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04 Arnold - Der AI Standard Shader. Multiverse for Autodesk Maya. Multiverse for Maya is a plug-in that encapsulates a complete, procedurally accessible, Alembic pipeline solution for Autodesk Maya.

Multiverse for Autodesk Maya

Multiverse for Maya allows to write, read, display and manipulate Alembic data in a procedurally accessible fashion, to then render with 3delight and Arnold. Alembic data is always read as "packed geometry", streamed to the graphic card, and procedurally rendered: this allows to aggressively reduce RAM usage. In addition to HDF5 and "Ogawa", Multiverse for Maya uses J CUBE's next generation "Git" back-end for Alembic, which provides history, versioning, natural data de-duplication, compression and network protocol mechanisms: this allows to aggressively reduce disk and network usage. Multiverse for Maya is brought to you by J CUBE, the R&D entity of Polygon Pictures, based in Tokyo, Japan. Database Error. CG Animation & VFX Studio in JAPAN. 久々の更新です。

CG Animation & VFX Studio in JAPAN

あれ? これ書いてた中の人、もうコロッサスからいなくなったんだと思ってたよ…というあなた! 半分正解ですwww ここんとこずっとコロッサスのある渋谷から遠く離れたところでVray(仕事で仕方なく…)ばっかり触ってたので、Arnoldのことを忘れかけていたんですが、Solid Angleのジョージさんにお会いしてから、再びブログを再会させることに注力しました。 7月半ばにArnoldの最新版がリリースされていました。 Maya版だと1.1.0.4 Core4.2.0.6です。 MtoA1.0.0が8分08秒 MtoA1.1.0.4が7分54秒 う~ん、ほんの少し速くなっていますね。 さて、今回はArnoldのCameraについてです。 Focal LengthやFilm Offset等、Mayaのパラメータを引き継ぎながら、Camera TypeやExposure等、Arnold専用アトリビュートを設定していきます。

まずDOF効果を設定してみましょう。 頭に焦点(↑)を合わせてみます。 こんどはしっぽに焦点(↑)を合わせてみました。 次に、カメラの種類についても見てみましょう。 これは、普通のパースカメラ(↑)です。 魚眼カメラ(↓)に変えてみましょう。 次は円筒カメラ(↓)です。 円筒状の視野を持つ特殊な表現です。 それから球面カメラ(↓)です。 カメラのレンズが360度視野を持っていることになります。 続いては、カメラの機能ではありませんが、スケール感のあるシーンなので、このシーンを使って空気感を出すためのDepth Fogを与えてみましょう。 Ai Fogはレンダー設定の環境から呼び出します。 カメラから離れるにしたがって白く霞んでいきます。 こちらはVolume Fog(↓)です。 最後にArnold Cameraの特殊なモーションブラーについて。 モーションブラーをONにするだけで、回転体でも問題なく美しいモーションブラー効果が得られます。 このような見え方の異なるモーションブラーを得ることが出来ます。 さらに、Arnoldのモーションブラーにはローリングシャッター効果も簡単に設定できるのだ。 ※ローリングシャッターとは、画像を走査線ごとに上から順に記録するCMOSカメラで高速に動くものを撮影したときに発生する、現実とは異なる形に見えてしまう現象。

Sampling - Arnold for Houdini User Guide. These settings control the sampling quality of the rendered images.

Sampling - Arnold for Houdini User Guide

Increasing the sampling rates reduces the amount of noise in the images, but at the expense of increased rendering time. The actual number of samples is the square of the input number, so in the case of AA samples 32 = 9. This is the same for Diffuse samples, which would be 22 = 4. However Camera samples is a multiplier for Diffuse samples, so the actual number is 9 * 4 = 36. Camera Samples Supersampling control over the number of rays per pixel that will be traced from the camera. Icon Camera samples multiplies Diffuse, Glossy, and light samples after being squared. Diffuse Samples Controls the number of rays fired when computing the reflected indirect-radiance integrated over the hemisphere. When Diffuse samples are more than zero, camera rays intersecting with diffuse surfaces fire indirect diffuse rays. Arnold Volume - Arnold for Houdini User Guide. Volume - Arnold for Maya User Guide. Volume file formats, such as OpenVDB, will allow storage of much larger datasets while being optimized for random access to volume data, which is more efficient for rendering.

Volume - Arnold for Maya User Guide

OpenVDB is an open source C++ library comprising a novel hierarchical data structure and a suite of tools for the efficient storage and manipulation of sparse volumetric data discretized on three-dimensional grids. For information on working with Maya's volumetric fluids, click here. Choose between 'Custom' or 'OpenVDB'.

For custom, you will need a 'Volume Plugin' that will create volumes or load volumes of a specific format. In Data, you will need to assign attributes to that specific 'Volume Plugin'. Custom A procedural can point to ass , obj and ply (Polygon File Format) filetypes. Volume Collector - Arnold for Maya User Guide. The Volume Collector has three color parameters called Scattering, Attenuation, and Emission which are simply used to set the scattering, attenuation and emission coefficients for the volume at the integration sample inside the volume.

Volume Collector - Arnold for Maya User Guide

The (Henyey-Greenstein) Phase parameter is an open interval (-1,+1) where negative values mean backward anisotropic scattering, positive values mean forward anisotropic scattering and zero means isotropic scattering. Be warned that the evaluation of a shader network for volume rendering is much more expensive than for surface shading, because the shader network is called many times per ray, once per ray march sample. So, in a production environment, it's much better to have a single shader doing all the work, instead of relying on potentially expensive inputs. Rendering with the Volume Shader - Arnold for Maya Videos. Rendering Clouds using the Volume Shader - Arnold for Maya Tutorials. This simple tutorial demonstrates how to create a cloud effect using a combination of the Volume Shader with a Maya Cloud 3d texture.

Rendering Clouds using the Volume Shader - Arnold for Maya Tutorials

It is possible to achieve a wide range of cloudy skies using this setup. We will also add a spotlight to replicate sunlight and add some Volumetric Scattering to achieve a 'God ray' effect. To represent the cloud layer, we must first create an object with which we can assign a Volume Shader. Create a sphere or cube and scale it down in the Y axis. Step Size In order to render the mesh as a volume you must do the following. Icon The step size has a fixed size, therefore, the larger the container the more steps will be taken and the longer it will take to render. The images below show the difference in render times when using Step Size. Assign an Ai Standard material to the sphere and select its Shading Group node.Create a Volume Collector node and connect it to the Volume material attribute of the Ai Standard's Shading Group node as in the image below.

OpenVDB Viewer Node for Maya (plugin) Milo-green/openVDBViewerMayaNode.