Files
filament/docs/webgl/tutorial_suzanne.html
Mathias Agopian 9474798c75 remove anamorphic bloom feature
This features didn't work well, had a lot of artifacts and generally
wasn't very useful. This kind of effect should be accomplished
differently.

This is an API break because BloomOptions::anamorphism has been removed.
2023-09-18 16:09:21 -07:00

257 lines
39 KiB
HTML

<!DOCTYPE html>
<html lang="en"><head>
<link href="https://google.github.io/filament/favicon.png" rel="icon" type="image/x-icon" />
<link href="https://fonts.googleapis.com/css?family=Open+Sans:300,400,600,700|Tangerine:700|Inconsolata" rel="stylesheet">
<link href="main.css" rel="stylesheet" type="text/css">
</head>
<body class="verbiage">
<div class="demo_frame"><iframe src="demo_suzanne.html"></iframe><a href="demo_suzanne.html">&#x1F517;</a></div>
<p>This tutorial will describe how to create the <strong>suzanne</strong> demo, introducing you to compressed
textures, mipmap generation, asynchronous texture loading, and trackball rotation.</p>
<p>Much like the <a href="tutorial_redball.html">previous tutorial</a>, you&#x27;ll need to use the command-line tools that can be found in
the appropriate <a href="//github.com/google/filament/releases">Filament release</a> for your development machine. In addition to <code>matc</code> and <code>cmgen</code>,
we&#x27;ll also be using <code>filamesh</code> and <code>mipgen</code>.</p>
<h2>Create filamesh file</h2>
<p>Filament does not have an asset loading system, but it does provide a binary mesh format
called <code>filamesh</code> for simple use cases. Let&#x27;s create a compressed filamesh file for suzanne by
converting <a href="https://github.com/google/filament/blob/main/assets/models/monkey/monkey.obj">this OBJ file</a>:</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>filamesh --compress monkey.obj suzanne.filamesh
</pre></div>
<h2>Create mipmapped textures</h2>
<p>Next, let&#x27;s create mipmapped KTX files using filament&#x27;s <code>mipgen</code> tool. We&#x27;ll create compressed and
non-compressed variants for each texture, since not all platforms support the same compression
formats. First copy over the PNG files from the <a href="https://github.com/google/filament/blob/main/assets/models/monkey">monkey folder</a>, then do:</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic"># Create mipmaps for base color</span>
mipgen albedo.png albedo.ktx2
mipgen --compression<span style="color: #666666">=</span>uastc albedo.png albedo.ktx2
<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the normal map and a compressed variant.</span>
mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear normal.png normal.ktx
mipgen --strip-alpha --kernel<span style="color: #666666">=</span>NORMALS --linear --compression<span style="color: #666666">=</span>uastc_normals <span style="color: #AA5D1F; font-weight: bold">\</span>
normal.png normal.ktx2
<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component roughness map and a compressed variant.</span>
mipgen --grayscale roughness.png roughness.ktx
mipgen --grayscale --compression<span style="color: #666666">=</span>uastc roughness.png roughness.ktx2
<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component metallic map and a compressed variant.</span>
mipgen --grayscale metallic.png metallic.ktx
mipgen --grayscale --compression<span style="color: #666666">=</span>uastc metallic.png metallic.ktx2
<span style="color: #3D7B7B; font-style: italic"># Create mipmaps for the single-component occlusion map and a compressed variant.</span>
mipgen --grayscale ao.png ao.ktx
mipgen --grayscale --compression<span style="color: #666666">=</span>uastc ao.png ao.ktx2
</pre></div>
<p>For more information on mipgen&#x27;s arguments and supported formats, do <code>mipgen --help</code>.</p>
<p>In a production setting, you&#x27;d want to invoke these commands with a script or build system.</p>
<h2>Bake environment map</h2>
<p>Much like the <a href="tutorial_redball.html">previous tutorial</a> we need to use Filament&#x27;s <code>cmgen</code> tool to produce cubemap files.</p>
<p>Download <a href="//github.com/google/filament/blob/main/third_party/environments/venetian_crossroads_2k.hdr">venetian_crossroads_2k.hdr</a>, then invoke the following commands in your terminal.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=64</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
<span style="color: #008000">cd</span> venetian* ; mv venetian*_ibl.ktx venetian_crossroads_2k_skybox_tiny.ktx ; <span style="color: #008000">cd</span> -
cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
cmgen -x . --format<span style="color: #666666">=</span>ktx --size<span style="color: #666666">=256</span> --extract-blur<span style="color: #666666">=0</span>.1 venetian_crossroads_2k.hdr
</pre></div>
<h2>Define textured material</h2>
<p>You might recall the <code>filamat</code> file we generated in the previous tutorial for red plastic. For this
demo, we&#x27;ll create a material that uses textures for several parameters.</p>
<p>Create the following text file and call it <code>textured.mat</code>. Note that our material definition now
requires a <code>uv0</code> attribute.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>material {
name : textured,
requires : [ uv0 ],
shadingModel : lit,
parameters : [
{ type : sampler2d, name : albedo },
{ type : sampler2d, name : roughness },
{ type : sampler2d, name : metallic },
{ type : float, name : clearCoat },
{ type : sampler2d, name : normal },
{ type : sampler2d, name : ao }
],
}
fragment {
void material(inout MaterialInputs material) {
material.normal = texture(materialParams_normal, getUV0()).xyz * 2.0 - 1.0;
prepareMaterial(material);
material.baseColor = texture(materialParams_albedo, getUV0());
material.roughness = texture(materialParams_roughness, getUV0()).r;
material.metallic = texture(materialParams_metallic, getUV0()).r;
material.clearCoat = materialParams.clearCoat;
material.ambientOcclusion = texture(materialParams_ao, getUV0()).r;
}
}
</pre></div>
<p>Next, invoke <code>matc</code> as follows.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>matc -a opengl -p mobile -o textured.filamat textured.mat
</pre></div>
<p>You should now have a material archive in your working directory. For the suzanne asset, the normal
map adds scratches, the albedo map paints the eyes white, and so on. For more information on
materials, consult the official document describing the <a href="https://google.github.io/filament/Materials.md.html">Filament Material System</a>.</p>
<h2>Create app skeleton</h2>
<p>Create a text file called <code>suzanne.html</code> and copy over the HTML that we used in the <a href="tutorial_redball.html">previous
tutorial</a>. Change the last script tag from <code>redball.js</code> to <code>suzanne.js</code>. Next, create <code>suzanne.js</code>
with the following content.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #3D7B7B; font-style: italic">// TODO: declare asset URLs</span><span style="color: #bbbbbb"></span>
Filament.init([<span style="color: #bbbbbb"> </span>filamat_url,<span style="color: #bbbbbb"> </span>filamesh_url,<span style="color: #bbbbbb"> </span>sky_small_url,<span style="color: #bbbbbb"> </span>ibl_url<span style="color: #bbbbbb"> </span>],<span style="color: #bbbbbb"> </span>()<span style="color: #bbbbbb"> </span>=&gt;<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.app<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>App(<span style="color: #008000">document</span>.getElementsByTagName(<span style="color: #BA2121">&#39;canvas&#39;</span>)[<span style="color: #666666">0</span>]);<span style="color: #bbbbbb"></span>
});<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">class</span><span style="color: #bbbbbb"> </span>App<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">constructor</span>(canvas)<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>canvas;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Engine.create(canvas);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.scene<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createScene();<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>material<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createMaterial(filamat_url);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>material.createInstance();<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamesh<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.loadFilamesh(filamesh_url,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.suzanne<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>filamesh.renderable;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #3D7B7B; font-style: italic">// TODO: create sky box and IBL</span><span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #3D7B7B; font-style: italic">// TODO: initialize gltumble</span><span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #3D7B7B; font-style: italic">// TODO: fetch larger assets</span><span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.swapChain<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSwapChain();<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.renderer<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createRenderer();<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.camera<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createCamera(Filament.EntityManager.get().create());<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createView();<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view.setCamera(<span style="color: #008000; font-weight: bold">this</span>.camera);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view.setScene(<span style="color: #008000; font-weight: bold">this</span>.scene);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.render<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.render.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize.bind(<span style="color: #008000; font-weight: bold">this</span>);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.addEventListener(<span style="color: #BA2121">&#39;resize&#39;</span>,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>eye<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">4</span>],<span style="color: #bbbbbb"> </span>center<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>],<span style="color: #bbbbbb"> </span>up<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>[<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">1</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>];<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.camera.lookAt(eye,<span style="color: #bbbbbb"> </span>center,<span style="color: #bbbbbb"> </span>up);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.resize();<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>render()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #3D7B7B; font-style: italic">// TODO: apply gltumble matrix</span><span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.renderer.render(<span style="color: #008000; font-weight: bold">this</span>.swapChain,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.requestAnimationFrame(<span style="color: #008000; font-weight: bold">this</span>.render);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>resize()<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>dpr<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.devicePixelRatio;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.width<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerWidth<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.canvas.height<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000">window</span>.innerHeight<span style="color: #bbbbbb"> </span><span style="color: #666666">*</span><span style="color: #bbbbbb"> </span>dpr;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.view.setViewport([<span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">0</span>,<span style="color: #bbbbbb"> </span>width,<span style="color: #bbbbbb"> </span>height]);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>aspect<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>width<span style="color: #bbbbbb"> </span><span style="color: #666666">/</span><span style="color: #bbbbbb"> </span>height;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>Fov<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.Camera$Fov,<span style="color: #bbbbbb"> </span>fov<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>aspect<span style="color: #bbbbbb"> </span><span style="color: #666666">&lt;</span><span style="color: #bbbbbb"> </span><span style="color: #666666">1</span><span style="color: #bbbbbb"> </span><span style="color: #666666">?</span><span style="color: #bbbbbb"> </span>Fov.HORIZONTAL<span style="color: #bbbbbb"> </span><span style="color: #666666">:</span><span style="color: #bbbbbb"> </span>Fov.VERTICAL;<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.camera.setProjectionFov(<span style="color: #666666">45</span>,<span style="color: #bbbbbb"> </span>aspect,<span style="color: #bbbbbb"> </span><span style="color: #666666">1.0</span>,<span style="color: #bbbbbb"> </span><span style="color: #666666">10.0</span>,<span style="color: #bbbbbb"> </span>fov);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>}<span style="color: #bbbbbb"></span>
}<span style="color: #bbbbbb"></span>
</pre></div>
<p>Our app will only require a subset of assets to be present for <code>App</code> construction. We&#x27;ll download
the other assets after construction. By using a progressive loading strategy, we can reduce the
perceived load time.</p>
<p>Next we need to supply the URLs for various assets. This is actually a bit tricky, because different
clients have different capabilities for compressed textures.</p>
<p>To help you download only the texture assets that you need, Filament provides a
<code>getSupportedFormatSuffix</code> function. This takes a space-separated list of desired format types
(<code>etc</code>, <code>s3tc</code>, or <code>astc</code>) that the app developer knows is available from the server. The function
performs an intersection of the <em>desired</em> set with the <em>supported</em> set, then returns an appropriate
string -- which might be empty.</p>
<p>In our case, we know that our web server will have <code>astc</code> and <code>s3tc</code> variants for albedo, and <code>etc</code>
variants for the other textures. The uncompressed variants (empty string) are always available as a
last resort. Go ahead and replace the <strong>declare asset URLs</strong> comment with the following snippet.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>albedo_suffix<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;astc s3tc_srgb&#39;</span>);<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>texture_suffix<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>Filament.getSupportedFormatSuffix(<span style="color: #BA2121">&#39;etc&#39;</span>);<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>environ<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;venetian_crossroads_2k&#39;</span><span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ibl_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_ibl.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sky_small_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox_tiny.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sky_large_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">/</span><span style="color: #A45A77; font-weight: bold">${</span>environ<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">_skybox.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>albedo_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`albedo</span><span style="color: #A45A77; font-weight: bold">${</span>albedo_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ao_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`ao</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>metallic_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`metallic</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>normal_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`normal</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>roughness_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">`roughness</span><span style="color: #A45A77; font-weight: bold">${</span>texture_suffix<span style="color: #A45A77; font-weight: bold">}</span><span style="color: #BA2121">.ktx`</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamat_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;textured.filamat&#39;</span>;<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>filamesh_url<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #BA2121">&#39;suzanne.filamesh&#39;</span>;<span style="color: #bbbbbb"></span>
</pre></div>
<h2>Create skybox and IBL</h2>
<p>Next, let&#x27;s create the low-resolution skybox and IBL in the <code>App</code> constructor.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.skybox<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx1(sky_small_url);<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">this</span>.indirectLight<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createIblFromKtx1(ibl_url);<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">this</span>.indirectLight.setIntensity(<span style="color: #666666">100000</span>);<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">this</span>.scene.setIndirectLight(<span style="color: #008000; font-weight: bold">this</span>.indirectLight);<span style="color: #bbbbbb"></span>
</pre></div>
<p>This allows users to see a reasonable background fairly quickly, before larger assets have finished
loading in.</p>
<h2>Fetch assets asychronously</h2>
<p>Next we&#x27;ll invoke the <code>Filament.fetch</code> function from within the app constructor. This function is
very similar to <code>Filament.init</code>. It takes a list of asset URLs and a callback function that triggers
when the assets have finished downloading.</p>
<p>In our callback, we&#x27;ll make several <code>setTextureParameter</code> calls on the material instance, then we&#x27;ll
recreate the skybox using a higher-resolution texture. As a last step we unhide the renderable that
was created in the app constructor.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>Filament.fetch([sky_large_url,<span style="color: #bbbbbb"> </span>albedo_url,<span style="color: #bbbbbb"> </span>roughness_url,<span style="color: #bbbbbb"> </span>metallic_url,<span style="color: #bbbbbb"> </span>normal_url,<span style="color: #bbbbbb"> </span>ao_url],<span style="color: #bbbbbb"> </span>()<span style="color: #bbbbbb"> </span>=&gt;<span style="color: #bbbbbb"> </span>{<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>albedo<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(albedo_url,<span style="color: #bbbbbb"> </span>{srgb<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">true</span>});<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>roughness<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(roughness_url);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>metallic<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(metallic_url);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>normal<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(normal_url);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>ao<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createTextureFromKtx2(ao_url);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>sampler<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Filament.TextureSampler(<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>Filament.MinFilter.LINEAR_MIPMAP_LINEAR,<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>Filament.MagFilter.LINEAR,<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span>Filament.WrapMode.CLAMP_TO_EDGE);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;albedo&#39;</span>,<span style="color: #bbbbbb"> </span>albedo,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;roughness&#39;</span>,<span style="color: #bbbbbb"> </span>roughness,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;metallic&#39;</span>,<span style="color: #bbbbbb"> </span>metallic,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;normal&#39;</span>,<span style="color: #bbbbbb"> </span>normal,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.matinstance.setTextureParameter(<span style="color: #BA2121">&#39;ao&#39;</span>,<span style="color: #bbbbbb"> </span>ao,<span style="color: #bbbbbb"> </span>sampler);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #3D7B7B; font-style: italic">// Replace low-res skybox with high-res skybox.</span><span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.destroySkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.skybox<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.createSkyFromKtx1(sky_large_url);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.scene.setSkybox(<span style="color: #008000; font-weight: bold">this</span>.skybox);<span style="color: #bbbbbb"></span>
<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.scene.addEntity(<span style="color: #008000; font-weight: bold">this</span>.suzanne);<span style="color: #bbbbbb"></span>
});<span style="color: #bbbbbb"></span>
</pre></div>
<h2>Introduce trackball rotation</h2>
<p>Add the following script tag to your HTML file. This imports a small third-party library that
listens for drag events and computes a rotation matrix.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span>&lt;<span style="color: #008000; font-weight: bold">script</span> <span style="color: #687822">src</span><span style="color: #666666">=</span><span style="color: #BA2121">&quot;//unpkg.com/gltumble&quot;</span>&gt;&lt;/<span style="color: #008000; font-weight: bold">script</span>&gt;
</pre></div>
<p>Next, replace the <strong>initialize gltumble</strong> and <strong>apply gltumble matrix</strong> comments with the following
two code snippets.</p>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">this</span>.trackball<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #AA22FF; font-weight: bold">new</span><span style="color: #bbbbbb"> </span>Trackball(canvas,<span style="color: #bbbbbb"> </span>{startSpin<span style="color: #666666">:</span><span style="color: #bbbbbb"> </span><span style="color: #666666">0.035</span>});<span style="color: #bbbbbb"></span>
</pre></div>
<div class="highlight" style="background: #f8f8f8"><pre style="line-height: 125%;"><span></span><span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>tcm<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.engine.getTransformManager();<span style="color: #bbbbbb"></span>
<span style="color: #008000; font-weight: bold">const</span><span style="color: #bbbbbb"> </span>inst<span style="color: #bbbbbb"> </span><span style="color: #666666">=</span><span style="color: #bbbbbb"> </span>tcm.getInstance(<span style="color: #008000; font-weight: bold">this</span>.suzanne);<span style="color: #bbbbbb"></span>
tcm.setTransform(inst,<span style="color: #bbbbbb"> </span><span style="color: #008000; font-weight: bold">this</span>.trackball.getMatrix());<span style="color: #bbbbbb"></span>
inst.<span style="color: #AA22FF; font-weight: bold">delete</span>();<span style="color: #bbbbbb"></span>
</pre></div>
<p>That&#x27;s it, we now have a fast-loading interactive demo. The complete JavaScript file is available
<a href="tutorial_suzanne.js">here</a>.</p>
</body>
</html>