After a break from CodeLab read this cheat sheet first to refresh your memory.
Run the container with web server and compiler:
$ docker compose up -dRun the monitor script to automatically compile on changes:
$ cd bash && sh monitor.shCreate 3D engine using WebAssembly and WebGPU without libraries.
- GLTF loader
A single bit uses the base-2 number system, which means that each hexadecimal digit directly corresponds to a 4-bit binary number. You need only two digits to represent one byte in hexadecimal format.
0x is a common prefix used in programming and computing to denote that the number that follows is in hexadecimal format.
Hexadecimal is a base-16 number system, which means each position in a hexadecimal number represents a power of 16, much like in base-10 number system each position in a decimal number represents a power of 10.
In the hexadecimal format, the digits 0-9 represent values zero to nine, and the letters A-F represent values ten to fifteen.
We are not using the C++ standard library, so we have to create even the most basic tools ourselves, including a memory management (similar to malloc and free), string manipulation, dynamic array support, and math functions.
The framework which include subprojects to compile C++ to WebAssembly.
https://lld.llvm.org/WebAssembly.html
HEAP, depending on the context, is either a data structure or a memory region; the latter refers to the context of memory in the WebAssembly module.
Address is a simple numeric value that indicates a particular byte in a memory.
Pointer is a variable that stores the address of another variable which is used to access and manipulate data stored in memory.
Page in WebAssembly memory is a 64 KiB (65 536 bytes) block of memory. The memory size is determined by amount of the pages.
When writing multi-byte data to memory the byte order is little endian which means that the least significant byte is stored at the lowest memory address, and the most significant byte at the highest.
// Represent values from 0 to 4294967295 (32-bit)
unsigned int getAddress(){
int myVariable = 10;
// Create a pointer to myVariable using &
int* myPointer = &myVariable;
// Write to myVariable through the pointer with *
*myPointer = 20;
// Get the address of the pointer
unsigned int address = reinterpret_cast<unsigned int>(myPointer);
// Address that contains the written value of 20
return address;
}The value of __heap_base is fixed at compile/link time and does not change during the execution of your program.
$ google-chrome-unstable --enable-features=VulkanWebGPU Shading Language (WGSL) is the shader language for the WebGPU API.
The transformation matrix calculation maps the 3D points (x, y and z) in a scene onto a 2D plane (x and y). There are two main types of projection used in this transformation, namely orthographic and perspective.
Orthographic projection discards the z-axis and preserves the dimensions of objects, meaning objects retain the same size regardless of their distance from the view plane.
Perspective projection uses all axes to simulate how the human eye sees. Objects farther from the viewer appear smaller, thereby giving a sense of depth.