WYSIWYG NPR: Drawing Strokes Directly on 3D Models Paper by: Robert D. Kalnins, Lee Markosian, Barbara J. Meier, Michael A. Kowalski, Joseph C. Lee, Philip L. Davidson, Matthew Webb, John F. Hughes and Adam Finkelstein. Presentation by: Nathan F. Cantelmo

Table of Contents ● WYSIWYG NPR Overview ● Interface Descriptions ● Rendering System & Shaders ● Stroke Styles & Features ● Hatching & LOD Methods ● Summary & Conclusions ● Points for Discussion

WYSIWYG NPR Overview ● What is WYSIWYG NPR? ● How does it work? ● Who should use it? ● What purpose does it serve?

Interface Descriptions ● Tablet, mouse, or keyboard used for input ● Three editing modes: ● Line editing mode ● Hatching editing mode ● Basecoat editing mode

Line Editing Mode

Hatching Editing Mode

Basecoat Editing Mode

Rendering System & Shaders ● Triangle mesh used for models ● Mesh divided into patches ● Each patch rendered by four shaders: ● Background and base coat shader ● Stroke formation shader ● Stroke visibility shader ● Media simulation shader

Rendering System & Shaders

Stroke Styles & Features ● Four types of strokes: ● Decal strokes ● Crease strokes ● Silhouette strokes ● Hatching strokes

Stroke Styles & Features

Hatching & LOD Methods ● Two types of hatching: ● Fixed hatching ● Mobile hatching ● Two types of LOD control: ● Structured hatching ● Free hatching

Hatching & LOD Methods

Summary & Conclusions ● Strengths of WYSIWYG NPR ● Weaknesses of the system ● Continuing work: ● Jot ● Coherent Stylized Silhouettes

Points for Discussion ● How might the stroke visibility algorithm be improved? ● Could individual silhouettes be annotated uniquely? ● What other, unmentioned shortcomings exist? ● Other questions, comments, etc.