nsISVGRendererGlyphMetrics Interface Reference
[Rendering Engine Interfaces]

import "nsISVGRendererGlyphMetrics.idl";

Inheritance diagram for nsISVGRendererGlyphMetrics:

[legend]List of all members.

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Detailed Description

One of a number of interfaces (all starting with nsISVGRenderer*) to be implemented by an SVG rendering engine. See nsISVGRenderer for more details.

The SVG rendering backend uses this interface to communicate to the rendering engine-native glyph metrics objects.

A glyph metrics object is instantiated by the backend for a given nsISVGGlyphMetricsSource object with a call to nsISVGRenderer::createGlyphMetrics(). The glyph metrics object is assumed to store a reference to its associated source object and provide metrics information about the (composite) glyph described by nsISVGGlyphMetricsSource::characterData, nsISVGGlyphMetricsSource::font, nsISVGGlyphMetricsSource::CTM, and other relevant style such as nsISVGGlyphMetricsSource::strokeWidth.

Definition at line 66 of file nsISVGRendererGlyphMetrics.idl.

Public Member Functions

• nsIDOMSVGRect getExtentOfChar (in unsigned long charnum)
• float getBaselineOffset (in unsigned short baselineIdentifier)
• boolean update (in unsigned long updatemask)

Public Attributes

• readonly attribute float advance
• readonly attribute nsIDOMSVGRect boundingBox

Baseline offset constants for getBaselineOffset()

• const unsigned short BASELINE_ALPHABETIC = 0
• const unsigned short BASELINE_HANGING = 1
• const unsigned short BASELINE_IDEOGRAPHC = 2
• const unsigned short BASELINE_MATHEMATICAL = 3
• const unsigned short BASELINE_CENTRAL = 4
• const unsigned short BASELINE_MIDDLE = 5
• const unsigned short BASELINE_TEXT_BEFORE_EDGE = 6
• const unsigned short BASELINE_TEXT_AFTER_EDGE = 7

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Member Function Documentation

nsIDOMSVGRect nsISVGRendererGlyphMetrics::getExtentOfChar (  in unsigned long  charnum  )

Get the untransformed bounding box of an individual glyph. Parameters: charnum  The index of the character in nsISVGGlyphMetricsSource::characterData whose glyph bounding box is to be determined Returns: The untransformed bounding box in pixel coordinates

float nsISVGRendererGlyphMetrics::getBaselineOffset (  in unsigned short  baselineIdentifier  )

Retrieve the (y-axis) offset of the given baseline. Parameters: baselineIdentifier  One of the BASELINE_* constants defined in this interface. Returns: Y-axis offset in pixels relative to top of bounding box.

boolean nsISVGRendererGlyphMetrics::update (  in unsigned long  updatemask  )

Called by this object's corresponding nsISVGGlyphMetricsSource as a notification that some of the source's data (identified by paramter 'updatemask') has changed. Parameters: updatemask  An OR-ed combination of the UPDATEMASK_* constants defined in nsISVGGlyphMetricsSource. Returns: PR_TRUE if the metrics have changed as a result of the source update, PR_FALSE otherwise.

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Member Data Documentation

readonly attribute float nsISVGRendererGlyphMetrics::advance

Untransformed width of the composite glyph in pixels. Definition at line 71 of file nsISVGRendererGlyphMetrics.idl. Referenced by nsSVGLibartGlyphMetricsFT::GetBoundingMetrics().

readonly attribute nsIDOMSVGRect nsISVGRendererGlyphMetrics::boundingBox

Untransformed bounding box of the composite glyph in pixel coordinates. Definition at line 77 of file nsISVGRendererGlyphMetrics.idl.

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_ALPHABETIC = 0

Definition at line 93 of file nsISVGRendererGlyphMetrics.idl. Referenced by nsSVGLibartGlyphMetricsFT::GetBaselineOffset(), nsSVGLibartGlyphMetrics::GetBaselineOffset(), and nsSVGGDIPlusGlyphMetrics::GetBaselineOffset().

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_HANGING = 1

Definition at line 94 of file nsISVGRendererGlyphMetrics.idl.

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_IDEOGRAPHC = 2

Definition at line 95 of file nsISVGRendererGlyphMetrics.idl.

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_MATHEMATICAL = 3

Definition at line 96 of file nsISVGRendererGlyphMetrics.idl.

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_CENTRAL = 4

Definition at line 97 of file nsISVGRendererGlyphMetrics.idl. Referenced by nsSVGLibartGlyphMetricsFT::GetBaselineOffset(), nsSVGLibartGlyphMetrics::GetBaselineOffset(), and nsSVGGDIPlusGlyphMetrics::GetBaselineOffset().

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_MIDDLE = 5

Definition at line 98 of file nsISVGRendererGlyphMetrics.idl. Referenced by nsSVGLibartGlyphMetricsFT::GetBaselineOffset(), nsSVGLibartGlyphMetrics::GetBaselineOffset(), and nsSVGGDIPlusGlyphMetrics::GetBaselineOffset().

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_TEXT_BEFORE_EDGE = 6

Definition at line 99 of file nsISVGRendererGlyphMetrics.idl. Referenced by nsSVGLibartGlyphMetricsFT::GetBaselineOffset(), nsSVGLibartGlyphMetrics::GetBaselineOffset(), and nsSVGGDIPlusGlyphMetrics::GetBaselineOffset().

const unsigned short nsISVGRendererGlyphMetrics::BASELINE_TEXT_AFTER_EDGE = 7

Definition at line 100 of file nsISVGRendererGlyphMetrics.idl. Referenced by nsSVGLibartGlyphMetricsFT::GetBaselineOffset(), nsSVGLibartGlyphMetrics::GetBaselineOffset(), and nsSVGGDIPlusGlyphMetrics::GetBaselineOffset().

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The documentation for this interface was generated from the following file:

• /layout/svg/renderer/public/nsISVGRendererGlyphMetrics.idl

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