3D Plants Modeling

Reporter: Zeng Lanling Sep. 17,2008

Floral Diagrams and Inflorescences: Interactive Flower Modeling Using Botanical Structural Constraints Takashi Ijiri (The University of Tokyo), Shigeru Owada (The

University of Tokyo and Sony CSL), Makoto Okabe, (The University of Tokyo), Takeo Igarashi (The University of Tokyo and JST/PRESTO) siggraph2005

Seamless Integration of Initial Sketching and Subsequent Detail Editing in Flower Modeling

Takashi Ijiri (The University of Tokyo), Shigeru Owada (The University of Tokyo and Sony CSL), Takeo Igarashi (The University of Tokyo and JST/PRESTO) Eurographics2006

Inhibition Fields for Phyllotactic Pattern Formation: a Simulation Study Richard S. Smith (Univercity of Calgery), Cirs Kuhlemeler (University

of Bern), Przemyslaw prusikiewicz (Univercity of Calgery) 2006 NRC Canada

Floral diagrams and inflorescences : Interactive

flower modeling using botanical structural

constraintsTakashi Ijiri (The University of Tokyo)

Shigeru Owada (Sony CS Laboratories Inc.)

Makoto Okabe (The University of Tokyo)

Takeo Igarashi (The University of Tokyo, PRESTO/JST)

Contribution• Interaction techniques

– A specific system to model flowers quickly and easily– Provide structural information of flowers developed by

botanists : floral diagrams & inflorescences• Separating structural editing and geometry editing

– Provide sketching interfaces for user convenience

Notions• Floral diagram

– An iconic description of a flower’s structural characteristics

– To design individual flowers

• Inflorescence– A branch with multiple flowers and its branching

pattern represented in a pictorial form– To design many flowers

Notions

Floral diagram Inflorescence

Floral Diagram

Pi : pistil : 雌蕊St : stamen : 雄蕊Pe : petal : 花瓣O : ovary : 子房Se : sepal : 萼片

Bra : bract : 苞叶R : floral receptacle : 花托A : axis

Up : petal connate to petal :

Sp : sepal adnate to stamen :

Inflorescence

• Indeterminate : lower ones bloom first and higher ones follow– (A) raceme( 总状花序 ), (B) corymb （伞状花序）

• Determinate : top or central first, lower or lateral follow– (C) dichasium （二歧聚伞花序） , (D) drepanium （镰状聚伞花序）

• Compound : mixture– (E) compounded raceme

(A) (B) (C) (D) (E)

Overview

Floral Diagram Editor

(a) Edior (b) Brassica Rapa (c) Ranunculus acris

Floral Component Edit

sketch to 3D model

transform along center vein

globaltransform

localtransform

Inflorescence Editor

Result I

Result II

Result III

Result IV

Seamless Integration of Initial Sketching and Subsequent Detail

Editing in Flower Modeling

Takashi Ijiri (The University of Tokyo)

Shigeru Owada (Sony CS Laboratories Inc.)

Takeo Igarashi (The University of Tokyo, PRESTO/JST)

Overview of the modeling process

Initial sketch as hierarchical billboards

Component representation

Main edit window and an overview window

Construction of an initial sketch

Transformation of the sketch into a 3D model

• One is to create a new 3D component on the billboard.

• The other method reuse existing 3D components from the component library.

Creating a new components

If the billboard type is a branch, when the user presses“create 3D component” button, the system generates a generalized cylinder along the skeleton of the billboard. The user then specifies its radius, color, and texture using standard GUIs.

Creating a new components

Construction of a leaf. (a) A billboard is transformed into a leaf. (b) The system presents a curved blue canvas. (c) On which the user creates a leaf by drawing two outlines . (d) The user can also modify the shape by drawing

modifying strokes (d).

Creating a new components

Construction of a flower. (a) A billboard is transformed into a flower. (b) The system generates a floral receptacle and presents its diagram (c). The user then creates billboards or 3D components and arranges them on the receptacle (d), (e).

Reusing a 3D component

Billboard replacement. The user clicks to select a component (a) and target billboards (b). The system then replaces billboards with the specified component (c). Users may also double-click to select all sibling billboards (d).

Reusing a 3D component

Placing 3D components. The user selects a source (a) from the library and draws a skeleton stroke (b). The system then places the object (c). Examples of more complicated objects are shown in (d) and (e).

Reusing a 3D component

Fitting a leaf object to the target skeleton

Skeleton-based deformation of 3D components

Skeleton-based deformation. The user draws the stroke shown in red (a) and then the system deforms the target stem (b) so that the stem’s skeleton fits the stroke on the screen (c).

Skeleton-based deformation of 3D components

Fitting the skeleton to the user-drawn stroke

Result

Result

Richard S. Smith (The University of Calgary)

Ris Kuhlemeier (The University of Berne)

Przemyslaw Prusinkiewicz (The University of Calgary)

Inhibition Fields for Phyllotactic Pattern Formation: a Simulation

Study

Main idea

The postulate that existing primordia

inhibit the formation of new primordia

nearby.

Objective• The model can generate a wide variety of

phyllotactic patterns

• Patterns can start in an empty peripheral zone or from one or two cotyledons

• The model can capture transitions in phyllotaxis, such as the often-observed transition from decussate to spiral patterns

• The patterns can be initiated an propagated in a robust manner

Phyllotactic patterns

Model

Model

Diagram of inhibition

Diagram of inhibition

Inhibition threshold

Inhibition threshold

Inhibition threshold(128)

Example(Arabidopsis)

Two inhibition functions

Two inhibition functions

Other method

Other method

Other method

Thank you!