RENDERING, CAMERAS & LIGHTING CGDD 4113 Jeff Chastine RENDERING • The process of converting your scene into a 2D image • For gaming, we don’t care about it that much (but still important) • Click on a View (the header) and then use menus and shelf • For this class, use standard menu bar • Open rendering view • Render Single Frame* • IPR Rendering • Render Settings* • After rendering, you have the option to save the image (File->Save Image) COMMON SETTINGS • File Output • Prefix • Image format • Resolution (e.g. 640x480, 72 dpi) • Frame range (for animations) • Camera (front, side, persp) • Aspect ration (HD) MAYA SOFTWARE SETTINGS CAMERA SETTINGS • In each view, there’s a camera icon • Can set options like: • Depth of field • Background color • Angle of view • Focal length • Near/Far clip plane CAMERA SETTINGS IMAGE PLANES • Using an image as the background color • Image always faces the camera (orthogonal) • Can animate it, but doesn’t move if camera turns • Instead use a Skybox (or Sky Dome) LIGHTING • Several kinds of lights – hardest part of realism! • Default* – if no other lights, this one’s there (to the upper-left of camera) • Ambient – only affects ambient component of material • Directional light - parallel rays come from infinitely far away • Point* - a lamp • Spotlight* - a spotlight (duh!) • Area* – a rectangular light is the source (not just a point). Soft edged shadows • Volume – advanced. We won’t be using it here. • Global Illumination (Radiosity) – algorithm, not light. Patch-based. Mental Ray only. • Shadows – must turn them on per light and in render settings! * Attenuated (falls off with distance). Typically 1/d^2 http://krypton.fhda.edu/~bpuckett/gallery/doit_urself/Maya/Lights_and_Lighting DEFAULT LIGHT (WITH RAYTRACING AND SHADOWS TURNED ON) AMBIENT LIGHT (WITH INTENSITY AT 1.000 TO DEMONSTRATE IT – SHADOWS OFF) DIRECTIONAL LIGHT • Has two parts (position and direction) • Separate with the ‘T’ key DIRECTIONAL LIGHT (RAYTRACING, SHADOWS ON) POINT LIGHT SPOT LIGHT (2 PARTS) (PENUMBRA =5.0, CONE ANGLE=50.0, NO DECAY) AREA LIGHT (2 PARTS) ABOUT SHADOWS • Two common kinds of shadows • Raytrace • Takes longer • Usually gives hard edges • Is exact • Shadow maps • Usually faster • Must specify resolution (default 512, which is bad) • Gives softer edges • Edges can be jagged ABOUT SHADOWS 512 8192