Added Box2D Distance joint example.

physics/box2d_distance_joint/all.texture_profiles

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+path_settings {
+  path: "**"
+  profile: "Default"
+}
+profiles {
+  name: "Default"
+  platforms {
+    os: OS_ID_GENERIC
+    formats {
+      format: TEXTURE_FORMAT_RGBA
+      compression_level: BEST
+      compression_type: COMPRESSION_TYPE_DEFAULT
+    }
+    mipmaps: false
+    max_texture_size: 0
+    premultiply_alpha: true
+  }
+}

physics/box2d_distance_joint/box2d_v2.appmanifest

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+  wasm-web:
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+  wasm_pthread-web:
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physics/box2d_distance_joint/box2d_v3.appmanifest

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+platforms:
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+    context:
+      excludeLibs: [physics, box2d_defold, script_box2d_defold]
+      excludeSymbols: []
+      libs: [physics_2d, box2d, script_box2d, physics_3d]
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+    context:
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physics/box2d_distance_joint/example.md

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+---
+tags: physics, box2d
+title: Box2D Distance Joint
+brief: Compare a rigid distance joint with the same joint configured as a damped spring.
+author_ids:
+  - defold-foundation
+scripts: box2d_distance_joint.script
+thumbnail: thumbnail.webp
+---
+
+A distance joint keeps two body anchor points at a specified distance. It can also behave like a damped spring when spring behavior, hertz, and damping ratio are configured.
+
+This example suspends two platforms from pairs of distance joints. Identical balls drop onto both at the same time: the rigid platform preserves both joint lengths, while the spring platform stretches, rebounds, oscillates, and settles.
+
+The balls are dropped automatically every 5.5 seconds.
+
+## What You'll Learn
+
+- How to create distance joints with `b2d.joint.create_distance()`
+- How local anchors connect a platform at two distinct attachment points
+- How `enable_spring`, `hertz`, and `damping_ratio` configure rigid and spring behavior
+- How to read current world-space joint anchors for visualization
+- How to reset existing physics bodies for a repeated demonstration
+- How to repeat an action with `timer.delay()`
+
+## Setup
+
+The collection contains two arrangements separated by a static wall divider:
+
+`rigid_left_anchor`, `rigid_right_anchor`, and `rigid_platform`
+: Two static supports and one dynamic platform connected by rigid distance joints.
+
+`spring_left_anchor`, `spring_right_anchor`, and `spring_platform`
+: An identical arrangement whose distance joints use a spring frequency of 1.35 Hz and a damping ratio of 0.25.
+
+`rigid_ball` and `spring_ball`
+: Identical dynamic balls that are reset at the same height to drop on the platforms in the scene.
+
+`controller`
+: Contains the shared script and the labels with information, like title, hint, `RIGID`, and `SPRING`.
+
+`wall`
+: A static vertical divider between the two arrangements.
+
+![setup](setup.png)
+
+The `game.project` of this example is configured to build with `/box2d_v3.appmanifest` by default.
+To test V2 locally after downloading the example, change `Native Extensions -> App Manifest` in `game.project` to `/box2d_v2.appmanifest`.
+
+## How It Works
+
+Each platform is connected at two points near its ends. A distance joint constrains only the separation between its two anchors, so the platform remains free to swing, tilt, and rotate. This differs from a revolute joint, which brings two local anchors together at one shared hinge point while allowing relative rotation.
+
+For the rigid setup, both joints have a fixed length and spring behavior is disabled. The upper anchors are closer together than the platform attachment points, which lets an off-center impact visibly couple sideways swing with platform rotation. For the spring setup, the same length is used as the spring rest length, with a given frequency and a damping ratio. Hertz controls how quickly the spring responds and therefore how stiff it feels. Damping ratio controls how quickly oscillation is removed.
+
+Every frame, the script calls `b2d.joint.get_anchor_a()` and `b2d.joint.get_anchor_b()` and draws a line between those current world-space positions. The lower endpoints therefore stay attached to the correct points as each platform moves and rotates.
+
+The same two authored ball bodies are moved back above the platforms every few seconds by a repeating `timer.delay()`. Their linear and angular motion is reset, so the comparison repeats without factories or accumulating objects.

physics/box2d_distance_joint/example/anchor.go

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+embedded_components {
+  id: "sprite"
+  type: "sprite"
+  data: "default_animation: \"pixel_gold\"\n"
+  "material: \"/builtins/materials/sprite.material\"\n"
+  "size {\n"
+  "  x: 24.0\n"
+  "  y: 24.0\n"
+  "}\n"
+  "size_mode: SIZE_MODE_MANUAL\n"
+  "textures {\n"
+  "  sampler: \"texture_sampler\"\n"
+  "  texture: \"/textures/textures.atlas\"\n"
+  "}\n"
+  ""
+}
+embedded_components {
+  id: "collisionobject"
+  type: "collisionobject"
+  data: "type: COLLISION_OBJECT_TYPE_STATIC\n"
+  "mass: 0.0\n"
+  "friction: 0.5\n"
+  "restitution: 0.0\n"
+  "group: \"default\"\n"
+  "mask: \"default\"\n"
+  "embedded_collision_shape {\n"
+  "  shapes {\n"
+  "    shape_type: TYPE_BOX\n"
+  "    position {\n"
+  "    }\n"
+  "    rotation {\n"
+  "    }\n"
+  "    index: 0\n"
+  "    count: 3\n"
+  "  }\n"
+  "  data: 12.0\n"
+  "  data: 12.0\n"
+  "  data: 10.0\n"
+  "}\n"
+  ""
+}

physics/box2d_distance_joint/example/ball.go

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+embedded_components {
+  id: "sprite"
+  type: "sprite"
+  data: "default_animation: \"ball\"\n"
+  "material: \"/builtins/materials/sprite.material\"\n"
+  "size {\n"
+  "  x: 64.0\n"
+  "  y: 64.0\n"
+  "}\n"
+  "size_mode: SIZE_MODE_MANUAL\n"
+  "textures {\n"
+  "  sampler: \"texture_sampler\"\n"
+  "  texture: \"/textures/textures.atlas\"\n"
+  "}\n"
+  ""
+}
+embedded_components {
+  id: "collisionobject"
+  type: "collisionobject"
+  data: "type: COLLISION_OBJECT_TYPE_DYNAMIC\n"
+  "mass: 2.0\n"
+  "friction: 0.5\n"
+  "restitution: 0.15\n"
+  "group: \"default\"\n"
+  "mask: \"default\"\n"
+  "embedded_collision_shape {\n"
+  "  shapes {\n"
+  "    shape_type: TYPE_SPHERE\n"
+  "    position {\n"
+  "    }\n"
+  "    rotation {\n"
+  "    }\n"
+  "    index: 0\n"
+  "    count: 1\n"
+  "  }\n"
+  "  data: 32.0\n"
+  "}\n"
+  ""
+}