#include <cartotype_graphics.h>

Inheritance diagram for CartoType::CGraphicsContext:

Public Types
enum	{ EDrawShapeAntiAlias = 1, EDrawShape6BitFractionalPixels = 2, EDrawShapeEvenOddFill = 4 }
Public Member Functions
virtual void	Sync ()=0
virtual TResult	DrawBitmap (const TBitmap &aBitmap, const TPoint &aTopLeft)=0
virtual TResult	DrawShape (const MPath &aPath, uint32 aFlags)=0
virtual void	Clear ()=0
virtual CT_IMPORT TResult	DrawRect (const TRect &aRect)
virtual CT_IMPORT bool	TransformsPoints ()
virtual CT_IMPORT TResult	Transform (TPoint &aPoint, int32 aFractionalBits)
virtual CT_IMPORT void	InverseTransform (TPoint &aPoint, int32 aFractionalBits)
virtual CT_IMPORT bool	EnableTransform (bool aEnable)
virtual CT_IMPORT void	OnViewResize (int32 aWidth, int32 aHeight)
virtual CT_IMPORT TBitmap *	Bitmap ()
virtual CT_IMPORT TBitmap *	PushBitmap (TResult &aError)
virtual CT_IMPORT TResult	PopBitmap (TBitmap *aBitmap)
virtual CT_IMPORT TBitmap *	DeleteButKeepBitmap (CGraphicsContext *&aGc)
virtual CT_IMPORT TResult	DrawTexture (const CTexture &aTexture, const TPointFP &aTopLeft, const TTransformFP &aTransform)
virtual CT_IMPORT TResult	DrawStroke (const MPath &aPath, uint32 aFlags, const TTransform *aTransform=NULL)
CT_IMPORT TResult	DrawShapeAndStroke (const MPath &aPath, uint32 aFlags, const TPaint &aStrokePaint, const TTransform *aTransform=NULL)
CT_IMPORT void	SetClip (const TRect &aClip)
CT_IMPORT void	SetColor (TColor aColor)
CT_IMPORT void	SetPaintServer (MPaintServer *aPaintServer)
CT_IMPORT void	SetPaint (const TPaint &aPaint)
CT_IMPORT void	SetAlpha (int32 aAlpha)
CT_IMPORT void	SetCompositingOp (TCompositingOp aOp)
CT_IMPORT void	SetTextureMask (TColor aColor)
CT_IMPORT void	SetParam (TGraphicsParam &aParam)
CT_IMPORT void	SetPen (const TCircularPen &aPen)
CT_IMPORT TResult	DrawLoggedText (int32 aIndex)
CT_IMPORT void	InverseTransformRect (TRect &aRect, int32 aFractionalBits)
CEngine &	Engine ()
const TRect &	Clip () const
const TPaint &	Paint () const
TColor	Color () const
int32	Alpha () const
const TRect &	Bounds () const
MPaintServer *	PaintServer () const
void	SetPalette (const MPalette *aPalette)
const MPalette *	Palette () const
const TCircularPen &	Pen () const
void	SetDashArray (const CDashArray *aDashArray)
const CDashArray *	DashArray () const
const TGraphicsParam &	Param () const
Static Public Member Functions
static uint8	MultiplyIntensities (int aIntensity1, int aIntensity2)
static uint8	AlphaBlend (int aForeground, int aBackground, int aAlpha)
Protected Types
enum	{ EClipChanged = 1, EPaintChanged = 2, EGlowColorChanged = 4, ECompositingOpChanged = 8, ETextureMaskChanged = 16, EAllChanged = -1 }
Protected Member Functions
TResult	DrawDashedStroke (const MPath &aPath, uint32 aFlags, const TTransform *aTransform)
	CGraphicsContext (CEngine &aEngine, const TRect &aBounds)
Protected Attributes
CEngine &	iEngine
TGraphicsParam	iParam
TRect	iBounds
int32	iChangeFlags

Detailed Description

The base graphics context class. A graphics context draws to a raster drawing surface with square pixels.

Member Enumeration Documentation

anonymous enum

Flags used when drawing shapes.

Enumerator:

EDrawShapeAntiAlias	Use 8-bit anti-aliasing when drawing a shape. The default is monochrome rendering.
EDrawShape6BitFractionalPixels	Use 26.6 fixed-point pixel coordinates (i.e. 64ths of pixels) when drawing a shape. The default is whole-pixel coordinates.
EDrawShapeEvenOddFill	Use the even-odd fill rule when drawing shape. the default is the non-zero winding rule.

anonymous enum [protected]

Bit values for iChangeFlags.

Enumerator:

EClipChanged	The clip rectangle has changed.
EPaintChanged	The paint has changed.
EGlowColorChanged	The glow color, if any, has changed.
ECompositingOpChanged	The compositing operation has changed.
ETextureMaskChanged	The texture mask has changed.
EAllChanged	All graphics parameters have changed; the internal state must be completely initialised.

Constructor & Destructor Documentation

CartoType::CGraphicsContext::CGraphicsContext	(	CEngine &	aEngine,
		const TRect &	aBounds
	)		`[inline, protected]`

Construct a graphics context to draw into aBounds.

Member Function Documentation

int32 CartoType::CGraphicsContext::Alpha ( ) const [inline]

Return the current alpha (opacity) level as a number in the range 0 ... 255.

static uint8 CartoType::CGraphicsContext::AlphaBlend	(	int	aForeground,
		int	aBackground,
		int	aAlpha
	)		`[inline, static]`

Blend aForeground and aBackground in the proportion aAlpha. All three numbers are intensities in the range 0...255.

CT_EXPORT TBitmap * CGraphicsContext::Bitmap ( ) [virtual]

Return the bitmap drawn to by the graphics context, if any. If the graphics context does not draw to a bitmap return NULL. The default implementation returns null.

Reimplemented in CartoType::CBitmapGraphicsContext, and CartoType::CPerspectiveGraphicsContext.

const TRect& CartoType::CGraphicsContext::Bounds ( ) const [inline]

Return the rectangle that the graphics context draws to if no clipping is done.

virtual void CartoType::CGraphicsContext::Clear ( ) [pure virtual]

Clear the drawing area to transparent black. If colors are not stored set all pixels to zero intensity. If transparency levels are not stored set all pixels to black.

Implemented in CartoType::C8BitTwinBitmapGraphicsContext, CartoType::C8BitMonoBitmapGraphicsContext, CartoType::C32BitColorBitmapGraphicsContext, CartoType::C24BitColorBitmapGraphicsContext, CartoType::C16BitColorBitmapGraphicsContext, CartoType::TTestZGraphicsContext, CartoType::TTestLabelGraphicsContext, CartoType::CPerspectiveGraphicsContext, and CartoType::COpenGlGraphicsContext.

const TRect& CartoType::CGraphicsContext::Clip ( ) const [inline]

Return the clipping rectangle.

TColor CartoType::CGraphicsContext::Color ( ) const [inline]

Return the current color as an RGBA value including the alpha channel.

const CDashArray* CartoType::CGraphicsContext::DashArray ( ) const [inline]

Return the current dash array.

CT_EXPORT TBitmap * CGraphicsContext::DeleteButKeepBitmap ( CGraphicsContext *& aGc ) [virtual]

Delete the graphics context, setting the pointer aGc to null, but preserve and return its bitmap. Do nothing if the operation is impossible. The base implementation does nothing.

Reimplemented in CartoType::CBitmapGraphicsContext.

virtual TResult CartoType::CGraphicsContext::DrawBitmap	(	const TBitmap &	aBitmap,
		const TPoint &	aTopLeft
	)		`[pure virtual]`

Draw a bitmap. If the bitmap has no color information use the current color. Combine any alpha information from the bitmap with the current alpha level. The coordinates are whole pixels.

Implemented in CartoType::C8BitTwinBitmapGraphicsContext, CartoType::C8BitMonoBitmapGraphicsContext, CartoType::C32BitColorBitmapGraphicsContext, CartoType::C24BitColorBitmapGraphicsContext, CartoType::C16BitColorBitmapGraphicsContext, CartoType::TTestZGraphicsContext, CartoType::TTestLabelGraphicsContext, CartoType::CPerspectiveGraphicsContext, and CartoType::COpenGlGraphicsContext.

CT_EXPORT TResult CGraphicsContext::DrawLoggedText ( int32 aIndex )

Redraw previous characters at identical positions, starting at logged character aIndex.

CT_EXPORT TResult CGraphicsContext::DrawRect ( const TRect & aRect ) [virtual]

Draw a filled rectangle in the current color. The coordinates are whole pixels.

Reimplemented in CartoType::C8BitTwinBitmapGraphicsContext, CartoType::C8BitMonoBitmapGraphicsContext, CartoType::C32BitColorBitmapGraphicsContext, CartoType::C24BitColorBitmapGraphicsContext, CartoType::C16BitColorBitmapGraphicsContext, CartoType::TTestZGraphicsContext, CartoType::TTestLabelGraphicsContext, and CartoType::CPerspectiveGraphicsContext.

virtual TResult CartoType::CGraphicsContext::DrawShape	(	const MPath &	aPath,
		uint32	aFlags
	)		`[pure virtual]`

Draw a filled shape in the current color.

Implemented in CartoType::C8BitTwinBitmapGraphicsContext, CartoType::C8BitMonoBitmapGraphicsContext, CartoType::C32BitColorBitmapGraphicsContext, CartoType::C24BitColorBitmapGraphicsContext, CartoType::C16BitColorBitmapGraphicsContext, CartoType::TTestZGraphicsContext, CartoType::TTestLabelGraphicsContext, CartoType::CPerspectiveGraphicsContext, and CartoType::COpenGlGraphicsContext.

CT_EXPORT TResult CGraphicsContext::DrawShapeAndStroke	(	const MPath &	aPath,
		uint32	aFlags,
		const TPaint &	aStrokePaint,
		const TTransform *	aTransform = `NULL`
	)

Fill and outline a shape. The shape is filled if the current paint is non-null, and outlined if aStrokePaint is non-null. Optionally apply a transform to the shape and the stroke envelope.

CT_EXPORT TResult CGraphicsContext::DrawStroke	(	const MPath &	aPath,
		uint32	aFlags,
		const TTransform *	aTransform = `NULL`
	)		`[virtual]`

Draw a stroke using the current circular pen.

Optionally apply a transform to the stroke envelope before drawing it. The offsets in the transform (the Tx and Ty components) are always in pixels, whether or not (aFlags & EDrawShape6BitFractionalPixels) is true.

CT_EXPORT TResult CGraphicsContext::DrawTexture	(	const CTexture &	aTexture,
		const TPointFP &	aTopLeft,
		const TTransformFP &	aTransform
	)		`[virtual]`

Draw a texture at aTopLeft, transforming it by aTransform. The baseimplementation returns KErrorUnimplemented.

Reimplemented in CartoType::C32BitColorBitmapGraphicsContext, and CartoType::TTestLabelGraphicsContext.

CT_EXPORT bool CGraphicsContext::EnableTransform ( bool aEnable ) [virtual]

Enable or disable any transformation applied by the graphics context. Return the previous state. The base implementation does nothing and returns false.

Reimplemented in CartoType::CPerspectiveGraphicsContext.

CEngine& CartoType::CGraphicsContext::Engine ( ) [inline]

Return a reference to the singleton graphics engine.

CT_EXPORT void CGraphicsContext::InverseTransform	(	TPoint &	aPoint,
		int32	aFractionalBits
	)		`[virtual]`

Apply the inverse of the graphics context's current transformation to a point. See CGraphicsContext::Transform function for details.

Reimplemented in CartoType::CPerspectiveGraphicsContext.

CT_EXPORT void CGraphicsContext::InverseTransformRect	(	TRect &	aRect,
		int32	aFractionalBits
	)

Apply the inverse of the graphics context's current transformation to a rectangle and normalise the rectangle so that left < right and top < bottom.

static uint8 CartoType::CGraphicsContext::MultiplyIntensities	(	int	aIntensity1,
		int	aIntensity2
	)		`[inline, static]`

Multiply two intensities, treated as fractions in the range 0...255.

CT_EXPORT void CGraphicsContext::OnViewResize	(	int32	aWidth,
		int32	aHeight
	)		`[virtual]`

Do anything that is needed when the output view size is initially set or changed. For instance, the OpenGL graphics context needs to change its viewport and projection. The base implementation does nothing.

Reimplemented in CartoType::CPerspectiveGraphicsContext, and CartoType::COpenGlGraphicsContext.

const TPaint& CartoType::CGraphicsContext::Paint ( ) const [inline]

Return the current paint.

MPaintServer* CartoType::CGraphicsContext::PaintServer ( ) const [inline]

Return the current paint server, or null if no paint server is in use.

const MPalette* CartoType::CGraphicsContext::Palette ( ) const [inline]

Return the current palette, or null if no palette is in use. Palettes are used only when drawing bitmaps requiring them.

const TGraphicsParam& CartoType::CGraphicsContext::Param ( ) const [inline]

Return the current graphics parameters.

const TCircularPen& CartoType::CGraphicsContext::Pen ( ) const [inline]

Return the pen used for drawing strokes.

CT_EXPORT TResult CGraphicsContext::PopBitmap ( TBitmap * aBitmap ) [virtual]

Draw the current bitmap on top of aBitmap before deleting it and restoring aBitmap as the current bitmap. The base implementation does nothing.

Reimplemented in CartoType::CBitmapGraphicsContext, and CartoType::CPerspectiveGraphicsContext.

CT_EXPORT TBitmap * CGraphicsContext::PushBitmap ( TResult & aError ) [virtual]

Replace the current bitmap with a new one of the same type and size, returning the original one. The base implementation does nothing.

Reimplemented in CartoType::CBitmapGraphicsContext, and CartoType::CPerspectiveGraphicsContext.

CT_EXPORT void CGraphicsContext::SetAlpha ( int32 aAlpha )

Set the alpha (transparency) level, where 0 = transparent and 255 = opaque.

CT_EXPORT void CGraphicsContext::SetColor ( TColor aColor )

Set the color used for painting and set the paint server to null.

CT_EXPORT void CGraphicsContext::SetCompositingOp ( TCompositingOp aOp )

Set the compositing op. Note that most graphics contexts support only one compositing op, 'over' (EOverCompositingOp).

void CartoType::CGraphicsContext::SetDashArray ( const CDashArray * aDashArray ) [inline]

Set the array of dash and gap sizes used for dashed strokes.

CT_EXPORT void CGraphicsContext::SetPaint ( const TPaint & aPaint )

Set the color and the paint server.

CT_EXPORT void CGraphicsContext::SetPaintServer ( MPaintServer * aPaintServer )

Set the paint server. A value of null tells the graphics context not to use a paint server but to use the current color.

void CartoType::CGraphicsContext::SetPalette ( const MPalette * aPalette ) [inline]

Set the palette. A value of null tells the graphics context not to use a palette, in which case bitmaps requiring palettes cannot be drawn.

CT_EXPORT void CGraphicsContext::SetParam ( TGraphicsParam & aParam )

Set the graphics parameters to the values in aParam.

CT_EXPORT void CGraphicsContext::SetPen ( const TCircularPen & aPen )

Set the pen used for drawing strokes.

CT_EXPORT void CGraphicsContext::SetTextureMask ( TColor aColor )

Set the texture mask color: the color that prevents texture pixels from being drawn in unwanted areas like the sea.

virtual void CartoType::CGraphicsContext::Sync ( ) [pure virtual]

Synchronize the private graphics state to take account of any changes in iChangeFlags.

Implemented in CartoType::C8BitTwinBitmapGraphicsContext, CartoType::C8BitMonoBitmapGraphicsContext, CartoType::C32BitColorBitmapGraphicsContext, CartoType::C24BitColorBitmapGraphicsContext, CartoType::C16BitColorBitmapGraphicsContext, CartoType::TTestZGraphicsContext, CartoType::TTestLabelGraphicsContext, CartoType::CPerspectiveGraphicsContext, and CartoType::COpenGlGraphicsContext.

CT_EXPORT TResult CGraphicsContext::Transform	(	TPoint &	aPoint,
		int32	aFractionalBits
	)		`[virtual]`

Apply the graphics context's current transformation to a point. Graphics contexts that provide a non-identity overriding implementation of this function must also override TransformsPoints to return true. The base implementation is identity and thus does nothing. Although the transform does not change the points' representation, the number of fractional bits must be supplied so that the transform can use actual pixels consistently, as in a perpective transform.

Reimplemented in CartoType::CPerspectiveGraphicsContext.

CT_EXPORT bool CGraphicsContext::TransformsPoints ( ) [virtual]

Return true if the GC applies a further transformation to points before drawing them, as for example the perspective transformation. The base implementation returns false.

Reimplemented in CartoType::CPerspectiveGraphicsContext.