自学教程：C++ CGAffineTransformMake函数代码示例

void GiCanvasIos::endPaint(bool draw){    if (m_draw->getContext())    {        if (draw && m_draw->_buffctx && m_draw->_context) {            CGContextRef context = m_draw->_context;            CGImageRef image = CGBitmapContextCreateImage(m_draw->_buffctx);            CGRect rect = CGRectMake(0, 0, m_draw->width(), m_draw->height()); // 逻辑宽高点数                        if (image) {                CGAffineTransform af = CGAffineTransformMake(1, 0, 0, -1, 0, m_draw->height());                CGContextConcatCTM(context, af);    // 图像是朝上的，上下文坐标系朝下，上下颠倒显示                                CGInterpolationQuality old = CGContextGetInterpolationQuality(context);                CGContextSetInterpolationQuality(context, kCGInterpolationNone);                CGContextDrawImage(context, rect, image);                CGContextSetInterpolationQuality(context, old);                                CGContextConcatCTM(context, CGAffineTransformInvert(af));   // 恢复成坐标系朝下                CGImageRelease(image);            }        }        if (m_draw->_buffctx) {            CGContextRelease(m_draw->_buffctx);            m_draw->_buffctx = NULL;        }        m_draw->_context = NULL;        if (owner())            owner()->_endPaint();    }}

void drawSkewedCoordinateSystem(CGContextRef context){    // alpha is 22.5 degrees and beta is 15 degrees.    float alpha = M_PI/8, beta = M_PI/12;    CGAffineTransform skew;    // Create a rectangle that is 72 units on a side    // with its origin at (0,0).    CGRect r = CGRectMake(0, 0, 72, 72);        CGContextTranslateCTM(context, 144, 144);    // Draw the coordinate axes untransformed.    drawCoordinateAxes(context);    // Fill the rectangle.    CGContextFillRect(context, r);    // Create an affine transform that skews the coordinate system,    // skewing the x-axis by alpha radians and the y-axis by beta radians.     skew = CGAffineTransformMake(1, tan(alpha), tan(beta), 1, 0, 0);    // Apply that transform to the context coordinate system.    CGContextConcatCTM(context, skew);    // Set the fill and stroke color to a dark blue.    CGContextSetRGBStrokeColor(context, 0.11, 0.208, 0.451, 1);    CGContextSetRGBFillColor(context, 0.11, 0.208, 0.451, 1);        // Draw the coordinate axes again, now transformed.    drawCoordinateAxes(context);    // Set the fill color again but with a partially transparent alpha.    CGContextSetRGBFillColor(context, 0.11, 0.208, 0.451, 0.7);    // Fill the rectangle in the transformed coordinate system.    CGContextFillRect(context, r);}

bool GiCanvasIos::drawImage(CGImageRef image, const Point2d& centerM, bool autoScale){    CGContextRef context = m_draw->getContext();    bool ret = false;        if (context && image) {        Point2d ptD = centerM * m_draw->xf().modelToDisplay();        float w = CGImageGetWidth(image);        float h = CGImageGetHeight(image);                if (autoScale) {            w *= m_draw->xf().getViewScale();            h *= m_draw->xf().getViewScale();        }                CGAffineTransform af = CGAffineTransformMake(1, 0, 0, -1, 0, m_draw->height());        af = CGAffineTransformTranslate(af, ptD.x - w * 0.5f,                                         m_draw->height() - (ptD.y + h * 0.5f));                CGContextConcatCTM(context, af);        CGContextDrawImage(context, CGRectMake(0, 0, w, h), image);        CGContextConcatCTM(context, CGAffineTransformInvert(af));        ret = true;    }        return ret;}

static inline cairo_status_t_cairo_matrix_to_unit_quartz_matrix (const cairo_matrix_t *m, CGAffineTransform *txout,				     double *xout, double *yout){    CGAffineTransform transform;    double xscale, yscale;    cairo_status_t status;    status = _cairo_matrix_compute_basis_scale_factors (m, &xscale, &yscale, 1);    if (status)	return status;    transform = CGAffineTransformMake (m->xx, - m->yx,				       - m->xy, m->yy,				       0.0f, 0.0f);    if (xout)	*xout = xscale;    if (yout)	*yout = yscale;    if (xscale)	xscale = 1.0 / xscale;    if (yscale)	yscale = 1.0 / yscale;    *txout = CGAffineTransformScale (transform, xscale, yscale);    return CAIRO_STATUS_SUCCESS;}

bool GiCanvasIos::drawCachedBitmap2(const GiCanvas* p, float x, float y, bool secondBmp){    bool ret = false;        if (p && p->getCanvasType() == getCanvasType()) {        GiCanvasIos* gs = (GiCanvasIos*)p;        int index = secondBmp ? 1 : 0;        CGImageRef image = gs->m_draw->_cacheserr[index] ? NULL : gs->m_draw->_caches[index];        CGContextRef context = m_draw->getContext();                if (context && image) {            CGRect rect = CGRectMake(x, y, m_draw->width(), m_draw->height());            CGAffineTransform af = CGAffineTransformMake(1, 0, 0, -1, 0, m_draw->height());                        CGContextConcatCTM(context, af);                        CGInterpolationQuality oldQuality = CGContextGetInterpolationQuality(context);            CGContextSetInterpolationQuality(context, kCGInterpolationNone);            CGContextDrawImage(context, rect, image);            CGContextSetInterpolationQuality(context, oldQuality);                        CGContextConcatCTM(context, CGAffineTransformInvert(af));            ret = true;        }    }        return ret;}

static void TransformHIViewToCG(CGContextRef ctx, HIViewRef theView){    // Undo the HIView coordinate flipping    HIRect bounds;    HIViewGetBounds(theView, &bounds);    CGContextConcatCTM(ctx, CGAffineTransformMake(1, 0, 0, -1, 0, bounds.size.height));}

void addOvalToPath(CGContextRef context, CGRect r){    CGAffineTransform matrix;		// Save the context's state because we are going to transform and scale it    CGContextSaveGState(context);	// Create a transform to scale the context so that a radius of 1	// is equal to the bounds of the rectangle, and transform the origin	// of the context to the center of the bounding rectangle.  The 	// center of the bounding rectangle will now be the center of	// the oval.    matrix = CGAffineTransformMake((r.size.width)/2, 0,								   0, (r.size.height)/2,								   r.origin.x + (r.size.width)/2,								   r.origin.y + (r.size.height)/2); 	// Apply the transform to the context    CGContextConcatCTM(context, matrix);	// Signal the start of a path    CGContextBeginPath(context);		// Add a circle to the path.  After the circle is transformed by the	// context's transformation matrix, it will become an oval lying	// just inside the bounding rectangle.    CGContextAddArc(context, 0, 0, 1, 0, 2*pi, true);	// Restore the context's state. This removes the translation and scaling but leaves	// the path, since the path is not part of the graphics state.	CGContextRestoreGState(context);}

void Path::translate(const FloatSize& size){    CGAffineTransform translation = CGAffineTransformMake(1, 0, 0, 1, size.width(), size.height());    CGMutablePathRef newPath = CGPathCreateMutable();    CGPathAddPath(newPath, &translation, m_path);    CGPathRelease(m_path);    m_path = newPath;}

AffineTransform::operator CGAffineTransform() const{    return CGAffineTransformMake(narrowPrecisionToCGFloat(a()),                                 narrowPrecisionToCGFloat(b()),                                 narrowPrecisionToCGFloat(c()),                                 narrowPrecisionToCGFloat(d()),                                 narrowPrecisionToCGFloat(e()),                                 narrowPrecisionToCGFloat(f()));}

CATransform3D CATransform3DSkew (CATransform3D t,CGFloat angleX, CGFloat angleY){        CGAffineTransform affineTransform  = CGAffineTransformMake(1, tanf(-angleX*M_PI/180.0f), tanf(-angleY*M_PI/180.0f), 1, 0, 0);    CATransform3D skewTransform = CATransform3DMakeAffineTransform(affineTransform);        return CATransform3DConcat(t, skewTransform);}

FX_BOOL CQuartz2D::drawGraphicsString(void*                 graphics,                                      void*                 font,                                      FX_FLOAT              fontSize,                                      FX_WORD*              glyphIndices,                                      CGPoint*           glyphPositions,                                      FX_INT32              charsCount,                                      FX_ARGB               argb,                                      CFX_AffineMatrix*     matrix ){    if (!graphics) {        return FALSE;    }    CGContextRef context = (CGContextRef) graphics;    CGContextSetFont(context, (CGFontRef)font);    CGContextSetFontSize(context, fontSize);    if (matrix) {        CGAffineTransform m = CGContextGetTextMatrix(context);        m = CGAffineTransformConcat(m,                                    CGAffineTransformMake(matrix->a,                                            matrix->b,                                            matrix->c,                                            matrix->d,                                            matrix->e,                                            matrix->f));        CGContextSetTextMatrix(context, m);    }    FX_INT32 a, r, g, b;    ArgbDecode(argb, a, r, g, b);    CGContextSetRGBFillColor(context,                             r / 255.f,                             g / 255.f,                             b / 255.f,                             a / 255.f);    CGContextSaveGState(context);#if CGFLOAT_IS_DOUBLE    CGPoint* glyphPositionsCG = new CGPoint[charsCount];    if (!glyphPositionsCG) {        return FALSE;    }    for (int index = 0; index < charsCount; ++index) {        glyphPositionsCG[index].x = glyphPositions[index].x;        glyphPositionsCG[index].y = glyphPositions[index].y;    }#else    CGPoint* glyphPositionsCG = (CGPoint*)glyphPositions;#endif    CGContextShowGlyphsAtPositions(context,                                   (CGGlyph *) glyphIndices,                                   glyphPositionsCG,                                   charsCount);#if CGFLOAT_IS_DOUBLE    delete[] glyphPositionsCG;#endif    CGContextRestoreGState(context);    return TRUE;}

TEST(AffineTransform, CGAffineTransformConstruction){    CGAffineTransform cgTransform = CGAffineTransformMake(6.0, 5.0, 4.0, 3.0, 2.0, 1.0);    WebCore::AffineTransform test(cgTransform);    testValueConstruction(test);    testGetAndSet(test);    ASSERT_FALSE(test.isIdentity());}

FX_BOOL CFX_QuartzDeviceDriver::DrawPath(const CFX_PathData*        pathData,        const CFX_AffineMatrix*       matrix,        const CFX_GraphStateData*     graphState,        FX_DWORD                      fillArgb,        FX_DWORD                      strokeArgb,        int                           fillMode,        int                           alpha_flag,        void*                         pIccTransform,        int							blend_type                                        ){    SaveState();    CGBlendMode mode = GetCGBlendMode(blend_type);    if (mode != kCGBlendModeNormal) {        CGContextSetBlendMode(_context, mode);    }    CGAffineTransform m = CGAffineTransformIdentity;    if (matrix) {        m = CGAffineTransformMake(matrix->GetA(), matrix->GetB(), matrix->GetC(), matrix->GetD(), matrix->GetE(), matrix->GetF());    }    m = CGAffineTransformConcat(m, _foxitDevice2User);    CGContextConcatCTM(_context, m);    int pathMode = 0;    if (graphState && strokeArgb) {        CGContextSetMiterLimit(_context, graphState->m_MiterLimit);        FX_FLOAT lineWidth = getLineWidth(graphState, m);        setStrokeInfo(graphState, strokeArgb, lineWidth);        pathMode |= 4;    }    if (fillMode && fillArgb) {        setFillInfo(fillArgb);        if ((fillMode & 3) == FXFILL_WINDING) {            pathMode |= 1;        } else if ((fillMode & 3) == FXFILL_ALTERNATE) {            pathMode |= 2;        }    }    setPathToContext(pathData);    if (fillMode & FXFILL_FULLCOVER) {        CGContextSetShouldAntialias(_context, false);    }    if (pathMode == 4) {        CGContextStrokePath(_context);    } else if (pathMode == 1) {        CGContextFillPath(_context);    } else if (pathMode == 2) {        CGContextEOFillPath(_context);    } else if (pathMode == 5) {        CGContextDrawPath(_context, kCGPathFillStroke);    } else if (pathMode == 6) {        CGContextDrawPath(_context, kCGPathEOFillStroke);    }    RestoreState(FALSE);    return TRUE;}

static cairo_int_status_t_cairo_quartz_init_glyph_path (cairo_quartz_scaled_font_t *font,			       cairo_scaled_glyph_t *scaled_glyph){    cairo_quartz_font_face_t *font_face = _cairo_quartz_scaled_to_face(font);    CGGlyph glyph = _cairo_quartz_scaled_glyph_index (scaled_glyph);    CGAffineTransform textMatrix;    CGPathRef glyphPath;    cairo_path_fixed_t *path;    if (glyph == INVALID_GLYPH) {	_cairo_scaled_glyph_set_path (scaled_glyph, &font->base, _cairo_path_fixed_create());	return CAIRO_STATUS_SUCCESS;    }    textMatrix = CGAffineTransformMake (font->base.scale.xx,					-font->base.scale.yx,					-font->base.scale.xy,					font->base.scale.yy,					font->base.scale.x0,					font->base.scale.y0);    textMatrix = CGAffineTransformConcat (textMatrix, CGAffineTransformMake (1.0, 0.0, 0.0, -1.0, 0.0, 0.0));    glyphPath = CGFontGetGlyphPathPtr (font_face->cgFont, &textMatrix, 0, glyph);    if (!glyphPath)	return CAIRO_INT_STATUS_UNSUPPORTED;    path = _cairo_path_fixed_create ();    if (!path) {	CGPathRelease (glyphPath);	return _cairo_error(CAIRO_STATUS_NO_MEMORY);    }    CGPathApply (glyphPath, path, _cairo_quartz_path_apply_func);    CGPathRelease (glyphPath);    _cairo_scaled_glyph_set_path (scaled_glyph, &font->base, path);    return CAIRO_STATUS_SUCCESS;}

JNIEXPORT void JNICALL OS_NATIVE(CGAffineTransformMake)	(JNIEnv *env, jclass that, jfloat arg0, jfloat arg1, jfloat arg2, jfloat arg3, jfloat arg4, jfloat arg5, jfloatArray arg6){	jfloat *lparg6=NULL;	OS_NATIVE_ENTER(env, that, CGAffineTransformMake_FUNC);	if (arg6) if ((lparg6 = (*env)->GetFloatArrayElements(env, arg6, NULL)) == NULL) goto fail;	*(CGAffineTransform *)lparg6 = CGAffineTransformMake(arg0, arg1, arg2, arg3, arg4, arg5);fail:	if (arg6 && lparg6) (*env)->ReleaseFloatArrayElements(env, arg6, lparg6, 0);	OS_NATIVE_EXIT(env, that, CGAffineTransformMake_FUNC);}

//-----------------------------------------------------------------------------void CGDrawContext::init (){	CGContextSaveGState (cgContext);	CGContextSetShouldAntialias (cgContext, false);	CGContextSetFillColorSpace (cgContext, GetCGColorSpace ());	CGContextSetStrokeColorSpace (cgContext, GetCGColorSpace ()); 	CGContextSaveGState (cgContext);	CGAffineTransform cgCTM = CGAffineTransformMake (1.0, 0.0, 0.0, -1.0, 0.0, 0.0);	CGContextSetTextMatrix (cgContext, cgCTM);	CDrawContext::init ();}

void Font::drawGlyphs(GraphicsContext* graphicsContext, const FontData* font, const GlyphBuffer& glyphBuffer,                       int from, int numGlyphs, const FloatPoint& point) const{    CGContextRef cgContext = graphicsContext->platformContext();    uint32_t oldFontSmoothingStyle = wkSetFontSmoothingStyle(cgContext);    const FontPlatformData& platformData = font->platformData();    //NSFont* drawFont;    //if ([gContext isDrawingToScreen]) {    //    drawFont = [platformData.font screenFont];    //    if (drawFont != platformData.font)    //        // We are getting this in too many places (3406411); use ERROR so it only prints on debug versions for now. (We should debug this also, eventually).    //        LOG_ERROR("Attempting to set non-screen font (%@) when drawing to screen.  Using screen font anyway, may result in incorrect metrics.",    //            [[[platformData.font fontDescriptor] fontAttributes] objectForKey:NSFontNameAttribute]);    //} else {    //    drawFont = [platformData.font printerFont];    //    if (drawFont != platformData.font)    //        NSLog(@"Attempting to set non-printer font (%@) when printing.  Using printer font anyway, may result in incorrect metrics.",    //            [[[platformData.font fontDescriptor] fontAttributes] objectForKey:NSFontNameAttribute]);    //}    CGContextSetFont(cgContext, platformData.cgFont());    CGAffineTransform matrix = CGAffineTransformIdentity;    matrix.b = -matrix.b;    matrix.d = -matrix.d;    if (platformData.syntheticOblique())    {        static float skew = -tanf(syntheticObliqueAngle * acosf(0) / 90);        matrix = CGAffineTransformConcat(matrix, CGAffineTransformMake(1, 0, skew, 1, 0, 0));    }    // Uniscribe gives us offsets to help refine the positioning of combining glyphs.    FloatSize translation = glyphBuffer.offsetAt(from);    if (translation.width() || translation.height())        CGAffineTransformTranslate(matrix, translation.width(), translation.height());        CGContextSetTextMatrix(cgContext, matrix);    //wkSetCGFontRenderingMode(cgContext, drawFont);    CGContextSetFontSize(cgContext, platformData.size());    CGContextSetTextPosition(cgContext, point.x(), point.y());    CGContextShowGlyphsWithAdvances(cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);    if (font->m_syntheticBoldOffset) {        CGContextSetTextPosition(cgContext, point.x() + font->m_syntheticBoldOffset, point.y());        CGContextShowGlyphsWithAdvances(cgContext, glyphBuffer.glyphs(from), glyphBuffer.advances(from), numGlyphs);    }    wkRestoreFontSmoothingStyle(cgContext, oldFontSmoothingStyle);}

static CGAffineTransform matrix_to_transform(CGContextRef cg, const SkMatrix& ctm) {    SkMatrix matrix;    matrix.setScale(1, -1);    matrix.postTranslate(0, SkIntToScalar(CGBitmapContextGetHeight(cg)));    matrix.preConcat(ctm);    return CGAffineTransformMake(matrix[SkMatrix::kMScaleX],                                 matrix[SkMatrix::kMSkewY],                                 matrix[SkMatrix::kMSkewX],                                 matrix[SkMatrix::kMScaleY],                                 matrix[SkMatrix::kMTransX],                                 matrix[SkMatrix::kMTransY]);}

void CFX_QuartzDeviceDriver::CG_SetImageTransform(int dest_left, int dest_top, int dest_width, int dest_height,        CGRect* rect ){    int flip_y = _foxitDevice2User.d * dest_height < 0 ? 1 : -1;    int flip_x = _foxitDevice2User.a * dest_width > 0 ? 1 : -1;    if (flip_y < 0 || flip_x < 0) {        if (dest_height < 0) {            dest_height = -dest_height;            dest_top -= dest_height;        }        CGRect rt = CGRectApplyAffineTransform(CGRectMake(dest_left, dest_top, dest_width, dest_height), _foxitDevice2User);        CGFloat offset_x = (rt.origin.x) + rt.size.width / 2.f,                offset_y = (rt.origin.y) + rt.size.height / 2.f;        CGAffineTransform transform = CGAffineTransformIdentity;        transform = CGAffineTransformConcat(transform, CGAffineTransformMake(1, 0, 0, 1, -offset_x, -offset_y));        transform = CGAffineTransformConcat(transform, CGAffineTransformMake(flip_x, 0, 0, flip_y, 0, 0));        transform = CGAffineTransformConcat(transform, CGAffineTransformMake(1, 0, 0, 1, offset_x, offset_y));        CGContextConcatCTM(_context, transform);        if (rect) {            *rect = CGRectApplyAffineTransform(*rect, transform);        }    }}

void CQuartz2D::setGraphicsTextMatrix(void* graphics, CFX_AffineMatrix* matrix){    if (!graphics || !matrix) {        return;    }    CGContextRef context = (CGContextRef) graphics;    CGFloat ty = CGBitmapContextGetHeight(context) - matrix->f;    CGContextSetTextMatrix(context, CGAffineTransformMake(matrix->a,                           matrix->b,                           matrix->c,                           matrix->d,                           matrix->e,                           ty));}

//-----------------------------------------------------------------------------void CGDrawContext::init (){    CGContextSaveGState (cgContext);    CGContextSetAllowsAntialiasing (cgContext, true);    CGContextSetAllowsFontSmoothing (cgContext, true);    CGContextSetAllowsFontSubpixelPositioning (cgContext, true);    CGContextSetAllowsFontSubpixelQuantization (cgContext, true);    CGContextSetShouldAntialias (cgContext, false);    CGContextSetFillColorSpace (cgContext, GetCGColorSpace ());    CGContextSetStrokeColorSpace (cgContext, GetCGColorSpace ());    CGContextSaveGState (cgContext);    CGAffineTransform cgCTM = CGAffineTransformMake (1.0, 0.0, 0.0, -1.0, 0.0, 0.0);    CGContextSetTextMatrix (cgContext, cgCTM);    CDrawContext::init ();}

static CGAffineTransform SkMatrixToCGAffineTransform(const SkMatrix& matrix){    // CGAffineTransforms don't support perspective transforms, so make sure    // we don't get those.    ASSERT(!matrix[SkMatrix::kMPersp0]);    ASSERT(!matrix[SkMatrix::kMPersp1]);    ASSERT(matrix[SkMatrix::kMPersp2] == 1.0f);    return CGAffineTransformMake(        matrix[SkMatrix::kMScaleX],        matrix[SkMatrix::kMSkewY],        matrix[SkMatrix::kMSkewX],        matrix[SkMatrix::kMScaleY],        matrix[SkMatrix::kMTransX],        matrix[SkMatrix::kMTransY]);}

static cairo_int_status_t_cairo_quartz_init_glyph_path (cairo_quartz_scaled_font_t *font,			       cairo_scaled_glyph_t *scaled_glyph){    cairo_quartz_font_face_t *font_face = _cairo_quartz_scaled_to_face(font);    CGGlyph glyph = _cairo_quartz_scaled_glyph_index (scaled_glyph);    CGAffineTransform textMatrix;    CGPathRef glyphPath;    CTFontRef ctFont;    cairo_path_fixed_t *path;    if (glyph == INVALID_GLYPH) {	_cairo_scaled_glyph_set_path (scaled_glyph, &font->base, _cairo_path_fixed_create());	return CAIRO_STATUS_SUCCESS;    }    /* scale(1,-1) * font->base.scale */    textMatrix = CGAffineTransformMake (font->base.scale.xx,					font->base.scale.yx,					-font->base.scale.xy,					-font->base.scale.yy,					0, 0);    // glyphPath = CGFontGetGlyphPathPtr (font_face->cgFont, &textMatrix, 0, glyph);    ctFont = CTFontCreateWithGraphicsFont (font_face->cgFont, 0.0, NULL, NULL);    glyphPath = CTFontCreatePathForGlyph (ctFont, glyph, &textMatrix);    CFRelease (ctFont);    if (!glyphPath)	return CAIRO_INT_STATUS_UNSUPPORTED;    path = _cairo_path_fixed_create ();    if (!path) {	CGPathRelease (glyphPath);	return _cairo_error(CAIRO_STATUS_NO_MEMORY);    }    CGPathApply (glyphPath, path, _cairo_quartz_path_apply_func);    CGPathRelease (glyphPath);    _cairo_scaled_glyph_set_path (scaled_glyph, &font->base, path);    return CAIRO_STATUS_SUCCESS;}

CFX_QuartzDeviceDriver::CFX_QuartzDeviceDriver(CGContextRef context, FX_INT32 deviceClass){    m_saveCount = 0;    _context		= context;    _deviceClass	= deviceClass;    CGContextRetain(_context);    CGRect r = CGContextGetClipBoundingBox(context);    _width	= FXSYS_round(r.size.width);    _height	= FXSYS_round(r.size.height);    _renderCaps = FXRC_SOFT_CLIP | FXRC_BLEND_MODE |                  FXRC_ALPHA_PATH | FXRC_ALPHA_IMAGE |                  FXRC_BIT_MASK | FXRC_ALPHA_MASK;    if (_deviceClass != FXDC_DISPLAY) {    } else {        CGImageRef image = CGBitmapContextCreateImage(_context);        if (image) {            _renderCaps |= FXRC_GET_BITS;            _width = CGImageGetWidth(image);            _height = CGImageGetHeight(image);            CGImageAlphaInfo alphaInfo = CGImageGetAlphaInfo(image);            if (kCGImageAlphaPremultipliedFirst == alphaInfo ||                    kCGImageAlphaPremultipliedLast == alphaInfo ||                    kCGImageAlphaOnly == alphaInfo) {                _renderCaps |= FXRC_ALPHA_OUTPUT;            }        }        CGImageRelease(image);    }    CGAffineTransform ctm = CGContextGetCTM(_context);    CGContextSaveGState(_context);    m_saveCount++;    if (ctm.d >= 0) {        CGFloat offset_x, offset_y;        offset_x = ctm.tx;        offset_y = ctm.ty;        CGContextTranslateCTM(_context, -offset_x, -offset_y);        CGContextConcatCTM(_context, CGAffineTransformMake(1, 0, 0, -1, offset_x, _height + offset_y));    }    _foxitDevice2User = CGAffineTransformIdentity;    _user2FoxitDevice = CGAffineTransformInvert(_foxitDevice2User);}

bool GiCanvasIos::drawImage(CGImageRef image, const Box2d& rectM){    CGContextRef context = m_draw->getContext();    bool ret = false;        if (context && image) {        Point2d ptD = rectM.center() * m_draw->xf().modelToDisplay();        Box2d rect = rectM * m_draw->xf().modelToDisplay();                CGAffineTransform af = CGAffineTransformMake(1, 0, 0, -1, 0, m_draw->height());        af = CGAffineTransformTranslate(af, ptD.x - rect.width() * 0.5f,                                         m_draw->height() - (ptD.y + rect.height() * 0.5f));                CGContextConcatCTM(context, af);        CGContextDrawImage(context, CGRectMake(0, 0, rect.width(), rect.height()), image);        CGContextConcatCTM(context, CGAffineTransformInvert(af));        ret = true;    }        return ret;}