HyperQuark
Compile scratch projects to WASM
Prerequisites
- Rust (v1.65.0 or later)
- the
wasm32-unknown-unknowntarget (rustup target add wasm32-unknown-unknown) - wasm-bindgen-cli (
cargo install -f wasm-bindgen-cli) - wasm-opt (install binaryen using whatever package manager you use)
Building
./build.sh -pVW # use -dVW for a debug build without optimisationYou may need to run chmod +x build.sh if it says it doesn't have permission.
The build script has additonal configuration options; run ./build.sh -h for info on these.
If you experience runtime stack overflow errors in debug mode, try using the -O option to enable wasm-opt.
generared WASM module memory layout
| name | number of bytes | optional? | description | |
|---|---|---|---|---|
| redraw_requested | 4 | no | if a redraw has been requested or not | |
| thread_num | 4 | no | the number of currently running threads | |
| vars | 16 * number of global & local variables | yes | see variables | |
| sprite_info | 80 * number of sprites (i.e. target num - 1) |
yes | see sprite info | |
| threads | 4 * thread_num | no | imdices of the next step funcs of currently running threads | |
| <!-- | pen | 360 * 480 * 4 = 691200 | yes | present if pen is used; the pen layer: 4 bytes for each rgba pixel, from left to right, top to bottom |
| spriteData | 43(?) * number of sprites | yes | for each sprite (not target), 4 bytes each (1 f32 each) for: x, y, size, direction, costume number, pitch, pan,layer number; plus 1 byte each for: colour effect, ghost effect, mosaic effect, whirl effect, pixelate effect, fisheye effect, brightness effect, volume, visibility, rotation style, draggable | |
| stageData | 8 | no | 4 bytes each for: backdrop number; plus 1 byte each for: volume, video state, tempo, video transparency | |
| cloneData | 43(?) * 300 = 12900 | yes | if a create clone of () block is present, same as above, but for each clone. |
-->
Sprite info
| byte | type | name | description | ||
|---|---|---|---|---|---|
| 0-7 | f64 | x | x pos | ||
| 8-15 | f64 | y | y pos | ||
| 16-19 | f32 | pen_color | hue of pen (0-100) | ||
| 20-23 | f32 | pen_saturation | saturation of pen (0-100) | ||
| 24-27 | f32 | pen_brightness | value of pen (0-100) | ||
| 28-31 | f32 | pen_transparency | transparency of pen (0-100) | ||
| 32-47 | f32(x4) | pen_color4f | rgba color of pen [(0-1)x4] | ||
| 48-55 | f64 | pen_size | pen radius | ||
| 56 | i8 | pen_down | 1 if pen down else 0 |
||
| 57 | i8 | visible | 1 if sprite is visible else 0 |
||
| 58-59 | - | padding | reserved | ||
| 60-63 | i32 | costume | the current costume number, 0-indexed | ||
| 64-71 | f64 | size | sprite size | ||
| 72-79 | f64 | rotation | sprite rotation, in scratch angles (0 = up, 90 = right) | ||
| <!-- | 56-57 | ? | padding | padding | --> |
Variables
| byte | description |
|---|---|
| 0-3 | identifies the type of the variable |
| 4-7 | padding |
| 8-15 | identifies the value of the variable |
Variable types
| value | type | variable value type | value description |
|---|---|---|---|
| 0x00 | float64 | f64 |
a float |
| 0x01 | bool64 | i64 |
an integer - only the least significant bit is used |
| 0x02 | externref string (64 bit) | i64 |
wrapped to a 32 bit pointer to an externref value in the anyref table |
| 0x03 | int64 | i64 |
a 64-bit integer |
Memory layout guarantees
All values should be guaranteed to have the maximum possible alignment for that value type. Unused/padding bytes are not guaranteed to have any specific values and may be overwritten.
License
Licensed under either of
- Apache License, Version 2.0 (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
- MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)
at your option.
Contribution
Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, as defined in the Apache-2.0 license, shall be dual licensed as above, without any additional terms or conditions.