@@ -220,7 +220,8 @@ It's reasonable to think of supersampled rendering as rendering an image that is
...
@@ -220,7 +220,8 @@ It's reasonable to think of supersampled rendering as rendering an image that is
To help you out, here is a sketch of an implementation:
To help you out, here is a sketch of an implementation:
- The image being rendered is stored in `render_target`, an array that stores each pixel's color components as an `uint8_t` in rgbargba... order. The width and height in pixels of the `render_target` are stored as `target_w` and `target_h` respectively. Refer to `rasterize_point` to see how it can be modified.
- The image being rendered is stored in `render_target`, an array that stores each pixel's color components as an `uint8_t` in rgbargba... order. The width and height in pixels of the `render_target` are stored as `target_w` and `target_h` respectively. Refer to `rasterize_point` to see how it can be modified.
- When rasterizing primitives such as triangles, rather than directly updating `render_target`, your rasterization should update the contents of a larger buffer (perhaps call it `sample_buffer` or `supersample_target`) that holds the per-super-sample results. It's up to you to manage this buffer yourself. (Hint: See `software_renderer.h` for a declarations of helpers used by the reference. The functions `vector::resize()` and `memset()` may be worth looking into.)
- When rasterizing primitives such as triangles, rather than directly updating `render_target`, your rasterization should update the contents of a larger buffer (perhaps call it `sample_buffer` or `supersample_target`) that holds the per-super-sample results. It's up to you to manage this buffer yourself. (Hint: See `software_renderer.h` for declarations of helpers used by the reference. The functions `vector::resize()` and `memset()` may be worth looking into.)
- **Don't** add your sample buffer as a member of `SoftwareRenderer`: instead add it to `SoftwareRendererImp`. This is because the pre-compiled reference code relies on the current memory layout of `SoftwareRenderer`.
- After rendering is complete, your implementation must resample the supersampled results buffer to obtain sample values for the render target. This is often called "resolving" the supersample buffer into the render target. Please implement resampling using a simple [unit-area box filter](https://en.wikipedia.org/wiki/Box_blur).
- After rendering is complete, your implementation must resample the supersampled results buffer to obtain sample values for the render target. This is often called "resolving" the supersample buffer into the render target. Please implement resampling using a simple [unit-area box filter](https://en.wikipedia.org/wiki/Box_blur).
- Note that the function `SoftwareRendererImp::resolve()` is called by `draw_svg()` after the SVG file has been drawn. Thus it's a very convenient place to perform resampling.
- Note that the function `SoftwareRendererImp::resolve()` is called by `draw_svg()` after the SVG file has been drawn. Thus it's a very convenient place to perform resampling.
