Merge pull request #18 from paweljarosz/master

Added pendulum example with fixed and spring joints and possibility to change gravity. Changed label in cursor example.

examples/_main/loader.go

@@ -784,3 +784,21 @@ embedded_components {
     w: 1.0
   }
 }
+embedded_components {
+  id: "physics/pendulum"
+  type: "collectionproxy"
+  data: "collection: \"/examples/physics/pendulum/pendulum.collection\"\n"
+  "exclude: false\n"
+  ""
+  position {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+  }
+  rotation {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+    w: 1.0
+  }
+}

examples/_main/menu.gui_script

@@ -102,7 +102,7 @@ function init(self)
 	self.index = { "basics", "physics", "animation", "gui", "input", "particles", "sound", "render", "debug", "collection", "sprite", "file", "tilemap" }
 	self.index = {}
 	self.index["basics"] = { "simple_move", "message_passing", "follow", "parent_child", "spawn", "z_order", "movement_speed" }
-	self.index["physics"] = { "dynamic", "kinematic", "raycast", "trigger", "hinge_joint"}
+	self.index["physics"] = { "dynamic", "kinematic", "raycast", "trigger", "hinge_joint", "pendulum"}
 	self.index["animation"] = { "spinner", "flipbook", "chained_tween", "basic_tween", "spine", "cursor" }
 	self.index["gui"] = { "button", "stencil", "load_texture", "pointer_over", "color"}
 	self.index["input"] = { "move", "text", "down_duration", "mouse_and_touch" }

examples/animation/cursor/cursor.collection

@@ -41,41 +41,41 @@ embedded_instances {
   "  id: \"info\"\n"
   "  type: \"label\"\n"
   "  data: \"size {\\n"
-  "  x: 400.0\\n"
-  "  y: 200.0\\n"
+  "  x: 128.0\\n"
+  "  y: 32.0\\n"
   "  z: 0.0\\n"
   "  w: 0.0\\n"
   "}\\n"
   "scale {\\n"
-  "  x: 1.0\\n"
-  "  y: 1.0\\n"
+  "  x: 0.5\\n"
+  "  y: 0.5\\n"
   "  z: 1.0\\n"
   "  w: 0.0\\n"
   "}\\n"
   "color {\\n"
   "  x: 0.0\\n"
-  "  y: 0.0\\n"
-  "  z: 0.0\\n"
+  "  y: 0.5647059\\n"
+  "  z: 0.99215686\\n"
   "  w: 1.0\\n"
   "}\\n"
   "outline {\\n"
-  "  x: 0.0\\n"
-  "  y: 0.0\\n"
-  "  z: 0.0\\n"
+  "  x: 1.0\\n"
+  "  y: 1.0\\n"
+  "  z: 1.0\\n"
   "  w: 1.0\\n"
   "}\\n"
   "shadow {\\n"
-  "  x: 0.0\\n"
-  "  y: 0.0\\n"
-  "  z: 0.0\\n"
+  "  x: 1.0\\n"
+  "  y: 1.0\\n"
+  "  z: 1.0\\n"
   "  w: 1.0\\n"
   "}\\n"
   "leading: 1.0\\n"
   "tracking: 0.0\\n"
   "pivot: PIVOT_CENTER\\n"
   "blend_mode: BLEND_MODE_ALPHA\\n"
-  "line_break: true\\n"
-  "text: \\\"Click to change cursor animation duration\\\"\\n"
+  "line_break: false\\n"
+  "text: \\\"Click or touch to change duration of cursor animation\\\"\\n"
   "font: \\\"/assets/text48.font\\\"\\n"
   "material: \\\"/builtins/fonts/label.material\\\"\\n"
   "\"\n"

examples/physics/pendulum/pendulum.collection

@@ -0,0 +1,456 @@
+name: "default"
+scale_along_z: 0
+embedded_instances {
+  id: "walls"
+  data: "embedded_components {\n"
+  "  id: \"collisionobject\"\n"
+  "  type: \"collisionobject\"\n"
+  "  data: \"collision_shape: \\\"\\\"\\n"
+  "type: COLLISION_OBJECT_TYPE_STATIC\\n"
+  "mass: 0.0\\n"
+  "friction: 0.9\\n"
+  "restitution: 0.5\\n"
+  "group: \\\"default\\\"\\n"
+  "mask: \\\"default\\\"\\n"
+  "embedded_collision_shape {\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_BOX\\n"
+  "    position {\\n"
+  "      x: 360.0\\n"
+  "      y: 770.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 0\\n"
+  "    count: 3\\n"
+  "  }\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_BOX\\n"
+  "    position {\\n"
+  "      x: 770.0\\n"
+  "      y: 360.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 3\\n"
+  "    count: 3\\n"
+  "  }\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_BOX\\n"
+  "    position {\\n"
+  "      x: -50.0\\n"
+  "      y: 360.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 6\\n"
+  "    count: 3\\n"
+  "  }\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_BOX\\n"
+  "    position {\\n"
+  "      x: 360.0\\n"
+  "      y: -50.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 9\\n"
+  "    count: 3\\n"
+  "  }\\n"
+  "  data: 460.0\\n"
+  "  data: 50.0\\n"
+  "  data: 10.0\\n"
+  "  data: 50.0\\n"
+  "  data: 360.0\\n"
+  "  data: 10.0\\n"
+  "  data: 50.0\\n"
+  "  data: 360.0\\n"
+  "  data: 10.0\\n"
+  "  data: 460.0\\n"
+  "  data: 50.0\\n"
+  "  data: 10.0\\n"
+  "}\\n"
+  "linear_damping: 0.0\\n"
+  "angular_damping: 0.0\\n"
+  "locked_rotation: false\\n"
+  "bullet: false\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  "embedded_components {\n"
+  "  id: \"label\"\n"
+  "  type: \"label\"\n"
+  "  data: \"size {\\n"
+  "  x: 128.0\\n"
+  "  y: 32.0\\n"
+  "  z: 0.0\\n"
+  "  w: 0.0\\n"
+  "}\\n"
+  "scale {\\n"
+  "  x: 0.5\\n"
+  "  y: 0.5\\n"
+  "  z: 1.0\\n"
+  "  w: 0.0\\n"
+  "}\\n"
+  "color {\\n"
+  "  x: 0.0\\n"
+  "  y: 0.5647059\\n"
+  "  z: 0.99215686\\n"
+  "  w: 1.0\\n"
+  "}\\n"
+  "outline {\\n"
+  "  x: 1.0\\n"
+  "  y: 1.0\\n"
+  "  z: 1.0\\n"
+  "  w: 1.0\\n"
+  "}\\n"
+  "shadow {\\n"
+  "  x: 1.0\\n"
+  "  y: 1.0\\n"
+  "  z: 1.0\\n"
+  "  w: 1.0\\n"
+  "}\\n"
+  "leading: 1.0\\n"
+  "tracking: 0.0\\n"
+  "pivot: PIVOT_CENTER\\n"
+  "blend_mode: BLEND_MODE_ALPHA\\n"
+  "line_break: false\\n"
+  "text: \\\"Click or touch to change gravity direction\\\"\\n"
+  "font: \\\"/assets/text48.font\\\"\\n"
+  "material: \\\"/builtins/fonts/label.material\\\"\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 360.0\n"
+  "    y: 558.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  ""
+  position {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+  }
+  rotation {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+    w: 1.0
+  }
+  scale3 {
+    x: 1.0
+    y: 1.0
+    z: 1.0
+  }
+}
+embedded_instances {
+  id: "pivot"
+  data: "components {\n"
+  "  id: \"script\"\n"
+  "  component: \"/examples/physics/pendulum/pendulum.script\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  "embedded_components {\n"
+  "  id: \"sprite\"\n"
+  "  type: \"sprite\"\n"
+  "  data: \"tile_set: \\\"/assets/sprites.atlas\\\"\\n"
+  "default_animation: \\\"elementStone023\\\"\\n"
+  "material: \\\"/builtins/materials/sprite.material\\\"\\n"
+  "blend_mode: BLEND_MODE_ALPHA\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  "embedded_components {\n"
+  "  id: \"collisionobject\"\n"
+  "  type: \"collisionobject\"\n"
+  "  data: \"collision_shape: \\\"\\\"\\n"
+  "type: COLLISION_OBJECT_TYPE_STATIC\\n"
+  "mass: 0.0\\n"
+  "friction: 0.1\\n"
+  "restitution: 0.1\\n"
+  "group: \\\"default\\\"\\n"
+  "mask: \\\"default\\\"\\n"
+  "embedded_collision_shape {\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_BOX\\n"
+  "    position {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 0\\n"
+  "    count: 3\\n"
+  "  }\\n"
+  "  data: 67.5\\n"
+  "  data: 67.5\\n"
+  "  data: 10.0\\n"
+  "}\\n"
+  "linear_damping: 0.0\\n"
+  "angular_damping: 0.0\\n"
+  "locked_rotation: false\\n"
+  "bullet: false\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  ""
+  position {
+    x: 360.0
+    y: 360.0
+    z: 0.0
+  }
+  rotation {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+    w: 1.0
+  }
+  scale3 {
+    x: 1.0
+    y: 1.0
+    z: 1.0
+  }
+}
+embedded_instances {
+  id: "weight_fixed"
+  data: "embedded_components {\n"
+  "  id: \"collisionobject\"\n"
+  "  type: \"collisionobject\"\n"
+  "  data: \"collision_shape: \\\"\\\"\\n"
+  "type: COLLISION_OBJECT_TYPE_DYNAMIC\\n"
+  "mass: 5.0\\n"
+  "friction: 0.9\\n"
+  "restitution: 0.1\\n"
+  "group: \\\"default\\\"\\n"
+  "mask: \\\"default\\\"\\n"
+  "embedded_collision_shape {\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_SPHERE\\n"
+  "    position {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 0\\n"
+  "    count: 1\\n"
+  "  }\\n"
+  "  data: 35.0\\n"
+  "}\\n"
+  "linear_damping: 0.0\\n"
+  "angular_damping: 0.0\\n"
+  "locked_rotation: false\\n"
+  "bullet: false\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  "embedded_components {\n"
+  "  id: \"sprite\"\n"
+  "  type: \"sprite\"\n"
+  "  data: \"tile_set: \\\"/assets/sprites.atlas\\\"\\n"
+  "default_animation: \\\"elementMetal001\\\"\\n"
+  "material: \\\"/builtins/materials/sprite.material\\\"\\n"
+  "blend_mode: BLEND_MODE_ALPHA\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  ""
+  position {
+    x: 210.0
+    y: 140.0
+    z: 1.0
+  }
+  rotation {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+    w: 1.0
+  }
+  scale3 {
+    x: 1.0
+    y: 1.0
+    z: 1.0
+  }
+}
+embedded_instances {
+  id: "weight_spring"
+  data: "embedded_components {\n"
+  "  id: \"collisionobject\"\n"
+  "  type: \"collisionobject\"\n"
+  "  data: \"collision_shape: \\\"\\\"\\n"
+  "type: COLLISION_OBJECT_TYPE_DYNAMIC\\n"
+  "mass: 5.0\\n"
+  "friction: 0.9\\n"
+  "restitution: 0.1\\n"
+  "group: \\\"default\\\"\\n"
+  "mask: \\\"default\\\"\\n"
+  "embedded_collision_shape {\\n"
+  "  shapes {\\n"
+  "    shape_type: TYPE_SPHERE\\n"
+  "    position {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "    }\\n"
+  "    rotation {\\n"
+  "      x: 0.0\\n"
+  "      y: 0.0\\n"
+  "      z: 0.0\\n"
+  "      w: 1.0\\n"
+  "    }\\n"
+  "    index: 0\\n"
+  "    count: 1\\n"
+  "  }\\n"
+  "  data: 35.0\\n"
+  "}\\n"
+  "linear_damping: 0.0\\n"
+  "angular_damping: 0.0\\n"
+  "locked_rotation: false\\n"
+  "bullet: false\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  "embedded_components {\n"
+  "  id: \"sprite\"\n"
+  "  type: \"sprite\"\n"
+  "  data: \"tile_set: \\\"/assets/sprites.atlas\\\"\\n"
+  "default_animation: \\\"elementMetal001\\\"\\n"
+  "material: \\\"/builtins/materials/sprite.material\\\"\\n"
+  "blend_mode: BLEND_MODE_ALPHA\\n"
+  "\"\n"
+  "  position {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "  }\n"
+  "  rotation {\n"
+  "    x: 0.0\n"
+  "    y: 0.0\n"
+  "    z: 0.0\n"
+  "    w: 1.0\n"
+  "  }\n"
+  "}\n"
+  ""
+  position {
+    x: 87.0
+    y: 144.0
+    z: 1.0
+  }
+  rotation {
+    x: 0.0
+    y: 0.0
+    z: 0.0
+    w: 1.0
+  }
+  scale3 {
+    x: 1.0
+    y: 1.0
+    z: 1.0
+  }
+}

examples/physics/pendulum/pendulum.md

@@ -0,0 +1,28 @@
+---
+title: Pendulum physics
+brief: This example shows a simple setup with a static pivot and two dynamic weights - physics objects joined together with a joint of type "fixed" and "spring". The fixed joint can simulate a rope and spring joint a spring. The example shows how to create the joints and change the gravity to affect the pendulums.
+scripts: pendulum.script
+---
+
+![pendulum](pendulum.png)
+
+The setup consists of four game objects. The *game.project* physics *GravityY* property is set to -500 to match the scale of the setup.
+
+pivot
+: The square stone block. Contains:
+  - A *Sprite* component with the stone block image.
+  - A *Collision object* component. The *Type* is set to `STATIC`. A box *Shape* matching the sprite image is added to the components.
+  - A script that joines the weights game objects to to the pivot and reacts to user input by changing the direction of the physics gravity.
+  - A label with an instruction to the user.
+
+weight_fixed
+: The cirular metal weight. Contains:
+  - A *Sprite* component with the metal circle image.
+  - A *Collision object* component. Also has *Type* set to `DYNAMIC`. A box *Shape* matching the sprite image is added to the component.
+
+weight_spring
+: The same as above.
+
+walls
+: The outer walls. Contains:
+  - A *Collision object* component. The *Type* is set to `STATIC`. 4 box *Shapes* are added to the component. These are placed just outside of the game view.

examples/physics/pendulum/pendulum.script

@@ -0,0 +1,52 @@
+local function draw_line(from, to)
+	msg.post("@render:", "draw_line", { start_point = from, end_point = to, color = vmath.vector4(1,0,0,1) }) -- <1>
+end
+
+function init(self)
+	msg.post(".", "acquire_input_focus") -- <2>
+	self.gravity = physics.get_gravity() -- <3>
+	self.pivot_pos = go.get_position()   -- <4>
+
+	local center_anchor = vmath.vector3(0, 0, 0) -- <5>
+	local pivot = "pivot#collisionobject"
+	local weight_fixed = "weight_fixed#collisionobject"
+	local weight_spring = "weight_spring#collisionobject"
+	physics.create_joint(physics.JOINT_TYPE_FIXED, weight_fixed, "weight_fixed_joint", center_anchor, pivot, center_anchor, {max_length = 250}) -- <6>
+	physics.create_joint(physics.JOINT_TYPE_SPRING, weight_spring, "weight_spring_joint", center_anchor, pivot, center_anchor, {length = 150, frequency = 1, damping = 0}) -- <7>
+end
+
+function update(self, dt)
+	local weight_pos = go.get_position("/weight_fixed") -- <8>
+	local weight1_pos = go.get_position("/weight_spring")
+	draw_line(self.pivot_pos, weight_pos)  -- <9>
+	draw_line(self.pivot_pos, weight1_pos)
+end
+
+
+function on_input(self, action_id, action)
+	if action_id == hash("touch") and action.pressed then -- <10>
+		if self.gravity.y ~= 0 then -- <11>
+			self.gravity.y = 0
+			self.gravity.x = 500
+		else
+			self.gravity.y = -500
+			self.gravity.x = 0
+		end
+		physics.set_gravity(self.gravity) -- <12>
+	end
+end
+
+--[[
+1. Helper function to draw a line between two points.
+2. Tell the engine that this object ("." is shorthand for the current game object) should listen to input. Any input will be received in the `on_input()` function.
+3. Get current physics gravity vector and store it in self reference to change it later.
+4. Get current position of the pivot and store it in self reference for drawing a line between the pivot and weights.
+5. Store vector used for anchoring joints and collision objects ids in local variables for ease of use in below function.
+6. Create a fixed joint between a first weight and the pivot
+7. create a spring type joing between the second weight and the pivot.
+8. Get updated positions of both weights.
+9. Draw lines between the weights and the pivot.
+10. If we receive input (touch or mouse click) we switch the direction of the gravity pull.
+11. If the gravity is set to the bottom of the screen, set it so it pulls to the right, in other case, set it back to pull to the bottom.
+12. Set the new gravity vector.
+--]]