Printing and Image Generation

This group contains methods used for printing, generating PostScript output and saving images. More...

Detailed Description

This group contains methods used for printing, generating PostScript output and saving images.

Functions
GlgBoolean	ExportPostScript (char *filename="out.ps", double x=0., double y=0., double width=2000., double height=2000., GlgBoolean portrait=True, GlgBoolean stretch=True, GlgBoolean center=True)
	Generates a PostScript output of the current state of the viewport's graphics. More...
PlatformDependent	GenerateImage (char *resource_name=NULL, PlatformDependent image=NULL)
	Creates and returns an image of the current state of the viewport's graphics. More...
PlatformDependent	GenerateImageCustom (char *resource_name, PlatformDependent image, GlgLong x, GlgLong y, GlgLong width, GlgLong height, GlgLong gap)
	Creates an image of the specified rectangular region of the viewport's graphics. More...
void	OnDrawMetafile (CDC *print_dc)
	Windows only: Provides MFC metafile output support. More...
void	OnPrint (CDC *print_dc)
	Windows only: Provides MFC printing support. More...
GlgBoolean	Print (PlatformDependent print_context, double x=0., double y=0., double width=2000., double height=2000., GlgBoolean portrait=True, GlgBoolean stretch=True, GlgBoolean center=True)
	GTK and Windows only: Generates printing output of the current state of the viewport's graphics. More...
GlgBoolean	SaveImage (char *resource_name, char *filename, GlgImageFormat format=GLG_JPEG)
	Generates a JPEG or PNG image of the current state of this viewport's graphics and saves it to a file. More...
GlgBoolean	SaveImageCustom (char *resource_name, char *filename, GlgImageFormat format, GlgLong x, GlgLong y, GlgLong width, GlgLong height, GlgLong gap)
	Generates a JPEG or PNG image of the specified rectangular region of the viewport's graphics and saves it to a file. More...

Function Documentation

ExportPostScript()

GlgBoolean ExportPostScript	(	char *	filename = "out.ps",
		double	x = 0.,
		double	y = 0.,
		double	width = 2000.,
		double	height = 2000.,
		GlgBoolean	portrait = True,
		GlgBoolean	stretch = True,
		GlgBoolean	center = True
	)

Generates a PostScript output of the current state of the viewport's graphics.

This is a wrapper for GlgExportPostScript, which receives the method's parameters. See GlgExportPostScript for parameter descriptions.

Parameters

filename	See GlgExportPostScript for parameter description.
x,y	See GlgExportPostScript for parameter description.
width,height	See GlgExportPostScript for parameter description.
portrait	See GlgExportPostScript for parameter description.
stretch	See GlgExportPostScript for parameter description.
center	See GlgExportPostScript for parameter description.

Returns

Success or failure status.

The drawing's hierarchy must be set up in order to generate PostScript output. Use Update before calling ExportPostScript to make sure the drawing is up to date.

GenerateImage()

PlatformDependent GenerateImage	(	char *	resource_name = NULL,
		PlatformDependent	image = NULL
	)

Creates and returns an image of the current state of the viewport's graphics.

This is a wrapper for GlgGenerateImage.

Parameters

resource_name	Specifies the resource path of a child viewport whose image to save, or NULL to save the image of this viewport. The resource path is relative to this viewport.
image	If not NULL, specifies a platform-dependent image to be used. This image will be filled and returned instead of creating and returning a new image. The type of the image is platform-dependent: cairo_surface_t* in GTK Pixmap on X11 HBITMAP on Windows.

Returns

The generated image or NULL if image generation failed. The type of the returned image is platform-dependent:

• cairo_surface_t* in GTK
• Pixmap on X11
• HBITMAP on Windows.

GenerateImage creates an image of the visible part of the viewport, clipping out the parts of the drawing that extends outside of it.

For a light viewport, the output will be generated for its parent viewport. The drawing's hierarchy must be set up in order to generate an image.

GenerateImageCustom()

PlatformDependent GenerateImageCustom	(	char *	resource_name,
		PlatformDependent	image,
		GlgLong	x,
		GlgLong	y,
		GlgLong	width,
		GlgLong	height,
		GlgLong	gap
	)

Creates an image of the specified rectangular region of the viewport's graphics.

This is a wrapper for GlgGenerateImageCustom.

Parameters

resource_name	Specifies the resource path of a child viewport whose image to save, or NULL to save the image of this viewport. The resource path is relative to this viewport.
image	If not NULL, specifies a platform-dependent image to be used. This image will be filled and returned instead of creating and returning a new image. The type of the image is platform-dependent: cairo_surface_t* in GTK Pixmap on X11 HBITMAP on Windows.
x	Specifies the X coordinate of the area used for generating an image. It defines an offset in screen pixels relative to the origin of the viewport's window, which has screen coordinates of (0,0).
y	Specifies the Y coordinate of the area used for generating an image. It defines an offset in screen pixels relative to the origin of the viewport's window, which has screen coordinates of (0,0).
width	Specifies the width in screen pixels of the area used for generating an image.
height	Specifies the height in screen pixels of the area used for generating an image.
gap	Specifies the padding space between the extent of the drawing and the border of the generated image in case when zero width and height parameters are specified.

Returns

The generated image or NULL if image generation failed. The type of the returned image is platform-dependent:

• cairo_surface_t* in GTK
• Pixmap on X11
• HBITMAP on Windows.

The x, y, width and height parameters may be obtained by querying the bounding box of either the whole drawing or of the area of the drawing for which the image needs to be generated using GetBoxPtr.

If width and height parameters are 0, the image of the whole drawing is generated using the drawing's bounding rectangle as the image generation area, without clipping to just the visible area. If the viewport is zoomed in, this area may be significantly bigger than the visible area of the viewport, and the image size may be quite large. The viewport's zoom factor defines the scaling factor for objects in the drawing when the image is saved.

For a light viewport, the output will be generated for its parent viewport. The drawing's hierarchy must be set up in order to generate an image.

OnDrawMetafile()

void OnDrawMetafile

(

CDC *

print_dc

)

Windows only: Provides MFC metafile output support.

Is used by the MFC container's OnDrawMetafile method to produce metafile for the GLG child window.

If this object is a light viewport, the output will be generated for its parent viewport.

Parameters

print_dc

Specifies the printing device context for metafile output.

OnPrint()

void OnPrint

(

CDC *

print_dc

)

Windows only: Provides MFC printing support.

Is used by the MFC container's OnPrint method to print GLG child window. This is a wrapper for GlgOnPrint.

If this object is a light viewport, the output will be generated for its parent viewport.

Parameters

print_dc

Specifies the printing device context.

Print()

GlgBoolean Print	(	PlatformDependent	print_context,
		double	x = 0.,
		double	y = 0.,
		double	width = 2000.,
		double	height = 2000.,
		GlgBoolean	portrait = True,
		GlgBoolean	stretch = True,
		GlgBoolean	center = True
	)

GTK and Windows only: Generates printing output of the current state of the viewport's graphics.

This is a wrapper for GlgNativePrint, which receives the method's parameters. See GlgNativePrint for parameter descriptions.

The drawing's hierarchy must be set up in order to print the drawing. Use Update before printing to make sure the drawing is up to date.

In the MFC environment on Windows, OnPrint may be used to support printing of the GlgControlC MFC wrapper.

Parameters

print_context	See GlgExportPostScript for parameter description.
x,y	See GlgExportPostScript for parameter description.
width,height	See GlgExportPostScript for parameter description.
portrait	See GlgExportPostScript for parameter description.
stretch	See GlgExportPostScript for parameter description.
center	See GlgExportPostScript for parameter description.

Returns

Success or failure status.

SaveImage()

GlgBoolean SaveImage	(	char *	resource_name,
		char *	filename,
		GlgImageFormat	format = GLG_JPEG
	)

Generates a JPEG or PNG image of the current state of this viewport's graphics and saves it to a file.

This is a wrapper for GlgSaveImage.

Parameters

resource_name	Specifies the resource path of a child viewport whose image to save, or NULL to save the image of this viewport. The resource path is relative to this viewport.
filename	Specifies a filename in which to save the generated image.
format	Specifies an image format, must be GLG_JPEG or GLG_PNG.

Returns

True if the image was successfully saved, otherwise False.

SaveImage saves an image of the visible part of the viewport, clipping out the parts of the drawing that extends outside of it.

For a light viewport, the output will be generated for its parent viewport. The drawing's hierarchy must be set up in order to generate an image.

SaveImageCustom()

GlgBoolean SaveImageCustom	(	char *	resource_name,
		char *	filename,
		GlgImageFormat	format,
		GlgLong	x,
		GlgLong	y,
		GlgLong	width,
		GlgLong	height,
		GlgLong	gap
	)

Generates a JPEG or PNG image of the specified rectangular region of the viewport's graphics and saves it to a file.

This is a wrapper for GlgSaveImageCustom.

Parameters

resource_name	Specifies the resource path of a child viewport whose image to save, or NULL to save the image of this viewport. The resource path is relative to this viewport.
filename	Specifies a filename in which to save the generated image.
format	Specifies an image format, must be GLG_JPEG or GLG_PNG.
x	Specifies the X coordinate of the area used for generating an image. It defines an offset in screen pixels relative to the origin of the viewport's window, which has screen coordinates of (0,0).
y	Specifies the Y coordinate of the area used for generating an image. It defines an offset in screen pixels relative to the origin of the viewport's window, which has screen coordinates of (0,0).
width	Specifies the width in screen pixels of the area used for generating an image.
height	Specifies the height in screen pixels of the area used for generating an image.
gap	Specifies the padding space between the extent of the drawing and the border of the generated image in case when zero width and height parameters are specified.

Returns

True if the image was successfully saved, otherwise False.

The x, y, width and height parameters may be obtained by querying the bounding box of either the whole drawing or of the area of the drawing for which the image needs to be generated using GetBoxPtr.

If width and height parameters are 0, the image of the whole drawing is generated using the drawing's bounding rectangle as the image generation area, without clipping to just the visible area. If the viewport is zoomed in, this area may be significantly bigger than the visible area of the viewport, and the image size may be quite large. The viewport's zoom factor defines the scaling factor for objects in the drawing when the image is saved.

For a light viewport, the output will be generated for its parent viewport. The drawing's hierarchy must be set up in order to generate an image.