a free open source modelling/rendering software · a free open source modelling/rendering software....

A free open source modelling/rendering software

RenderingIn short, rendering is the process of generating an image from a model or set of models in a scene file.

Different styles ie. Photorealistic(Cycles), and Cartoon (Freestyle)

ModellingCreating objects by adding and manipulating faces

Convention: To use quads (face with 4 edges and 4 vertices) connected to other faces

Blender allows for individual vertex control as opposed to CAD software which uses geometric modelling

Basis of CG (Computer Generated)CG or CGI is everywhere (Movies/TV uses it extensively. Pretty much any car chase scene has to have CG as it is more cost effective and is just as good)

Catalogue magazines eg. IKEA catalogues have 75% of their showcased items as renderings

Tech product Ads usually showcase the object floating around with sleek shine (eg. IPhone Ads)

Why Blender?

Free and open source

Countless online tutorials (most free, there are online courses that cost money)

It is just as good as other programs that cost an arm and a leg

Blender is much more than just a modelling/rendering program.

Modelling (3D printing and Rendering)

Sculpting

Simulations (Fluids, Particles, Rigidbodies, Smoke)

And Lots More!

Animation

Video Editing

Compositing

Motion Tracking and Green Screen Implementation

Hair and Fur Dynamics

What have I done?

Created models for machining purposes such as plexiglass cutouts

3D printed components for rigs

Recreated rigs in Blender to render images as figures for posters, publications and presentations.

Created animations showcasing rigs

Modelling and Rendering Process

Renderings of Homecages and Rigs

Benefits of RenderingRendering a scene allows you to capture an image or angle that would otherwise be impossible to get.

It can provide snapshots of a system at different states without interfering (eg. mice in homecages pulling levers, dark chambers, etc.)

Using a photorealistic approach, viewers are given a detailed view of the system while the creator has full control of lighting and camera placement

Photorealism

The attempt of making the generated renderings resemble the real world.

Uses PBR materials (Physically Based Rendering) which takes into consideration properties that can describe an object in the real world.

Color (Texture Map), Roughness, Metallic Value, IOR (Index of Refraction) etc

Many lists online on property values of many materials (metals, liquids, plastics, glass)

How does it actually calculate the pixel colour value?Blender Cycles uses a method called Path Tracing to calculate colour

Algorithm integrates over all the luminance at a single point on a surface and is then reduced by a surface reflectance function (BRDF)

It is then repeated for every pixel in the camera resolution

Path Tracing by nature simulates soft shadows, depth of field, motion blur, caustics, ambient occlusion, and indirect lighting

Recursive Path Tracing

Ray Casting from Camera to Scene (Primary Rays)

On contact with surface, Shadow Rays are castPrimary Ray

Shadow Ray

If surface is metallic, cast reflective rays at incident angle

Primary Ray

Shadow Ray

Reflection Ray

If reflective ray hits, repeat as primary rayPrimary Ray

Shadow Ray

Reflection Ray

If surface is translucent use index of refraction to cast ray

Primary Ray

Shadow Ray

Reflection Ray

Refractive Ray

Turner Whitted first image produced using path tracing. Took 72 minutes to render yet now only takes 1/60th of a second thanks to Moore’s Law

Bad things about BlenderA lot of people say UI is very difficult to learn

Learning curve is steep but very rewarding

Blender’s view control differs from industry standard

Long time between major updates/feature add-ons

Before Blender demo, any questions?