Class4

Class4 - Class 4. Spaces needed to coordinate modeling,...

Info iconThis preview shows pages 1–6. Sign up to view the full content.

View Full Document Right Arrow Icon
Class 4. Spaces needed to coordinate modeling, animation, viewing, and rendering Ulrich Neumann CS580 (Computer Graphics Rendering)
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Spaces : model, world, image (camera), perspective (NDC), screen screen is pixel coords like FB in HW1 (Right-handed coords) perspective is NDC (x, y = [-1,1], z = [0,1]) (LHC) image has center of projection plane at (0,0,0), looking along +z (LHC) world has all some origin/axis as reference for object locations (LHC) model has coord frame(s) of its own (LHC) All are left-handed except for screen, which is right-handed x y z-in x y z-in
Background image of page 2
Transforms : screen X sp perspective (NDC) X pi image X iw world X wm model Xforms are between spaces - Renderer maintains the complete transformation X sm Application/animation controls each transform for different purposes X wm object positions (per frame or per instance) X iw camera motion/external parameters (per frame) X pi camera FOV (focal length, zoom) internal parameters (per frame) X sp screen or frame-buffer mapping (per session)
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Managing Xforms Use one of more stack structures that allow push/pop operations. Push in sequence from screen to model. Pop as many as needed in reverse order to allow push of modified matrix. Complete pushes before rendering next frame. Full stack must transform models to screen Xsm Let stack accumulate transforms, rather than just storing them Push A Top of stack = (A) Push B Top of stack = (AB) Push C Top of stack = (ABC) Pop Top of stack = (AB) Push D Top of stack = (ABD)
Background image of page 4
How to move camera Change X iw to produces a camera change Build new X iw (show how in later slide) Pop to remove X wm from full X sm stack – leaves X sw on stack Pop to remove X iw from X sm
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 6
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/22/2010 for the course CS 580 at USC.

Page1 / 17

Class4 - Class 4. Spaces needed to coordinate modeling,...

This preview shows document pages 1 - 6. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online