Optimized rastering
This release brings great strides in rastering performance, especially for very large, sparse rasters.
- Switched to a proper fixed-point dithering implementation from the twelve monkeys image library.
- Implemented more detailed SVG output, where CSS classes are used to indicate different kinds of paths, see the embedded stylesheet in the output SVG for details:
- move: green, thin
- cut: black, thick
- engraving with the laser on: dark blue, thick
- engraving with the laser off: red, half-thick
- engraving acceleration: yellow, half-thick
- Implemented two new rastering modes, selectable via the photonsaw-raster-optimization style parameter:
- none: The old rastering mode, each line of a raster is scanned at the raster-speed from the first pixel to the last.
- fast: Sufficiently long blank spaces in each line is traversed at max speed in stead of the raster-speed.
- fastest: Lines are split into sections which allow distant parts of the image to be rastered individually.
Benchmarks for some different SVGs:
| SVG | NONE | FAST | FASTEST |
|---|---|---|---|
| frandsen.svg, low-res | 337 s | 318 s | 302 s |
| frandsen.svg, high-res | 1060 s | 995 s | 901 s |
| flemming,svg, high-res | 3191 s | 2566 s | 2005 s |
| flemming,svg, low-res | 1000 s | 808 s | 707 s |
The larger the raster and the more sparse it is, the more advantage there is to the optimization.
See the tool paths in the optimization-data.zip