A simple renderer (rasterization-based) written in Go.
The OG tinyrenderer project helped me alot. It's amazing stuff, and I highly recommend everyone check it out.
The code is pretty self-contained. I only used a 3rd-party library imaging to flip images vertically.
To do your custom render:
go run render.go <path to .obj file> <path to texture file>
For example, see run.sh:
go run data/obj/bunny_2.obj data/textures/bunny_texture.jpg
Of course, you can first build render.go, and then run the executable:
go build render.go
./render <path to .obj file> <path to texture file>
You could also play with some other parameters (light direction, camera position, spectral lighting, and etc) in render.go.
eye: The camera position. Default is (0, 0, 1).center: Position the camera is looking at Default is (0, 0, 0).up: The vertical axis of the camera. Default is (0, 1, 0), which is the y-axis.lightDir: Light ray direction. Default is (0, 0, -1), which means the light is parellel to user's eye.specCoeff: Weight of spectral lighting. (For the shiny dragon above, I used 20.0)imageHeight: Pixel height of output image.background: Whether to color output image background black. If not, then output image has transparent background.outFile: Render output file path.defaultFill: If no texture is specified, use this color.
Basics
| Wireframe | Triangle rasterization |
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Shading
| Flat shading | Gouraud shading | Phong shading |
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Perspective
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Textures
Kudos to the author of this article for providing custom Stanford bunny texture files.
| Colored | Terracotta |
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Camera
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Light
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Specular lighting
The stronger specular lighting is, the more "glossy" the object surface becomes. I simply used uniform power for each pixel since specular intensity is not specified in my texture files.
| No specular | Some specular (used) | Intense specular |
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