Documentation
¶
Overview ¶
Package lights provides implementations of the tracer.Light interface.
- general transform (either orthonormal or scales intensity)
Index ¶
- func DiskLight(brightness Color, diam float64, center Vec) Light
- func PointLight(power Color, pos Vec) Light
- func RectangleLight(brightness Color, w, h float64, center Vec) Light
- func SunLight(brightnessAtEarth Color, angularDiam float64, yaw, pitch float64) Light
- func Transformed(l Light, t *geom.AffineTransform) Light
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func PointLight ¶
func PointLight(power Color, pos Vec) Light
func RectangleLight ¶
func RectangleLight(brightness Color, w, h float64, center Vec) Light
func SunLight ¶
SunLight constructs a far-away circlular light source, like the sun. angularDiam is the angular diameter (in radians).
The angular diameter of the sun seem from the earth is about 0.53 degrees (https://en.wikipedia.org/wiki/Angular_diameter#Use_in_astronomy)
brightnessAtEarth is the brightness that a 100% reflective matte surface receives when perpendicular to the sunlight. A brightness of (1,1,1) is thus easy to understand: this is the highest brightness that is guaranteed not to overexpose any scene.
yaw is the horizontal angle with respect to the -z axis. Thus 0 degree yaw means the sun is in the north.
pitch is the vertical angle above the horizon. 90 degree pitch means the sun is in the zenith.
func Transformed ¶
func Transformed(l Light, t *geom.AffineTransform) Light
Transformed returns a transformed instance of the original light. The transform may be a rotation and/or scale (equal in all directions), but not an anistropic scale or shear, etc.
Multiple transformed instances of the same object may be made, they efficiently share underlying state.
TODO: if object is already an instance of *transformed, combine both transforms into one.
TODO: arguments: first transform, then object
Types ¶
This section is empty.
Source Files