This work implements an N-dimensional version of Peter Shirley's, Trevor David Black's, and Steve Hollasch's raytracer from their Raytracing in One Weekend Book Series.
This implementation outputs PNG files rather than PPM files. Additionally, it supports outputting (N-1)-dimensional image cubes and interleaving the various slices with borders between them.
You can output an image akin to Book 1, Chapter 2, Section 2's image with the following function:
(weekend-raytracer/examples:b1c2-2image &optional verticalp)
The image here is a 3-D image cube rendered as horizontal slices of
constant blueness (or as vertical slices of constant blueness if
VERTICALP is non-NIL). The first slice is identical to the
book image.
The book image here renders an interpolation between blue and white. This image renders between blue and white but also between orange and the color the book would render.
You can output an image akin to Book 1, Chapter 4, Section 2's image with the following function:
(weekend-raytracer/examples:b1c4-2image &optional verticalp)
The image here is a 3-D image cube rendered as horizontal slices. The color of each pixel is based on the 3rd and 4th coordinates of the camera ray's direction.
The book image here renders an interpolation between blue and white with a red sphere in the center of the view.
The book has the image plane in the negative-z direction and then uses x and y for coordinates within the image square.
For maximum utility when changing number of dimensions, this code puts the image plane in the negative-x direction and then uses y, z, and w to move around the image cube.
I have moved the sphere slightly in the w direction.
You can output an image akin to Book 1, Chapter 5, Section 2's image with the following function:
(weekend-raytracer/examples:b1c5-2image &optional verticalp)
The image here is a 3-D image cube rendered as horizontal slices. The color of each pixel is based on the 3rd and 4th coordinates of the camera ray's direction except where the ray intersects the sphere. Where the ray intersects the sphere, the image is solid red.
The book image here renders an interpolation between blue and white with a sphere in the center of the view. The colors on the sphere are a function of the normal on the sphere at the point of intersection.
The book has the image plane in the negative-z direction and then uses x and y for coordinates within the image square.
For maximum utility when changing number of dimensions, this code puts the image plane in the negative-x direction and then uses y, z, and w to move around the image cube.
I have moved the sphere slightly in the w direction.
You can output an image akin to Book 1, Chapter 6, Section 1's image with the following function:
(weekend-raytracer/examples:b1c6-1image &optional verticalp)
The image here is a 3-D image cube rendered as horizontal slices. The color of each pixel is based on the 3rd and 4th coordinates of the camera ray's direction except where the ray intersects the sphere. Where the ray intersects the sphere, the color is
r = (/ (1+ (vref normal 1)) 2)
g = (/ (1+ (vref normal 2)) 2)
b = (/ (1+ (vref normal 0)) 2)
The book image here renders an interpolation between blue and white with a sphere in the center of the view and another sphere as the ground. The colors on the sphere are a function of the normal on the sphere at the point of intersection.
The book has the image plane in the negative-z direction and then uses x and y for coordinates within the image square.
For maximum utility when changing number of dimensions, this code puts the image plane in the negative-x direction and then uses y, z, and w to move around the image cube.
I have moved both spheres slightly in the w direction.
You can output an image akin to Book 1, Chapter 6, Section 7's image with the following function:
(weekend-raytracer/examples:b1c6-7image &optional verticalp)
The image here is a 3-D image cube rendered as horizontal slices. The color of each pixel is based on the 3rd and 4th coordinates of the camera ray's direction except where the ray intersects the sphere. Where the ray intersects the spheres, the color is
r = (/ (1+ (vref normal 1)) 2)
g = (/ (1+ (vref normal 2)) 2)
b = (/ (1+ (vref normal 0)) 2)
This is essentially the same as image 1.6.7 above. The difference here is that the camera is moved into its own class. The sky color is also not being LERP-ed at the moment as a function of the normal to simplify allowing the camera to take in arbitrary numbers of spatial and color dimensions.
You can generate this image with the following function:
(weekend-raytracer/examples:b1c7-1image &optional verticalp)
The image here is a 3-D image cube rendered as horizontal slices. The color of each pixel is the default sky color except where the ray intersects the sphere. Where the ray intersects the spheres, the color is
r = (/ (1+ (vref normal 1)) 2)
g = (/ (1+ (vref normal 2)) 2)
b = (/ (1+ (vref normal 0)) 2)
This is essentially the same as image 1.7.1 above except with anti-aliasing.
You can generate this image with the following function:
(weekend-raytracer/examples:b1c8-2image samples-per-pixel &optional verticalp)
The current anti-aliasing takes the aspect ratios into consideration when deciding how far to stray from the center ray of a pixel. Without this, the fact that some axises have hundreds of pixels along them and others only have a few pixels along them means that pixel cubes are really-long along some axises making it a great deal easier to hit or miss objects in some directions. That results in very fuzzy edges unless you bump the number of samples up by many orders of magnitude.
This means the simulated camera has roughly (hyper)cubical sensors at each pixel but that the pixels are spaced out more on axises where there are fewer pixels per degree of view.