update documentation

README.org

@@ -51,14 +51,12 @@
 * Technical Details
 
 ** VM Architecture
-   - Von Neumann style bytecode interpreter written in C89.
+   - register based bytecode interpreter written in C89.
    - Portable to new systems, microcontrollers, and web via Emscripten.
 
 ** Memory Management
    - Reference counting for globally scoped objects.
    - =weak= keyword to avoid cyclical references.
-   - garbage collection as a system call (choose when to free memory)
-   - Arena allocators for short-lived, scoped memory (e.g., function-local objects).
 
 ** Rendering & I/O
    - SDL2-based abstraction for input, audio, and rendering.

docs/MACHINE.org

@@ -14,7 +14,7 @@ one large uint32 array
 :PROPERTIES:
 :CUSTOM-ID: types
 :END:
-real (fixed point numbers)| Q16.16 number
+real (floating point number) f32
 int (integer) i32
 nat (unsigned integer) u32
 

docs/SPECIFICATION.org

@@ -52,9 +52,7 @@ type Vec3 {
 :CUSTOM_ID: numeric
 :END:
 - =real=
-  - 32 bit Q16.16 fixed point by default.
-  - self casts to a 64 bit floating point (Double) by default for modern CPUs that have a FPU
-    for 3D math for performance reasons
+  - 32 bit floats
 - =int=
   - 32 bit integer
 - =nat=

src/main.c

@@ -16,13 +16,10 @@
 #include <emscripten.h>
 #endif
 
-uint32_t pc = 1; /* Program counter */
-
 Code *code;
 
 void mainloop() {
-  pc = step_vm(&code->current, code->memory);
-  if (pc == 0) {
+  if (!step_vm(&code->current, code->memory)) {
 #ifdef __EMSCRIPTEN__
     emscripten_cancel_main_loop(); /* this should "kill" the app. */
 #else