Accumulates each primitive's input reach in device pixels, converting lengths with the same helpers and bounds the filter executors use. The executors round each primitive to whole pixels (offsets and morphology radii to the nearest pixel, blur kernels up), so each primitive's reach rounds up to whole pixels before the chain adds them. More...

#include "donner/svg/renderer/FilterRegionContext.h"

Public Member Functions
double	length (double value, int axis) const
	Device length of a nonnegative primitive length.
Vector2d	footprint (Vector2d axisPixels) const
	Device footprint of a reach measured in pixels along each filter axis. Under rotation or skew, the transformed blur path samples along the filter axes, which land on slanted device directions: each device axis gets the absolute linear coefficients times the user-space reach. Primitives that execute on the device raster read along the device axes instead, so the footprint keeps at least the per-axis reach.
Vector2d	offset (double dx, double dy) const
	Device extent of a primitive offset.
double	user (double value, int axis) const
	User-space value of a primitive length or offset.
Vector2d	localToDevice (Vector2d localPixels) const
	Device extent of local raster pixels, mapped through the filter's linear part.
Vector2d	offsetReach (double dx, double dy) const
	Reach of an offset: rounded to whole device pixels on the device raster, or rounded to whole local pixels on the local raster and mapped back.
Vector2d	blurReach (double stdDeviationX, double stdDeviationY) const
	Reach of a blur: three standard deviations, rounded up to whole pixels on the device raster or on the local raster.
void	add (const components::filter_primitive::GaussianBlur &blur)
	Wrapping edges read the opposite side of the input, which may lie anywhere in the region.
void	add (const components::filter_primitive::DropShadow &shadow)
void	add (const components::filter_primitive::Offset &value)
void	add (const components::filter_primitive::Morphology &morphology)
void	add (const components::filter_primitive::DisplacementMap &displacement)
	The backends disagree on how displacement scales: one applies the scale directly in raster pixels, the other multiplies it by the transform's area scale. Bound both. Both sample bilinearly, reading one pixel past the rounded-down displaced position.
void	add (const components::filter_primitive::ConvolveMatrix &convolve)
	Wrapping edges read the opposite side of the input, which may lie anywhere in the region.
void	add (const components::filter_primitive::DiffuseLighting &)
	Surface normals read the neighboring pixels.
void	add (const components::filter_primitive::SpecularLighting &)
	Surface normals read the neighboring pixels.
template<typename T>
void	add (const T &)
	Point-wise primitives read only the input pixel under each output pixel.
void	addTile (const components::FilterNode *input)
	feTile repeats its input's subregion, so the capture must cover that whole rectangle. It is known here only when the input primitive authors its region in user-space units; otherwise the tile may read anywhere in the filter region.

Static Public Member Functions
static Vector2d	wholePixels (Vector2d pixels)
	Round a reach up to whole pixels.

Public Attributes
Transform2d	deviceFromFilter
	Filter user space to raster pixels.
Vector2d	scale
	Device scale of each filter axis.
Vector2d	localScale
	Scale of the transformed path's local raster.
Vector2d	bounds
	Element bounding box size, or 1 without one.
bool	objectBounds = false
	Whether primitive lengths are bounding-box fractions.
FilterInputMargin	margin
	Accumulated margin.

Detailed Description

Accumulates each primitive's input reach in device pixels, converting lengths with the same helpers and bounds the filter executors use. The executors round each primitive to whole pixels (offsets and morphology radii to the nearest pixel, blur kernels up), so each primitive's reach rounds up to whole pixels before the chain adds them.

Blur-family graphs under rotation or skew may instead run on the transformed path's local raster, scaled by each filter axis's length, where blurs and offsets round in local pixels before the result maps back to the device. Their reach is the larger of the two.

Member Function Documentation

◆ blurReach()

Vector2d donner::svg::FilterInputMarginBuilder::blurReach	(	double	stdDeviationX,
		double	stdDeviationY ) const

inline

Reach of a blur: three standard deviations, rounded up to whole pixels on the device raster or on the local raster.

Parameters

stdDeviationX	X deviation.
stdDeviationY	Y deviation.

◆ footprint()

Vector2d donner::svg::FilterInputMarginBuilder::footprint ( Vector2d axisPixels ) const

inline

Device footprint of a reach measured in pixels along each filter axis. Under rotation or skew, the transformed blur path samples along the filter axes, which land on slanted device directions: each device axis gets the absolute linear coefficients times the user-space reach. Primitives that execute on the device raster read along the device axes instead, so the footprint keeps at least the per-axis reach.

Parameters

axisPixels Reach in pixels along the filter X and Y axes.

◆ length()

double donner::svg::FilterInputMarginBuilder::length	(	double	value,
		int	axis ) const

inline

Device length of a nonnegative primitive length.

Parameters

value	Length.
axis	0 or 1.

◆ localToDevice()

Vector2d donner::svg::FilterInputMarginBuilder::localToDevice ( Vector2d localPixels ) const

inline

Device extent of local raster pixels, mapped through the filter's linear part.

Parameters

localPixels Signed local raster pixels along each filter axis.

◆ offset()

Vector2d donner::svg::FilterInputMarginBuilder::offset	(	double	dx,
		double	dy ) const

inline

Device extent of a primitive offset.

Parameters

dx	X offset.
dy	Y offset.

◆ offsetReach()

Vector2d donner::svg::FilterInputMarginBuilder::offsetReach	(	double	dx,
		double	dy ) const

inline

Reach of an offset: rounded to whole device pixels on the device raster, or rounded to whole local pixels on the local raster and mapped back.

Parameters

dx	X offset.
dy	Y offset.

◆ user()

double donner::svg::FilterInputMarginBuilder::user	(	double	value,
		int	axis ) const

inline

User-space value of a primitive length or offset.

Parameters

value	Value.
axis	0 or 1.

◆ wholePixels()

Vector2d donner::svg::FilterInputMarginBuilder::wholePixels ( Vector2d pixels )

inlinestatic

Round a reach up to whole pixels.

Parameters

pixels Reach per axis.

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

donner/svg/renderer/FilterRegionContext.h

Public Member Functions

Static Public Member Functions

Public Attributes

Detailed Description

Member Function Documentation

◆ blurReach()

◆ footprint()

◆ length()

◆ localToDevice()

◆ offset()

◆ offsetReach()

◆ user()

◆ wholePixels()