkPaint& paint) {
this->addDrawCommand(new DrawPatchCommand(cubics, colors, texCoords, bmode, paint));
}
void DebugCanvas::onDrawVerticesObject(const SkVertices* vertices,
SkBlendMode bmode,
const SkPaint& paint) {
this->addDrawCommand(
new DrawVerticesCommand(sk_ref_sp(const_cast<SkVertices*>(vertices)), bmode, paint));
}
void DebugCanvas::onDrawAtlas2(const SkImage* image,
const SkRSXform xform[],
const SkRect tex[],
const SkColor colors[],
int count,
SkBlendMode bmode,
const SkSamplingOptions& sampling,
const SkRect* cull,
const SkPaint* paint) {
this->addDrawCommand(
new DrawAtlasCommand(image, xform, tex, colors, count, bmode, sampling, cull, paint));
}
void DebugCanvas::onDrawShadowRec(const SkPath& path, const SkDrawShadowRec& rec) {
this->addDrawCommand(new DrawShadowCommand(path, rec));
}
void DebugCanvas::onDrawDrawable(SkDrawable* drawable, const SkMatrix* matrix) {
this->addDrawCommand(new DrawDrawableCommand(drawable, matrix));
}
void DebugCanvas::onDrawEdgeAAQuad(const SkRect& rect,
const SkPoint clip[4],
QuadAAFlags aa,
const SkColor4f& color,
SkBlendMode mode) {
this->addDrawCommand(new DrawEdgeAAQuadCommand(rect, clip, aa, color, mode));
}
void DebugCanvas::onDrawEdgeAAImageSet2(const ImageSetEntry set[],
int count,
const SkPoint dstClips[],
const SkMatrix preViewMatrices[],
const SkSamplingOptions& sampling,
const SkPaint* paint,
SrcRectConstraint constraint) {
this->addDrawCommand(new DrawEdgeAAImageSetCommand(
set, count, dstClips, preViewMatrices, sampling, paint, constraint));
}
void DebugCanvas::willRestore() {
this->addDrawCommand(new RestoreCommand());
this->INHERITED::willRestore();
}
void DebugCanvas::willSave() {
this->addDrawCommand(new SaveCommand());
this->INHERITED::willSave();
}
SkCanvas::SaveLayerStrategy DebugCanvas::getSaveLayerStrategy(const SaveLayerRec& rec) {
this->addDrawCommand(new SaveLayerCommand(rec));
(void)this->INHERITED::getSaveLayerStrategy(rec);
// No need for a full layer.
return kNoLayer_SaveLayerStrategy;
}
bool DebugCanvas::onDoSaveBehind(const SkRect* subset) {
// TODO
return false;
}
void DebugCanvas::didSetM44(const SkM44& matrix) {
this->addDrawCommand(new SetM44Command(matrix));
this->INHERITED::didSetM44(matrix);
}
void DebugCanvas::toggleCommand(int index, bool toggle) {
SkASSERT(index < fCommandVector.size());
fCommandVector[index]->setVisible(toggle);
}
std::map<int, std::vector<int>> DebugCanvas::getImageIdToCommandMap(UrlDataManager& udm) const {
// map from image ids to list of commands that reference them.
std::map<int, std::vector<int>> m;
for (int i = 0; i < this->getSize(); i++) {
const DrawCommand* command = this->getDrawCommandAt(i);
int imageIndex = -1;
// this is not an exaustive list of where images can be used, they show up in paints too.
switch (command->getOpType()) {
case DrawCommand::OpType::kDrawImage_OpType: {
imageIndex = static_cast<const DrawImageCommand*>(command)->imageId(udm);
break;
}
case DrawCommand::OpType::kDrawImageRect_OpType: {
imageIndex = static_cast<const DrawImageRectCommand*>(command)->imageId(udm);
break;
}
case DrawCommand::OpType::kDrawImageLattice_OpType: {
imageIndex = static_cast<const DrawImageLatticeCommand*>(command)->imageId(udm);
break;
}
default: break;
}
if (imageIndex >= 0) {
m[imageIndex].push_back(i);
}
}
return m;
}