slr::SlrShadingContext Class Reference

Public Member Functions
uint32_t	threadIdx () const
	Thread index from current SlrThreadContext.
SlrScene *	motionScene () const
SlrScene *	motionScene0 () const
SlrScene *	motionScene1 () const
const fdk::Mat4d &	matrix (int n) const
const fdk::Mat4d &	matrix0 (int n) const
const fdk::Mat4d &	matrix1 (int n) const
SlrRayTestCache *	rayTestCache () const
void	setRayTestCache (SlrRayTestCache *r)
float	getPolygonEdgeDistance (const fdk::Vec4f &P, float minDist) const
bool	shadeBothSides () const
	Shade both sides of surface (front and back) ignoring surface normal to camera.
bool	shadeFrontOnly () const
	Shade only front side of surface.
bool	shadeBackOnly () const
	Shade only front side of surface.
void	enableBothSidesMode ()
void	enableFrontSideMode ()
void	enableBackSideMode ()
bool	isPixel (int32_t px, int32_t py) const
bool	isPixelX (int32_t px) const
bool	isPixelY (int32_t py) const
float	w () const
	Current homogeneous W coordinate:
float	Z () const
	Current Z coordinate - W-normalized!
const fdk::Vec3f &	PW () const
fdk::Vec3f &	PW ()
const fdk::Vec3f &	PL () const
fdk::Vec3f &	PL ()
const fdk::Vec3f &	UV () const
fdk::Vec3f &	UV ()
const fdk::Vec3f &	N () const
fdk::Vec3f &	N ()
const fdk::Vec4f &	Cf () const
fdk::Vec4f &	Cf ()
const fdk::Vec4f &	rgba () const
fdk::Vec4f &	rgba ()
const fdk::Vec3f &	rgb () const
fdk::Vec3f &	rgb ()
float	r () const
float	g () const
float	b () const
float	a () const
float	opacity () const
void	sample (DD::Image::Sampler *sampler, DD::Image::Pixel &out) const
void	sample (DD::Image::Iop *texture, DD::Image::Pixel &out) const
	Slower version using a raw Iop.

Public Attributes
SlrVertex	v
	Current values for shader - W-normalized, volatile!
double	distance
	Distance from last intersection/camera.
SlrVertex	vP
	Current values for shader - in homogeneous-space!
SlrVertex	vdX
	Change if X of render pixel is increased by 1.
SlrVertex	vdY
	Change if Y of render pixel is increased by 1.
int32_t	x
int32_t	y
	Current output screen coords.
float	sx
float	sy
	Current output subpixel screen coords.
int32_t	si
	Current subsample index.
double	time
	Absolute frame time (i.e. 101.0, 155.0, etc)
double	shutter_offset
	Shutter offset from time0 reference (i.e. -0.5, -0.35, 0.0, +0.5, etc)
uint32_t	shutter_step
	Global-context shutter-step index for the context's time.
SlrRenderContext *	slrtx
	For global rendering params, render Op, etc.
SlrScene *	motion_scene0
	Scene info for motion sample at start of shutter_step.
SlrScene *	motion_scene1
	Scene info for motion sample at end of shutter_step.
SlrPrimInfo *	motion_priminfo0
	Current object SlrPrimInfo for motion sample at start of shutter_step.
SlrPrimInfo *	motion_priminfo1
	Current object SlrPrimInfo for motion sample at end of shutter_step.
const SlrShadingContext *	previous_stx
	Previous SlrShadingContext, normally the last surface intersected/shaded.
SlrThreadContext *	sttx
	Per-thread 'scratch-pad' vars to speed up Pixel usage in shaders.
SlrTriangle *	rtriangle
	Current render triangle being evaluated.
SlrSurfaceShader *	surface_shader
	Current surface shader being evaluated.
SlrGeometryShader *	displacement_shader
	Current displacement shader being evaluated, if any.
SlrLightShader *	light_shader
	Current light shader being evaluated, if any.
SlrVolumeShader *	atmosphere_shader
	Current atmospheric volume shader being evaluated, if any.
int32_t	sides_mode
	Which sides to intersect against and shade (use methods to query)
bool	texture_sampling
	Whether shaders should sample their textures.
DD::Image::TextureFilter *	texture_filter
	Global texture filter to use.
bool	lighting_enabled
	If true, even if no lights the surface shaders should do illum calcs.
fdk::Vec3f	ambient
	Global ambient setting.

Protected Attributes
SlrRayTestCache *	_ray_test_cache
	Triangle cache for intersection testing.

Detailed Description

This class is intended to be passed up a SlrShader tree. It's initialized with basic vertex info like the point location, a UV coordinate and a normal. A shader can then modify the parameters producing effects like point displacement, UV projection, and normal remapping.

Member Function Documentation

float slr::SlrShadingContext::getPolygonEdgeDistance	(	const fdk::Vec4f &	P,
		float	minDist
	)		const

Distance from point P to the nearest not occluded polygon edge in screen-space for the current primitive. All triangles generated from the tessellation of the original SlrPrimInfo are tested, so the method checks all polygon edges. Returns when the first edge distance is under minDist.

References slr::SlrTriangle::eMaskEdgeAll, slr::SlrTriangle::faceEdgeMask, slr::SlrTriangle::nextTri, slr::SlrVertex::P, rtriangle, slr::SlrTriangle::v, and w().

void slr::SlrShadingContext::sample	(	DD::Image::Sampler *	sampler,
		DD::Image::Pixel &	out
	)		const

Use the UV and the derivatives of UV to sample the incoming image. UV of 0,0 is mapped to the lower-left corner of the image's format, and 1,1 is mapped to the upper-right corner.

For texture sampling it's much faster to provide a DD::Image::Sampler rather than a raw Iop so Tile caching is properly leveraged.

References DD::Image::Box::h(), texture_filter, slr::SlrVertex::UV, vdX, vdY, vP, DD::Image::Box::w(), DD::Image::Box::x(), DD::Image::Box::y(), and y.