mediafragments work for ogg

2026-06-18 15:13:30 +02:00 · 2026-06-18 15:13:30 +02:00 · cd480daccc
commit cd480daccc
parent 97b14f7910
21 changed files with 741 additions and 113 deletions
--- a/README.md
+++ b/README.md
@ -7,9 +7,10 @@ Download/run the binaries for your platform in the releases section.<br>
 Developers can run it via [Lua](https://lua.org), [LÖVR](https://lovr.org) or [LÖVE2D](https://love2d.org)

 ```
-$ love xurfer <url> [..]         # if you have LÖVE2D installed (>v12)
-$ lovr xurfer <url> [..]         # if you have LÖVR installed
-$ lua xurfer/main.lua <url> [..] # if you have lua installed
+$ cd xurfer
+$ love . <url_or_file> [..]       # if you have LÖVE2D installed (>v12)
+$ lovr . <url_or_file> [..]       # if you have LÖVR installed
+$ lua main.lua <url_or_file> [..] # if you have lua installed
 ```

 **Example**: lovr xurfer <a href="https://snips.sh/f/_U5-XctEVE?r=1">https://snips.sh/f/_U5-XctEVE?r=1</a>
--- a/xurfer/conf.lua
+++ b/xurfer/conf.lua
@ -11,5 +11,4 @@ package.path = package.path .. ';' ..
               arg[0] .. '/' .. runtime .. '/?/init.lua;' .. 
               arg[0] .. '/lib/?.lua'

-
 require( runtime .. "/conf")
--- a/xurfer/ecs.lua
+++ b/xurfer/ecs.lua
@ -7,8 +7,16 @@ ecs.init = function()
  baseEntify.updatethread = true
  function baseEntify:onAdd(obj)
    obj.commit = api.util.commit( api.world, obj, api )
+    api.world.commit = api.util.commit( api.world, false, api)
  end
  ecs.addSystem( api.world, baseEntify )
 end

+ecs.clear = function()
+  api.ext.exec("onClear")
+  api.ecs.clearEntities( api.world )
+  api.ecs.update( api.world )
+  api.world.commit()
+end
+
 return ecs
--- a/xurfer/ext/3DFile/main.lua
+++ b/xurfer/ext/3DFile/main.lua
@ -6,16 +6,26 @@ return {
  enabled = true,

  onURI = function(obj)
-    if( obj.URL ~= nil and obj.URLResponse ~= nil and
+    if( obj.URL ~= nil and (obj.URLResponse ~= nil or obj.URL.protocol == 'file') and
       (obj.URL.extension == 'GLB'   or
        obj.URL.extension == 'GLTF'  or 
        obj.URL.extension == 'OBJ')) then 
-      if obj.URLResponse.ok then 
-        obj.model = api.graphics.newModel( api.data.newBlob( obj.URLResponse.data) )
-        obj.root  = (obj.URI.target == '_top')
-        if obj.x == nil then obj.x = 0 end
-        if obj.y == nil then obj.y = 0 end
-        if obj.z == nil then obj.z = 0 end
+      if obj.URLResponse.ok or obj.URL.protocol == 'file' then 
+        obj.root  = false 
+        if obj.URI.target == '_top' then
+          obj.root = true
+          api.ext.URI.current = obj.URL -- set current url
+        end
+        obj.x = obj.x or 0
+        obj.y = obj.y or 0
+        obj.z = obj.z or 0
+        obj.scale = obj.scale or 1
+        if obj.URL.protocol == 'file' then
+          obj.model = api.graphics.newModel( obj.URL.string )
+        else
+          obj.model = api.graphics.newModel( api.data.newBlob( obj.URLResponse.data) )
+        end
+        api.ecs.add( api.world, obj )
        obj.commit('on3DFile') -- notify systems
      else
        print("[3DFile] error: could not load " .. obj.URL.string )
--- a/xurfer/ext/AudioFile/main.lua
+++ b/xurfer/ext/AudioFile/main.lua
@ -0,0 +1,34 @@
+local api = ...
+local ecs = api.ecs
+
+return {
+  name = "AudioFile",
+  enabled = true,
+
+  onURI = function(obj)
+    if( obj.URL ~= nil and (obj.URLResponse ~= nil or obj.URL.protocol == 'file') and
+       (obj.URL.extension == 'OGG'   or
+        obj.URL.extension == 'WAV'  or 
+        obj.URL.extension == 'MP3')) then 
+      if obj.URLResponse.ok or obj.URL.protocol == 'file' then 
+        obj.x = obj.x or 0
+        obj.y = obj.y or 0
+        obj.z = obj.z or 0
+        local opts = {
+          spatial = obj.x == 0 and obj.y == 0 and obj.z == 0
+        }
+        if obj.URL.protocol == 'file' then
+          obj.audio = api.audio.newSource( obj.URL.file, opts)
+        else
+          obj.audio = api.audio.newSource( api.data.newBlob( obj.URLResponse.data), opts )
+        end
+        api.ecs.add( api.world, obj )
+        obj.commit('onAudioFile') -- notify systems
+        obj.audio:play()
+      else
+        print("[AudioFile] error: could not load " .. obj.URL.string )
+      end
+    end
+  end
+
+}
--- a/xurfer/ext/URI/main.lua
+++ b/xurfer/ext/URI/main.lua
@ -4,6 +4,7 @@ local ecs = api.ecs
 return {
  name = "URI",
  enabled = true,
+  current = {}, -- will hold the most recent (_top) URL object

  init = function() 
    local urlListener 
@ -19,23 +20,27 @@ return {

  to = function(URI,refererer, obj)
    obj = obj or {}
-    local msg = "[i] loading"
-    print("[i] loading " .. URI.url)
+    print("[i] loading URL: " .. URI.url)
    obj.URL = api.url.parse(URI.url) 
    obj.URLResponse = {}
+    local protocol = "file"
    foreach( api.protocol, function(name, p)
      if obj.URL.protocol:match("^"..name) then 
        protocol = p
      end
    end)
    if protocol then
+      if obj.URL.protocol == 'file' then 
+        return obj.commit('onURI') 
+      end
      local status, data, headers = protocol.request(URI.url)
      obj.URLResponse = {
-        ok          = (status >= 200 and status < 300),
+        ok          = (status ~= nil and status >= 200 and status < 300),
        status      = status,
        data        = data,
        headers     = headers 
      }
+      api.ecs.add( api.world, obj )
      obj.commit('onURI')
    end
  end
--- a/xurfer/ext/kitchensink/main.lua
+++ b/xurfer/ext/kitchensink/main.lua
@ -4,7 +4,7 @@ local sample

 return {
  name = "kitchensink",
-  enabled = (lover ~= nil),
+  enabled = false, --(lovr ~= nil),

  init = function() 
    sample = require "sample"
--- a/xurfer/ext/startupscene/main.lua
+++ b/xurfer/ext/startupscene/main.lua
@ -1,13 +1,10 @@
 local api = ...
 local envTex
-local skybox
-local environmentMap
-local sphericalHarmonics
 local shader
    
 return {
  name = "startupscene",
-  enabled = true,
+  enabled = (lovr ~= nil),

  init = function() end,

@ -19,8 +16,8 @@ return {

  load = function()
    --if api.iui.idiom == "vr" then
-      envTex = lovr.graphics.newTexture("lovr/assets/img/env.png", {})
-      skybox = lovr.graphics.newTexture({
+      envTex = api.graphics.newTexture("lovr/assets/img/env.png", {})
+      api.world.skybox = api.graphics.newTexture({
        px = 'ext/startupscene/skybox/Dayright.jpg',  -- 'px.png',
        nx = 'ext/startupscene/skybox/Dayleft.jpg',   -- 'nx.png',
        py = 'ext/startupscene/skybox/Daytop.jpg',    -- 'py.png',
@ -28,9 +25,9 @@ return {
        pz = 'ext/startupscene/skybox/Dayfront.jpg',  -- 'pz.png',
        nz = 'ext/startupscene/skybox/Dayback.jpg'    -- 'nz.png'
      })
-      environmentMap = lovr.graphics.newTexture('ext/startupscene/skybox/ibl.ktx')
+      api.world.environmentMap = lovr.graphics.newTexture('ext/startupscene/skybox/ibl.ktx')

-      sphericalHarmonics = lovr.graphics.newBuffer({ 'vec3', layout = 'std140' }, {
+      api.world.sphericalHarmonics = lovr.graphics.newBuffer({ 'vec3', layout = 'std140' }, {
        {  0.611764907836914,  0.599504590034485,  0.479980736970901 },
        {  0.659514904022217,  0.665349841117859,  0.567680120468140 },
        {  0.451633930206299,  0.450751245021820,  0.355226665735245 },
@ -41,36 +38,6 @@ return {
        { -0.179465517401695, -0.181243389844894, -0.141314014792442 },
        { -0.144527092576027, -0.143508568406105, -0.122757166624069 }
      })
-      shader = lovr.graphics.newShader([[
-        vec4 lovrmain() {
-          return DefaultPosition;
-        }
-      ]], [[
-        uniform textureCube cubemap;
-        uniform sphericalHarmonics { vec3 sh[9]; };
-
-        vec4 lovrmain() {
-          Surface surface;
-          initSurface(surface);
-
-          vec3 color = vec3(0);
-          vec3 lightDirection = vec3(-1, -1, -1);
-          vec4 lightColorAndBrightness = vec4(1, 1, 1, 3);
-          float visibility = 1.;
-          color += getLighting(surface, lightDirection, lightColorAndBrightness, visibility);
-          color += getIndirectLighting(surface, cubemap, sh);
-
-          return vec4(color, 1);
-        }
-      ]], {
-        flags = {
-          glow = true,
-          normalMap = true,
-          vertexTangents = false, -- DamagedHelmet doesn't have vertex tangents
-          tonemap = true
-        }
-      })
-    --end
  end,

  draw = function(pass)
@ -78,7 +45,7 @@ return {
        -- skybox
        pass:setCullMode('back')
        pass:setBlendMode()
-        pass:skybox(skybox)
+        pass:skybox(api.world.skybox)

        pass:setColor(1, 1, 1)
        pass:setMaterial(envTex)
@ -94,9 +61,9 @@ return {
        pass:setColor( 0, 0, 0, 0.75 )
        pass:plane(0, 0.01, 0, 500, 500, math.pi * 0.5, 1, 0, 0, "line", 100, 100)
 
-        pass:setShader(shader)
-        pass:send('cubemap', environmentMap)
-        pass:send('sphericalHarmonics', sphericalHarmonics)
+        pass:setShader( lovr.shader.pbr ) 
+        pass:send('cubemap', api.world.environmentMap)
+        pass:send('sphericalHarmonics', api.world.sphericalHarmonics)

    end
  end
--- a/xurfer/ext/tween/main.lua
+++ b/xurfer/ext/tween/main.lua
@ -0,0 +1,33 @@
+local api = ...
+
+return {
+  enabled = false,
+
+  init = function()
+    local tweenUpdater = api.ecs.processingSystem({
+      updatethread = true,
+      filter = api.ecs.requireAll('tween'),
+      nocache = true,
+      process = function( self, obj, dt)
+        print("JAAA")
+        foreach( obj.tween, function(k,t)
+          print("TWEENING!")
+          if t:update(dt) == true then 
+            obj.tween[k] = nil -- delete tween
+            if count(obj.tween) == 0 then 
+              obj.tween = nil 
+              print("deleted tweens")
+            end
+          end
+        end)
+      end
+    })
+    api.ecs.addSystem( api.world, tweenUpdater )
+  end
+
+            ---- visualize click
+            --onClick
+            --obj.scale = 0.66 
+            --obj.tween          = obj.tween or {}
+            --obj.tween['scale'] = tween.new(0.5, obj, {scale = 1})
+}
--- a/xurfer/ext/tween/tween.lua
+++ b/xurfer/ext/tween/tween.lua
@ -0,0 +1,367 @@
+local tween = {
+  _VERSION     = 'tween 2.1.1',
+  _DESCRIPTION = 'tweening for lua',
+  _URL         = 'https://github.com/kikito/tween.lua',
+  _LICENSE     = [[
+    MIT LICENSE
+
+    Copyright (c) 2014 Enrique García Cota, Yuichi Tateno, Emmanuel Oga
+
+    Permission is hereby granted, free of charge, to any person obtaining a
+    copy of this software and associated documentation files (the
+    "Software"), to deal in the Software without restriction, including
+    without limitation the rights to use, copy, modify, merge, publish,
+    distribute, sublicense, and/or sell copies of the Software, and to
+    permit persons to whom the Software is furnished to do so, subject to
+    the following conditions:
+
+    The above copyright notice and this permission notice shall be included
+    in all copies or substantial portions of the Software.
+
+    THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
+    OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+    IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+    CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+    TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+    SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+  ]]
+}
+
+-- easing
+
+-- Adapted from https://github.com/EmmanuelOga/easing. See LICENSE.txt for credits.
+-- For all easing functions:
+-- t = time == how much time has to pass for the tweening to complete
+-- b = begin == starting property value
+-- c = change == ending - beginning
+-- d = duration == running time. How much time has passed *right now*
+
+local pow, sin, cos, pi, sqrt, abs, asin = math.pow, math.sin, math.cos, math.pi, math.sqrt, math.abs, math.asin
+
+-- linear
+local function linear(t, b, c, d) return c * t / d + b end
+
+-- quad
+local function inQuad(t, b, c, d) return c * pow(t / d, 2) + b end
+local function outQuad(t, b, c, d)
+  t = t / d
+  return -c * t * (t - 2) + b
+end
+local function inOutQuad(t, b, c, d)
+  t = t / d * 2
+  if t < 1 then return c / 2 * pow(t, 2) + b end
+  return -c / 2 * ((t - 1) * (t - 3) - 1) + b
+end
+local function outInQuad(t, b, c, d)
+  if t < d / 2 then return outQuad(t * 2, b, c / 2, d) end
+  return inQuad((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+-- cubic
+local function inCubic (t, b, c, d) return c * pow(t / d, 3) + b end
+local function outCubic(t, b, c, d) return c * (pow(t / d - 1, 3) + 1) + b end
+local function inOutCubic(t, b, c, d)
+  t = t / d * 2
+  if t < 1 then return c / 2 * t * t * t + b end
+  t = t - 2
+  return c / 2 * (t * t * t + 2) + b
+end
+local function outInCubic(t, b, c, d)
+  if t < d / 2 then return outCubic(t * 2, b, c / 2, d) end
+  return inCubic((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+-- quart
+local function inQuart(t, b, c, d) return c * pow(t / d, 4) + b end
+local function outQuart(t, b, c, d) return -c * (pow(t / d - 1, 4) - 1) + b end
+local function inOutQuart(t, b, c, d)
+  t = t / d * 2
+  if t < 1 then return c / 2 * pow(t, 4) + b end
+  return -c / 2 * (pow(t - 2, 4) - 2) + b
+end
+local function outInQuart(t, b, c, d)
+  if t < d / 2 then return outQuart(t * 2, b, c / 2, d) end
+  return inQuart((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+-- quint
+local function inQuint(t, b, c, d) return c * pow(t / d, 5) + b end
+local function outQuint(t, b, c, d) return c * (pow(t / d - 1, 5) + 1) + b end
+local function inOutQuint(t, b, c, d)
+  t = t / d * 2
+  if t < 1 then return c / 2 * pow(t, 5) + b end
+  return c / 2 * (pow(t - 2, 5) + 2) + b
+end
+local function outInQuint(t, b, c, d)
+  if t < d / 2 then return outQuint(t * 2, b, c / 2, d) end
+  return inQuint((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+-- sine
+local function inSine(t, b, c, d) return -c * cos(t / d * (pi / 2)) + c + b end
+local function outSine(t, b, c, d) return c * sin(t / d * (pi / 2)) + b end
+local function inOutSine(t, b, c, d) return -c / 2 * (cos(pi * t / d) - 1) + b end
+local function outInSine(t, b, c, d)
+  if t < d / 2 then return outSine(t * 2, b, c / 2, d) end
+  return inSine((t * 2) -d, b + c / 2, c / 2, d)
+end
+
+-- expo
+local function inExpo(t, b, c, d)
+  if t == 0 then return b end
+  return c * pow(2, 10 * (t / d - 1)) + b - c * 0.001
+end
+local function outExpo(t, b, c, d)
+  if t == d then return b + c end
+  return c * 1.001 * (-pow(2, -10 * t / d) + 1) + b
+end
+local function inOutExpo(t, b, c, d)
+  if t == 0 then return b end
+  if t == d then return b + c end
+  t = t / d * 2
+  if t < 1 then return c / 2 * pow(2, 10 * (t - 1)) + b - c * 0.0005 end
+  return c / 2 * 1.0005 * (-pow(2, -10 * (t - 1)) + 2) + b
+end
+local function outInExpo(t, b, c, d)
+  if t < d / 2 then return outExpo(t * 2, b, c / 2, d) end
+  return inExpo((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+-- circ
+local function inCirc(t, b, c, d) return(-c * (sqrt(1 - pow(t / d, 2)) - 1) + b) end
+local function outCirc(t, b, c, d)  return(c * sqrt(1 - pow(t / d - 1, 2)) + b) end
+local function inOutCirc(t, b, c, d)
+  t = t / d * 2
+  if t < 1 then return -c / 2 * (sqrt(1 - t * t) - 1) + b end
+  t = t - 2
+  return c / 2 * (sqrt(1 - t * t) + 1) + b
+end
+local function outInCirc(t, b, c, d)
+  if t < d / 2 then return outCirc(t * 2, b, c / 2, d) end
+  return inCirc((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+-- elastic
+local function calculatePAS(p,a,c,d)
+  p, a = p or d * 0.3, a or 0
+  if a < abs(c) then return p, c, p / 4 end -- p, a, s
+  return p, a, p / (2 * pi) * asin(c/a) -- p,a,s
+end
+local function inElastic(t, b, c, d, a, p)
+  local s
+  if t == 0 then return b end
+  t = t / d
+  if t == 1  then return b + c end
+  p,a,s = calculatePAS(p,a,c,d)
+  t = t - 1
+  return -(a * pow(2, 10 * t) * sin((t * d - s) * (2 * pi) / p)) + b
+end
+local function outElastic(t, b, c, d, a, p)
+  local s
+  if t == 0 then return b end
+  t = t / d
+  if t == 1 then return b + c end
+  p,a,s = calculatePAS(p,a,c,d)
+  return a * pow(2, -10 * t) * sin((t * d - s) * (2 * pi) / p) + c + b
+end
+local function inOutElastic(t, b, c, d, a, p)
+  local s
+  if t == 0 then return b end
+  t = t / d * 2
+  if t == 2 then return b + c end
+  p,a,s = calculatePAS(p,a,c,d)
+  t = t - 1
+  if t < 0 then return -0.5 * (a * pow(2, 10 * t) * sin((t * d - s) * (2 * pi) / p)) + b end
+  return a * pow(2, -10 * t) * sin((t * d - s) * (2 * pi) / p ) * 0.5 + c + b
+end
+local function outInElastic(t, b, c, d, a, p)
+  if t < d / 2 then return outElastic(t * 2, b, c / 2, d, a, p) end
+  return inElastic((t * 2) - d, b + c / 2, c / 2, d, a, p)
+end
+
+-- back
+local function inBack(t, b, c, d, s)
+  s = s or 1.70158
+  t = t / d
+  return c * t * t * ((s + 1) * t - s) + b
+end
+local function outBack(t, b, c, d, s)
+  s = s or 1.70158
+  t = t / d - 1
+  return c * (t * t * ((s + 1) * t + s) + 1) + b
+end
+local function inOutBack(t, b, c, d, s)
+  s = (s or 1.70158) * 1.525
+  t = t / d * 2
+  if t < 1 then return c / 2 * (t * t * ((s + 1) * t - s)) + b end
+  t = t - 2
+  return c / 2 * (t * t * ((s + 1) * t + s) + 2) + b
+end
+local function outInBack(t, b, c, d, s)
+  if t < d / 2 then return outBack(t * 2, b, c / 2, d, s) end
+  return inBack((t * 2) - d, b + c / 2, c / 2, d, s)
+end
+
+-- bounce
+local function outBounce(t, b, c, d)
+  t = t / d
+  if t < 1 / 2.75 then return c * (7.5625 * t * t) + b end
+  if t < 2 / 2.75 then
+    t = t - (1.5 / 2.75)
+    return c * (7.5625 * t * t + 0.75) + b
+  elseif t < 2.5 / 2.75 then
+    t = t - (2.25 / 2.75)
+    return c * (7.5625 * t * t + 0.9375) + b
+  end
+  t = t - (2.625 / 2.75)
+  return c * (7.5625 * t * t + 0.984375) + b
+end
+local function inBounce(t, b, c, d) return c - outBounce(d - t, 0, c, d) + b end
+local function inOutBounce(t, b, c, d)
+  if t < d / 2 then return inBounce(t * 2, 0, c, d) * 0.5 + b end
+  return outBounce(t * 2 - d, 0, c, d) * 0.5 + c * .5 + b
+end
+local function outInBounce(t, b, c, d)
+  if t < d / 2 then return outBounce(t * 2, b, c / 2, d) end
+  return inBounce((t * 2) - d, b + c / 2, c / 2, d)
+end
+
+tween.easing = {
+  linear    = linear,
+  inQuad    = inQuad,    outQuad    = outQuad,    inOutQuad    = inOutQuad,    outInQuad    = outInQuad,
+  inCubic   = inCubic,   outCubic   = outCubic,   inOutCubic   = inOutCubic,   outInCubic   = outInCubic,
+  inQuart   = inQuart,   outQuart   = outQuart,   inOutQuart   = inOutQuart,   outInQuart   = outInQuart,
+  inQuint   = inQuint,   outQuint   = outQuint,   inOutQuint   = inOutQuint,   outInQuint   = outInQuint,
+  inSine    = inSine,    outSine    = outSine,    inOutSine    = inOutSine,    outInSine    = outInSine,
+  inExpo    = inExpo,    outExpo    = outExpo,    inOutExpo    = inOutExpo,    outInExpo    = outInExpo,
+  inCirc    = inCirc,    outCirc    = outCirc,    inOutCirc    = inOutCirc,    outInCirc    = outInCirc,
+  inElastic = inElastic, outElastic = outElastic, inOutElastic = inOutElastic, outInElastic = outInElastic,
+  inBack    = inBack,    outBack    = outBack,    inOutBack    = inOutBack,    outInBack    = outInBack,
+  inBounce  = inBounce,  outBounce  = outBounce,  inOutBounce  = inOutBounce,  outInBounce  = outInBounce
+}
+
+
+
+-- private stuff
+
+local function copyTables(destination, keysTable, valuesTable)
+  valuesTable = valuesTable or keysTable
+  local mt = getmetatable(keysTable)
+  if mt and getmetatable(destination) == nil then
+    setmetatable(destination, mt)
+  end
+  for k,v in pairs(keysTable) do
+    if type(v) == 'table' then
+      destination[k] = copyTables({}, v, valuesTable[k])
+    else
+      destination[k] = valuesTable[k]
+    end
+  end
+  return destination
+end
+
+local function checkSubjectAndTargetRecursively(subject, target, path)
+  path = path or {}
+  local targetType, newPath
+  for k,targetValue in pairs(target) do
+    targetType, newPath = type(targetValue), copyTables({}, path)
+    table.insert(newPath, tostring(k))
+    if targetType == 'number' then
+      assert(type(subject[k]) == 'number', "Parameter '" .. table.concat(newPath,'/') .. "' is missing from subject or isn't a number")
+    elseif targetType == 'table' then
+      checkSubjectAndTargetRecursively(subject[k], targetValue, newPath)
+    else
+      assert(targetType == 'number', "Parameter '" .. table.concat(newPath,'/') .. "' must be a number or table of numbers")
+    end
+  end
+end
+
+local function checkNewParams(duration, subject, target, easing)
+  assert(type(duration) == 'number' and duration > 0, "duration must be a positive number. Was " .. tostring(duration))
+  local tsubject = type(subject)
+  assert(tsubject == 'table' or tsubject == 'userdata', "subject must be a table or userdata. Was " .. tostring(subject))
+  assert(type(target)== 'table', "target must be a table. Was " .. tostring(target))
+  assert(type(easing)=='function', "easing must be a function. Was " .. tostring(easing))
+  checkSubjectAndTargetRecursively(subject, target)
+end
+
+local function getEasingFunction(easing)
+  easing = easing or "linear"
+  if type(easing) == 'string' then
+    local name = easing
+    easing = tween.easing[name]
+    if type(easing) ~= 'function' then
+      error("The easing function name '" .. name .. "' is invalid")
+    end
+  end
+  return easing
+end
+
+local function performEasingOnSubject(subject, target, initial, clock, duration, easing)
+  local t,b,c,d
+  for k,v in pairs(target) do
+    if type(v) == 'table' then
+      performEasingOnSubject(subject[k], v, initial[k], clock, duration, easing)
+    else
+      t,b,c,d = clock, initial[k], v - initial[k], duration
+      subject[k] = easing(t,b,c,d)
+    end
+  end
+end
+
+-- Tween methods
+
+local Tween = {}
+local Tween_mt = {__index = Tween}
+
+function Tween:set(clock)
+  assert(type(clock) == 'number', "clock must be a positive number or 0")
+
+  self.initial = self.initial or copyTables({}, self.target, self.subject)
+  self.clock = clock
+
+  if self.clock <= 0 then
+
+    self.clock = 0
+    copyTables(self.subject, self.initial)
+
+  elseif self.clock >= self.duration then -- the tween has expired
+
+    self.clock = self.duration
+    copyTables(self.subject, self.target)
+
+  else
+
+    performEasingOnSubject(self.subject, self.target, self.initial, self.clock, self.duration, self.easing)
+
+  end
+
+  return self.clock >= self.duration
+end
+
+function Tween:reset()
+  return self:set(0)
+end
+
+function Tween:update(dt)
+  assert(type(dt) == 'number', "dt must be a number")
+  return self:set(self.clock + dt)
+end
+
+
+-- Public interface
+
+function tween.new(duration, subject, target, easing)
+  easing = getEasingFunction(easing)
+  checkNewParams(duration, subject, target, easing)
+  return setmetatable({
+    duration  = duration,
+    subject   = subject,
+    target    = target,
+    easing    = easing,
+    clock     = 0
+  }, Tween_mt)
+end
+
+return tween
--- a/xurfer/ext/xrfragments/level2.lua
+++ b/xurfer/ext/xrfragments/level2.lua
@ -0,0 +1,16 @@
+local api   = ...
+local xrf   = require("ext/xrfragments/lovr-xrf")
+local url   = require("url")
+
+return {
+
+  load = function( href, obj, refererURL, cb )
+    if xrf.isExternalHref( href ) and not xrf.isImport( href ) then
+      if type(refererURL) ~= 'table' then refererURL = url.parse(refererURL) end
+      local URL = url.getAbsolute( href, refererURL.string )
+      cb( URL.string, obj)
+      return true
+    end
+    return false
+  end
+}
--- a/xurfer/ext/xrfragments/level4.lua
+++ b/xurfer/ext/xrfragments/level4.lua
@ -0,0 +1,15 @@
+local xrf   = require("ext/xrfragments/lovr-xrf")
+local url   = require("url")
+
+return {
+
+  import = function( href, obj, refererURL, cb ) -- imports object
+    if xrf.isImport( href ) then
+      if type(refererURL) ~= 'table' then refererURL = url.parse(refererURL) end
+      local URL = url.getAbsolute( href, refererURL )
+      cb( URL.string, obj )
+      return true
+    end
+    return false
+  end
+}
--- a/xurfer/ext/xrfragments/lovr-xrf.lua
+++ b/xurfer/ext/xrfragments/lovr-xrf.lua
@ -25,6 +25,7 @@
 -- or implied, of  

 local json = require("json") 
+local url  = require("url")
 local xrf  = {}

 xrf.traverseNodesContaining = function(key,obj,cb)
@ -36,14 +37,17 @@ xrf.traverseNodesContaining = function(key,obj,cb)
  for k, tkey in pairs(keys) do 
    local i = 1
    local tree = metadata[tkey]
+    local foundhrefs = false
    xrf.traverse( tree, function(node)
      if node['extras'] ~= nil then 
        if node['extras'][key] ~= nil then
+          foundhrefs = true
          cb(node,obj, i, metadata)
        end
      end
      i = i + 1
    end)
+    if foundhrefs then break end -- blender puts duplicate (undo?) data in 'meshes' sometimes?
  end
 end

@ -86,7 +90,6 @@ xrf.makeClickable = function( physicsWorld, cb)
    local model     = obj['model']
    local node      = node_or_mesh
    if node['mesh'] == nil then node = xrf.getNodeFromMesh(node_or_mesh, metadata, i) end
-    print("making node " .. node['name'] .. " clickable")
    local meshindex = 1 + node['mesh']
    local mesh      = model:getMesh( meshindex )
    local minx, maxx, miny, maxy, minz, maxz = mesh:getBoundingBox()
@ -103,6 +106,7 @@ xrf.makeClickable = function( physicsWorld, cb)
      scale[2] * (h + 0.01), -- in case of 
      scale[3] * (d + 0.01)  -- planes e.g.
    )
+    print("making node " .. node['name'] .. " clickable: " .. node.extras.href )
    collider:setUserData( {name = node['name'], node = node, onclick = cb })
  end 
 end
@ -122,4 +126,18 @@ xrf.traverse = function(arr, cb, key)
  end
 end

+xrf.isImport = function(href)
+  local URL    = href 
+  if type(URL) ~= 'table' then URL = url.parse(href) end
+  return URL.string:find("#!")
+end
+
+xrf.isExternalHref = function(href)
+  local URL    = href 
+  if type(URL) ~= 'table' then URL = url.parse(href) end
+  return (URL.protocol == 'file') and 
+         (URL.string:sub(1,1) ~= '#') and 
+         not xrf.isImport(URL)
+end
+
 return xrf
--- a/xurfer/ext/xrfragments/main.lua
+++ b/xurfer/ext/xrfragments/main.lua
@ -1,9 +1,12 @@
-local api = ...
+local api   = ...
+local url   = require('url')
+local tween = require('tween') 
 local ecs   = api.ecs
-local xrf = require("ext/xrfragments/lovr-xrf")
-local xrfsystem
+local xrf   = require("ext/xrfragments/lovr-xrf")
+xrf.level2  = api.util.addModuleHooks( require("ext/xrfragments/level2") )
+xrf.level4  = api.util.addModuleHooks( require("ext/xrfragments/level4") )

-return {
+xrfimpl = {
  enabled = true,

  init = function() end,
@ -13,12 +16,41 @@ return {
      xrf.traverseNodesContaining('href', obj, 
        xrf.makeClickable( api.ecs.worldPhysics, 
          function(obj, collider)
-            print("\nhref was clicked: " .. obj.node.extras.href)
-            print_r(obj)
+            local href = obj.node.extras.href
+            trace("\n[xrf] href was clicked: " .. href)
+
+            local ok =  xrf.level2.load( href, obj, api.ext.URI.current, xrfimpl.onLoad)
+                        or
+                        xrf.level4.import( href, obj, api.ext.URI.current, xrfimpl.onImport)
+
          end
        )
      )
    end
+  end,
+
+  onAudioFile = function(obj)
+    -- see https://xrfragment.org/#%F0%9F%93%9C%20level3%3A%20Media%20Fragments
+    if obj.audio ~= nil and obj.URL.fragment.t ~= nil then
+      trace("[xrf.level3] seeking to " .. obj.URL.fragment.t .. " seconds in audio")
+      obj.audio:seek( tonumber(obj.URL.fragment.t) ) 
+      obj.audio:setLooping( obj.URL.fragment.loop or false ) 
+    end
+  end,
+
+  onLoad = function(absoluteHref,obj)
+    trace("[xrf.level2] explicit (external) href hyperlink found")
+    api.ecs.clear()
+    api.ecs.add( api.world, { 
+      URI = { url = absoluteHref, method = 'GET', target = '_top' }  
+    })
+  end,
+
+  onImport = function(absoluteHref,obj)
+    trace("[xrf.level4] ! (import) operator found")
+    api.ecs.add( api.world, { URI = { url = absoluteHref, method = 'GET', target = obj }  })
  end

 }
+
+return xrfimpl
--- a/xurfer/ext/xrfragments/url.lua
+++ b/xurfer/ext/xrfragments/url.lua
@ -57,7 +57,9 @@ local function parseArgs(fragment)
    for _, item in ipairs(items) do
        local key_value = split(item, "=")
        if #key_value > 1 then
-            ARG[key_value[1]] = guess_type(key_value[2])
+            local k = key_value[1]
+            ARG[k]                   = guess_type(key_value[2]) -- xr fragment operators preserved
+            ARG[k:gsub("[^%w]","") ] = guess_type(key_value[2]) -- alphanumeric only
        elseif #key_value == 1 then
            ARG[key_value[1]] = ""
        end
@ -67,6 +69,7 @@ end

 -- Main URL Parser function attached to the module object
 function url.parse(url_string)
+    if type(url_string) == 'table' then return url_string end -- already parsed
    -- Setup initial URI table structure
    local URI = {
        domain = "",
@ -86,6 +89,8 @@ function url.parse(url_string)
    if protocol then
        URI.protocol = protocol:gsub("://", "")
        remaining = remaining:sub(#protocol + 1)
+    else
+      URI.protocol = "file"
    end
    local hash = string.match(remaining, "(#.*)$") -- fragment
    if hash then
@ -140,5 +145,17 @@ function url.parse(url_string)
    return URI
 end

+url.getAbsolute = function(href,referer)
+  local URL    = url.parse(href)
+  local URLref = url.parse(referer)
+  if referer ~= nil and URL.protocol == 'file' and URLref.protocol ~= 'file' then 
+    URL.protocol = URLref.protocol 
+    URL.domain   = URLref.domain
+    URL.string   = URLref.protocol .. '://' .. URLref.domain .. '/' .. URL.path .. URL.hash
+    URL.URN      = URL.string:gsub("#.*", "")
+  end
+  return URL
+end
+
 -- Return the module table so it can be assigned via require()
 return url
--- a/xurfer/lib/tiny-ecs.lua
+++ b/xurfer/lib/tiny-ecs.lua
@ -656,8 +656,10 @@ function tiny_manageEntities(world)
                elseif index then
                    system.modified = true
                    local tmpEntity = ses[#ses]
-                    ses[index] = tmpEntity
-                    seis[tmpEntity] = index
+                    if tmpEntity ~= nil then
+                      ses[index] = tmpEntity
+                      seis[tmpEntity] = index
+                    end
                    seis[entity] = nil
                    ses[#ses] = nil
                    local onRemove = system.onRemove
--- a/xurfer/lovr/main.lua
+++ b/xurfer/lovr/main.lua
@ -22,7 +22,6 @@ ecs.filterUpdate = ecs.requireAll('updatethread')

 -- ecs systems
 local interactionsUpdater
-local renderer

 --- @type Texture
 local envTex
@ -120,7 +119,7 @@ end
 if launch.mode == "desktop" then
    function lovr.mousemoved(x, y, dx, dy)
        backend.mousemoved(x, y, dx, dy)
-        interactionsUpdater.mouse.moved = {x=x, y=y, button=button}
+        interactionsUpdater.mouse.moved = {x=x, y=y}
    end

    function lovr.mousepressed(x, y, button)
@ -146,7 +145,7 @@ if launch.mode == "desktop" then

    function lovr.keyreleased(key, scancode)
        backend.keyreleased(key, scancode)
-        interactionsUpdater.key.released = {key=key,scancode=scancode,isRepeat=isRepeat}
+        interactionsUpdater.key.released = {key=key,scancode=scancode}
    end

    function lovr.textinput(text)
@ -155,27 +154,6 @@ if launch.mode == "desktop" then
    end
 end

-local initECS = function(ecs)
-  -- lovr.draw => ecs.draw (render-logic thread)
-  renderer = ecs.processingSystem()
-  renderer.filter        = ecs.requireAll('model') 
-  renderer.drawthread = true
-  function renderer:process(obj, pass)
-    if obj.model ~= nil and obj.root ~= nil then 
-      pass:setMaterial()
-      pass:setCullMode('none')
-      pass:draw(
-        obj['model'], 
-        obj['x'], 
-        obj['y'],
-        obj['z'], 
-        1, 0, 1, 0, 0, 1)
-    end
-  end
-  ecs.addSystem( api.world, renderer )
-
-end
-
 function initInteractions(ecs)

  ecs.worldPhysics = lovr.physics.newWorld(0, 0, 0)
@ -198,14 +176,16 @@ function initInteractions(ecs)
    local collider, shape, x, y, z = ecs.worldPhysics:raycast(ox, oy, oz, ox + dx, oy + dy, oz + dz)

    if collider then
-      if lovr.headset.isDown(hand, 'trigger') then
-        print("buttondown")
-      end
-      if lovr.headset.wasReleased(hand, 'trigger') or interactionsUpdater['mouse']['released'] then
-        local node = collider:getUserData()
-        interactionsUpdater.selectedBox = collider
-        interactionsUpdater.hitpoint:set(x, y, z)
-        if node.onclick ~= nil then node.onclick(node,collider) end
+      for i, hand in ipairs(lovr.headset.getHands()) do
+        if lovr.headset.isDown(hand, 'trigger') then
+          print("buttondown")
+        end
+        if lovr.headset.wasReleased(hand, 'trigger') or interactionsUpdater['mouse']['released'] then
+          local node = collider:getUserData()
+          interactionsUpdater.selectedBox = collider
+          interactionsUpdater.hitpoint:set(x, y, z)
+          if node.onclick ~= nil then node.onclick(node,collider) end
+        end
      end
    end
    -- reset stuff
@ -216,5 +196,21 @@ function initInteractions(ecs)
  ecs.addSystem( api.world, interactionsUpdater )
 end

-initECS(api.ecs)
+function initCleanups(ecs)
+  local navigateListener = ecs.processingSystem({
+    updatethread = true,
+    filter = ecs.requireAll('URI', ecs.rejectAll('URLResponse') ),
+    onAdd = function(self,obj)
+      -- clear colliders if needed
+      if obj.URI.target ~= nil and obj.URI.target == '_top' then
+        ecs.worldPhysics:destroy()
+        ecs.worldPhysics = lovr.physics.newWorld(0, 0, 0)
+      end
+    end
+  })
+  ecs.addSystem( api.world, navigateListener )
+end
+
 initInteractions(api.ecs)
+initCleanups(api.ecs)
+require("render/model").init(api)
--- a/xurfer/lovr/render/model.lua
+++ b/xurfer/lovr/render/model.lua
@ -0,0 +1,75 @@
+local api = ...
+local modelRenderer
+
+modelRenderer = { 
+
+  -- lovr.draw => ecs.draw (render-logic thread)
+  init = function(api)
+    local ecs = api.ecs
+    api.world.shader = { pbr = false }
+    lovr.shader = lovr.shader or {}
+    lovr.shader['pbr'] = modelRenderer.initShaderPBR()
+
+    renderer = ecs.processingSystem()
+    renderer.filter        = ecs.requireAll('model') 
+    renderer.drawthread = true -- important
+    function renderer:process(obj, pass)
+      if obj.model ~= nil and obj.root ~= nil then 
+        pass:setMaterial()
+        pass:setBlendMode()
+        pass:setFaceCull('none') -- supposed to be defined per-mesh in GLB
+        pass:setCullMode('none')
+        pass:setShader( lovr.shader.pbr )
+        if api.world.environmentMap ~= nil then
+          pass:send('cubemap', api.world.environmentMap)
+        end
+        if api.world.sphericalHarmonics ~= nil then
+          pass:send('sphericalHarmonics', api.world.sphericalHarmonics)
+        end
+        pass:draw(
+          obj['model'], 
+          obj.x or 0, 
+          obj.y or 0,
+          obj.z or 0, 
+          obj.scale or 1, 
+          0, 1, 0, 0, 1)
+      end
+    end
+    ecs.addSystem( api.world, renderer )
+  end,
+
+  initShaderPBR = function()
+    return lovr.graphics.newShader([[
+      vec4 lovrmain() {
+          return DefaultPosition;
+        }
+      ]], [[
+        uniform textureCube cubemap;
+        uniform sphericalHarmonics { vec3 sh[9]; };
+
+        vec4 lovrmain() {
+          Surface surface;
+          initSurface(surface);
+
+          vec3 color = vec3(0);
+          vec3 lightDirection = vec3(-1, -1, -1);
+          vec4 lightColorAndBrightness = vec4(1, 1, 1, 3);
+          float visibility = 1.;
+          color += getLighting(surface, lightDirection, lightColorAndBrightness, visibility);
+          color += getIndirectLighting(surface, cubemap, sh);
+
+          return vec4(color, 1);
+        }
+      ]], {
+        flags = {
+          glow = true,
+          normalMap = true,
+          vertexTangents = false, -- DamagedHelmet doesn't have vertex tangents
+          tonemap = true
+        }
+    })
+  end
+
+}
+
+return modelRenderer
--- a/xurfer/main.lua
+++ b/xurfer/main.lua
@ -9,6 +9,14 @@
 -- ./lovr xurfer https://snips.sh/f/rHFLg-cewi?r=1' -- cube
 -- ./lovr xurfer https://snips.sh/f/_U5-XctEVE?r=1' -- cube, monkey, scene

+local runtime = nil
+
+if lovr ~= nil then 
+  runtime = { path = "lovr", api = lovr }
+elseif love ~= nil then 
+  runtime = { path = "love", api = love };  
+end 
+
 if runtime == nil then 
  package.path = package.path .. ';' .. 'xurfer/?.lua' 
  require('conf') 
@ -32,13 +40,7 @@ api = {
  }
 }

-local runtime
-local runtimepath
-
-if lovr ~= nil then runtime = { path = "lovr", api = lovr }  end 
-if love ~= nil then runtime = { path = "love", api = love }  end 
-
-api = util.merge( api, runtime.api )
+api = util.merge( api, runtime.api ) -- overlay api onto lovr/love-compatible runtime api

 require( runtime.path .. "/main")
  
@ -49,9 +51,7 @@ api.ext.exec('init')

 -- load urls passed on the cli
 foreach( arg, function(k,uri) 
-  foreach( api.protocol, function(name, p)
-    if uri:match("^"..name) then 
-      api.ecs.add( api.world, { URI = { url = uri, method = 'GET', target = '_top' }  })
-    end
-  end)
+  if uri:find(".") and k ~= 0 and k ~= -1 then 
+    api.ecs.add( api.world, { URI = { url = uri, method = 'GET', target = '_top' }  })
+  end
 end)
--- a/xurfer/test.glb
+++ b/xurfer/test.glb
--- a/xurfer/util.lua
+++ b/xurfer/util.lua
@ -69,6 +69,10 @@ function util.dump(value, indent, seen)
  end
 end

+-- error on undefined variable access
+local function err(t,k,v) error("Accessed an undefined variable: " .. tostring(k)) end
+setmetatable(_G, { __index = err })
+
 function util.count(self)
  local i = 0
  if self == nil then return i end
@ -141,6 +145,16 @@ function when(k,v,cb)
  end
 end

+function trace(o)
+  if os.getenv('DEBUG') then 
+    if type(o) == 'table' then 
+      print_r(o) 
+    else
+      print(o)
+    end
+  end
+end
+

 function util.merge(t1,t2)
  local t3 = {}
@ -180,4 +194,23 @@ util.commit = function(world, obj, api)
  end
 end

+util.addHooks = function(fn, cb )
+  return function(...)
+    fn = (fn:gsub("^%l", string.upper)) -- uppercase first char
+    trace("api.ext.exec('before" .. fn .. "')")
+    api.ext.exec( "before" .. fn, ... )
+    local result = cb(...)
+    trace("api.ext.exec('after" .. fn .. "')")
+    api.ext.exec( "after" .. fn, ... )
+    return result
+  end
+end
+
+util.addModuleHooks = function(mod)
+  foreach( mod, function(k,v)
+    mod[k] = util.addHooks(k, v ) 
+  end)
+  return mod
+end
+
 return util