fill out box2d methods

examples/box2d_demo/config.js

@@ -0,0 +1,8 @@
+var config = {
+  title: "Box2D Physics Demo",
+  width: 1280,
+  height: 720,
+  fullscreen: false
+}
+
+return config

examples/box2d_demo/main.js

@@ -0,0 +1,343 @@
+var box2d = use('box2d')
+var moth = use('moth', $_.delay)
+moth.initialize()
+var draw2d = use('draw2d')
+
+// Physics world setup
+var world = new box2d.World({
+  gravity: {x: 0, y: -10}
+})
+
+// Ground body (static)
+var ground = world.createBody({
+  type: 'static',
+  position: {x: 0, y: -10}
+})
+
+var groundShape = ground.createBoxShape({
+  width: 50,
+  height: 0.5,
+  density: 0,
+  friction: 0.7
+})
+
+// Walls
+var leftWall = world.createBody({
+  type: 'static',
+  position: {x: -25, y: 0}
+})
+leftWall.createBoxShape({
+  width: 0.5,
+  height: 30,
+  density: 0
+})
+
+var rightWall = world.createBody({
+  type: 'static',
+  position: {x: 25, y: 0}
+})
+rightWall.createBoxShape({
+  width: 0.5,
+  height: 30,
+  density: 0
+})
+
+// Dynamic bodies array
+var boxes = []
+var circles = []
+
+// Create some dynamic boxes
+for (var i = 0; i < 5; i++) {
+  var box = world.createBody({
+    type: 'dynamic',
+    position: {x: -10 + i * 4, y: 5 + i * 3},
+    angle: Math.random() * Math.PI
+  })
+  
+  box.createBoxShape({
+    width: 2,
+    height: 2,
+    density: 1.0,
+    friction: 0.3,
+    restitution: 0.5
+  })
+  
+  boxes.push(box)
+}
+
+// Create some circles
+for (var i = 0; i < 3; i++) {
+  var circle = world.createBody({
+    type: 'dynamic',
+    position: {x: 5 + i * 3, y: 10 + i * 2}
+  })
+  
+  circle.createCircleShape({
+    radius: 1,
+    density: 0.5,
+    friction: 0.2,
+    restitution: 0.8
+  })
+  
+  circles.push(circle)
+}
+
+// Connected bodies with distance joint
+var bodyA = world.createBody({
+  type: 'dynamic',
+  position: {x: -5, y: 15}
+})
+bodyA.createCircleShape({
+  radius: 0.5,
+  density: 1.0
+})
+
+var bodyB = world.createBody({
+  type: 'dynamic',
+  position: {x: 0, y: 15}
+})
+bodyB.createCircleShape({
+  radius: 0.5,
+  density: 1.0
+})
+
+var joint = world.createDistanceJoint({
+  bodyA: bodyA,
+  bodyB: bodyB,
+  localAnchorA: {x: 0, y: 0},
+  localAnchorB: {x: 0, y: 0},
+  length: 5
+})
+
+// Mouse interaction
+var mouseBody = null
+var mousePressed = false
+
+// Game state
+var camera = {x: 0, y: 0, zoom: 10}
+
+// Input state
+var keys = {}
+var mouse = {
+  pos: {x: 0, y: 0},
+  buttons: [false, false, false]
+}
+
+// Main update function
+prosperon.on('update', function(dt) {
+  // Step physics simulation
+  world.step(dt, 4)
+  
+  // Camera controls
+  if (keys[4]) camera.x -= 20 * dt  // A
+  if (keys[7]) camera.x += 20 * dt  // D
+  if (keys[26]) camera.y += 20 * dt // W
+  if (keys[22]) camera.y -= 20 * dt // S
+  if (keys[20]) camera.zoom *= 1 + dt // Q
+  if (keys[8]) camera.zoom *= 1 - dt  // E
+  
+  // Mouse interaction
+  var mouseWorld = screenToWorld(mouse.pos)
+    // Raycast to find body under mouse
+    var result = world.rayCast(mouseWorld, {x: 0, y: -1}, 0.1)
+    
+    if (!result.hit) {
+      // Create new body at mouse position
+      if (keys[225]) { // LSHIFT
+        // Create circle
+        var newCircle = world.createBody({
+          type: 'dynamic',
+          position: mouseWorld
+        })
+        newCircle.createCircleShape({
+          radius: 0.5 + Math.random(),
+          density: 1.0,
+          restitution: 0.3 + Math.random() * 0.5
+        })
+        circles.push(newCircle)
+      } else {
+        // Create box
+        var newBox = world.createBody({
+          type: 'dynamic',
+          position: mouseWorld,
+          angle: Math.random() * Math.PI * 2
+        })
+        newBox.createBoxShape({
+          width: 1 + Math.random() * 2,
+          height: 1 + Math.random() * 2,
+          density: 1.0,
+          restitution: 0.2 + Math.random() * 0.3
+        })
+        boxes.push(newBox)
+      }
+    }
+  
+    boxes.forEach(function(box) {
+      var dir = {
+        x: box.position.x - mouseWorld.x,
+        y: box.position.y - mouseWorld.y
+      }
+      var dist = Math.sqrt(dir.x * dir.x + dir.y * dir.y)
+      if (dist < 10 && dist > 0.1) {
+        dir.x /= dist
+        dir.y /= dist
+        box.applyLinearImpulse({x: dir.x * 50, y: dir.y * 50})
+      }
+    })
+
+  
+  // Reset with R
+  if (keys[21] && !keys[21 + '_prev']) { // R key pressed
+    // Reset all dynamic bodies
+    boxes.forEach(function(box) {
+      box.position = {x: Math.random() * 20 - 10, y: 10 + Math.random() * 10}
+      box.angle = Math.random() * Math.PI * 2
+      box.linearVelocity = {x: 0, y: 0}
+      box.angularVelocity = 0
+    })
+    
+    circles.forEach(function(circle) {
+      circle.position = {x: Math.random() * 20 - 10, y: 10 + Math.random() * 10}
+      circle.linearVelocity = {x: 0, y: 0}
+    })
+  }
+  
+  // Update previous key states
+  for (var k in keys) {
+    if (k.indexOf('_prev') === -1) {
+      keys[k + '_prev'] = keys[k]
+    }
+  }
+})
+
+// Event handlers
+prosperon.on('key_down', function(e) {
+  keys[e.scancode] = true
+})
+
+prosperon.on('key_up', function(e) {
+  keys[e.scancode] = false
+})
+
+prosperon.on('mouse_button_down', function(e) {
+  mouse.buttons[e.which] = true
+  
+  if (e.which === 0 && !mousePressed) {
+    mousePressed = true
+    var mouseWorld = screenToWorld(mouse.pos)
+    
+    // Raycast to find body under mouse
+    var result = world.rayCast(mouseWorld, {x: 0, y: -1}, 0.1)
+    
+    if (!result.hit) {
+      // Create new body at mouse position
+      if (keys[225]) { // LSHIFT
+        // Create circle
+        var newCircle = world.createBody({
+          type: 'dynamic',
+          position: mouseWorld
+        })
+        newCircle.createCircleShape({
+          radius: 0.5 + Math.random(),
+          density: 1.0,
+          restitution: 0.3 + Math.random() * 0.5
+        })
+        circles.push(newCircle)
+      } else {
+        // Create box
+        var newBox = world.createBody({
+          type: 'dynamic',
+          position: mouseWorld,
+          angle: Math.random() * Math.PI * 2
+        })
+        newBox.createBoxShape({
+          width: 1 + Math.random() * 2,
+          height: 1 + Math.random() * 2,
+          density: 1.0,
+          restitution: 0.2 + Math.random() * 0.3
+        })
+        boxes.push(newBox)
+      }
+    }
+  }
+  
+  if (e.which === 1) {
+    // Apply impulse with right click
+    var mouseWorld = screenToWorld(mouse.pos)
+    boxes.forEach(function(box) {
+      var dir = {
+        x: box.position.x - mouseWorld.x,
+        y: box.position.y - mouseWorld.y
+      }
+      var dist = Math.sqrt(dir.x * dir.x + dir.y * dir.y)
+      if (dist < 10 && dist > 0.1) {
+        dir.x /= dist
+        dir.y /= dist
+        box.applyLinearImpulse({x: dir.x * 50, y: dir.y * 50})
+      }
+    })
+  }
+})
+
+prosperon.on('mouse_button_up', function(e) {
+  mouse.buttons[e.which] = false
+  if (e.which === 0) {
+    mousePressed = false
+  }
+})
+
+prosperon.on('mouse_motion', function(e) {
+  mouse.pos = e.pos
+})
+
+// Rendering
+prosperon.on('draw', function() {
+  // Clear background
+  
+  // Draw ground
+  drawBox(ground.position, 50, 0.5, ground.angle, {r: 0.5, g: 0.5, b: 0.5, a: 1})
+  
+  // Draw walls
+  drawBox(leftWall.position, 0.5, 30, 0, {r: 0.5, g: 0.5, b: 0.5, a: 1})
+  drawBox(rightWall.position, 0.5, 30, 0, {r: 0.5, g: 0.5, b: 0.5, a: 1})
+  
+  // Draw boxes
+  boxes.forEach(function(box) {
+    drawBox(box.position, 2, 2, box.angle, {r: 0.8, g: 0.3, b: 0.3, a: 1})
+  })
+  
+  // Draw circles
+  circles.forEach(function(circle) {
+    draw2d.circle(circle.position, 1, {r: 0.3, g: 0.8, b: 0.3, a: 1})
+  })
+  
+  // Draw connected bodies
+  draw2d.circle(bodyA.position, 0.5, {r: 0.8, g: 0.8, b: 0.3, a: 1})
+  draw2d.circle(bodyB.position, 0.5, {r: 0.8, g: 0.8, b: 0.3, a: 1})
+  draw2d.line([bodyA.position, bodyB.position], {r: 1, g: 1, b: 0, a: 0.5})
+  
+  // Draw UI
+  draw2d.text("Box2D Demo", {x: 10, y: 10}, 20, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("Controls:", {x: 10, y: 40}, 16, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("- WASD: Move camera", {x: 10, y: 60}, 14, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("- Q/E: Zoom in/out", {x: 10, y: 80}, 14, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("- Left click: Create box", {x: 10, y: 100}, 14, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("- Shift + Left click: Create circle", {x: 10, y: 120}, 14, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("- Right click: Apply impulse", {x: 10, y: 140}, 14, {r: 1, g: 1, b: 1, a: 1})
+  draw2d.text("- R: Reset bodies", {x: 10, y: 160}, 14, {r: 1, g: 1, b: 1, a: 1})
+  
+  // Show physics stats
+  draw2d.text("Bodies: " + (boxes.length + circles.length + 4), {x: 10, y: 200}, 14, {r: 1, g: 1, b: 1, a: 1})
+})
+
+// Helper functions
+function drawBox(pos, width, height, angle, color) {
+  draw2d.rectangle({x:pos.x,y:pos.y,width, height})
+}
+
+function screenToWorld(screenPos) {
+  return {
+    x: (screenPos.x - prosperon.x * 0.5) / camera.zoom + camera.x,
+    y: (screenPos.y - prosperon.y * 0.5) / camera.zoom + camera.y
+  }
+}

meson.build

@@ -94,6 +94,18 @@ sdl3_opts.add_cmake_defines({
   'SDL_PULSEAUDIO': 'ON',
 })
 
+box2d_opts = cmake.subproject_options()
+box2d_opts.add_cmake_defines({
+  'BOX2D_SAMPLES': 'OFF',
+  'BOX2D_BUILD_STATIC': 'ON',
+  'BOX2d_AVX2': 'ON',
+  'BOX2D_BUILD_SHARED': 'OFF',
+  'CMAKE_BUILD_TYPE': 'Release',
+})
+
+box2d_proj = cmake.subproject('box2d', options: box2d_opts)
+deps += box2d_proj.dependency('box2d')
+
 cc = meson.get_compiler('c')
 
 if host_machine.system() == 'darwin'
@@ -142,7 +154,6 @@ deps += dependency('qjs-layout', static:true)
 deps += dependency('qjs-miniz', static:true)
 deps += dependency('physfs', static:true)
 deps += dependency('threads')
-deps += dependency('chipmunk', static:true)
 
 if host_machine.system() != 'emscripten'
   deps += dependency('enet', static:true)
@@ -192,12 +203,14 @@ endif
 
 link_args = link
 sources = []
+
 src += [
   'anim.c', 'config.c', 'datastream.c','font.c','HandmadeMath.c','jsffi.c','model.c',
   'render.c','simplex.c','spline.c', 'transform.c','prosperon.c',  'wildmatch.c',
   'sprite.c', 'rtree.c', 'qjs_nota.c', 'qjs_soloud.c', 'qjs_sdl.c', 'qjs_math.c', 'qjs_geometry.c', 'qjs_transform.c', 'qjs_sprite.c', 'qjs_io.c', 'qjs_os.c', 'qjs_actor.c',
   'qjs_qr.c', 'qjs_wota.c', 'monocypher.c', 'qjs_blob.c', 'qjs_crypto.c', 'qjs_time.c', 'qjs_http.c', 'qjs_rtree.c', 'qjs_spline.c', 'qjs_js.c', 'qjs_debug.c'
 ]
+src += 'qjs_box2d.c'
 # quirc src
 src += [
   'thirdparty/quirc/quirc.c', 'thirdparty/quirc/decode.c',

source/HandmadeMath.c

@@ -1,5 +1,7 @@
 #include "HandmadeMath.h"
 
+#include <stdlib.h>
+
 const HMM_Vec2 v2zero = {0,0};
 const HMM_Vec2 v2one = {1,1};
 const HMM_Vec3 v3zero = {0,0,0};

source/HandmadeMath.h

@@ -96,8 +96,6 @@
 #ifndef HANDMADE_MATH_H
 #define HANDMADE_MATH_H
 
-#include <chipmunk/chipmunk.h>
-
 #if !defined(HANDMADE_MATH_NO_SIMD)
   #if defined(__ARM_NEON) || defined(__ARM_NEON__)
     #define HANDMADE_MATH__USE_NEON 1
@@ -272,12 +270,6 @@ typedef union HMM_Vec3 {
     HMM_Vec2 VW;
   };
 
-  struct
-  {
-    HMM_Vec2 cp;
-    float _Ignored5;
-  };
-
   float Elements[3];
   float e[3];
 
@@ -373,12 +365,6 @@ typedef union HMM_Vec4 {
     HMM_Vec2 ZW;
   };
   
-  struct
-  {
-    HMM_Vec2 cp;
-    HMM_Vec2 wh;
-  };
-  
   HMM_Quat quat;
   struct {float x, y, z, w; };
   struct {float r, g, b, a; };

source/jsffi.c

@@ -32,6 +32,7 @@
 #include "qjs_dmon.h"
 #include "qjs_nota.h"
 #include "qjs_wota.h"
+#include "qjs_box2d.h"
 #include "qjs_enet.h"
 #include "qjs_soloud.h"
 #include "qjs_qr.h"
@@ -48,6 +49,7 @@
 #include "qjs_spline.h"
 #include "qjs_js.h"
 #include "qjs_debug.h"
+#include "qjs_box2d.h"
 #ifndef NSTEAM
 #include "qjs_steam.h"
 #endif
@@ -2895,6 +2897,7 @@ void ffi_load(JSContext *js)
   arrput(rt->module_registry, MISTLINE(enet));
   arrput(rt->module_registry, MISTLINE(qr));
   arrput(rt->module_registry, MISTLINE(wota));
+  arrput(rt->module_registry, MISTLINE(box2d));
   arrput(rt->module_registry, MISTLINE(crypto));
   arrput(rt->module_registry, MISTLINE(blob));
   arrput(rt->module_registry, MISTLINE(http));
@@ -2903,6 +2906,7 @@ void ffi_load(JSContext *js)
   arrput(rt->module_registry, MISTLINE(rtree));
   arrput(rt->module_registry, MISTLINE(sprite));
   arrput(rt->module_registry, MISTLINE(transform));
+  arrput(rt->module_registry, MISTLINE(box2d));
 
 #ifdef TRACY_ENABLE
   arrput(rt->module_registry, MISTLINE(tracy));

source/qjs_box2d.h

@@ -0,0 +1,8 @@
+#ifndef QJS_BOX2D_H
+#define QJS_BOX2D_H
+
+#include "quickjs.h"
+
+JSValue js_box2d_use(JSContext*);
+
+#endif

source/spline.c

@@ -2,6 +2,7 @@
 #include "stb_ds.h"
 #include "transform.h"
 #include "math.h"
+#include "float.h"
 
 /* -------------------------------------------------------------------------
    Cubic Spline Basis Matrices

source/sprite.c

@@ -1,5 +1,7 @@
 #include "sprite.h"
 
+#include <stdlib.h>
+
 sprite *make_sprite(void)
 {
   sprite *sprite = calloc(sizeof(*sprite),1);

subprojects/box2d.wrap

@@ -0,0 +1,4 @@
+[wrap-git]
+directory=box2d
+url=https://github.com/erincatto/box2d.git
+revision=v3.0.0

tests/box2d.js

@@ -0,0 +1,90 @@
+var box2d = use('box2d')
+
+// Create world with constructor
+var world = new box2d.World({gravity: {x: 0, y: -9.8}})
+console.log("Initial gravity:", world.gravity)
+
+// Create a dynamic body
+var body = world.createBody({
+  type: 'dynamic',
+  position: {x: 0, y: 10}
+})
+
+// Add a box shape to the body
+var shape = body.createBoxShape({
+  width: 1,
+  height: 1,
+  density: 1.0,
+  friction: 0.3,
+  restitution: 0.5
+})
+
+console.log("Initial position:", body.position)
+console.log("Initial velocity:", body.linearVelocity)
+
+// Simulate
+world.step(1/60, 4);
+console.log("After 1 step:", body.position)
+
+world.step(1/60, 4);
+console.log("After 2 steps:", body.position)
+
+world.step(1/60, 4);
+console.log("After 3 steps:", body.position)
+
+// Test applying forces
+body.applyForce({x: 100, y: 0})
+world.step(1/60, 4);
+console.log("After force:", body.position, "velocity:", body.linearVelocity)
+
+// Test properties
+console.log("Body type:", body.type)
+console.log("Body mass:", body.getMass())
+console.log("Body angle:", body.angle)
+
+// Test string body types
+var staticBody = world.createBody({
+  type: 'static',
+  position: {x: 0, y: 0}
+})
+console.log("Static body type:", staticBody.type)
+
+// Test ray casting
+var rayResult = world.rayCast({x: -5, y: 10}, {x: 10, y: 0}, 1.0)
+console.log("Ray cast result:", rayResult)
+
+// Test distance joint
+var bodyA = world.createBody({
+  type: 'dynamic',
+  position: {x: -2, y: 5}
+})
+bodyA.createCircleShape({
+  radius: 0.5,
+  density: 1.0
+})
+
+var bodyB = world.createBody({
+  type: 'dynamic',
+  position: {x: 2, y: 5}
+})
+bodyB.createCircleShape({
+  radius: 0.5,
+  density: 1.0
+})
+
+var joint = world.createDistanceJoint({
+  bodyA: bodyA,
+  bodyB: bodyB,
+  localAnchorA: {x: 0, y: 0},
+  localAnchorB: {x: 0, y: 0},
+  length: 4.0
+})
+
+console.log("Created distance joint")
+
+// Test multiple steps with joint
+for (var i = 0; i < 10; i++) {
+  world.step(1/60, 4)
+}
+console.log("Body A position after joint simulation:", bodyA.position)
+console.log("Body B position after joint simulation:", bodyB.position)