28 research outputs found
Tree-Structured Shading Decomposition
We study inferring a tree-structured representation from a single image for
object shading. Prior work typically uses the parametric or measured
representation to model shading, which is neither interpretable nor easily
editable. We propose using the shade tree representation, which combines basic
shading nodes and compositing methods to factorize object surface shading. The
shade tree representation enables novice users who are unfamiliar with the
physical shading process to edit object shading in an efficient and intuitive
manner. A main challenge in inferring the shade tree is that the inference
problem involves both the discrete tree structure and the continuous parameters
of the tree nodes. We propose a hybrid approach to address this issue. We
introduce an auto-regressive inference model to generate a rough estimation of
the tree structure and node parameters, and then we fine-tune the inferred
shade tree through an optimization algorithm. We show experiments on synthetic
images, captured reflectance, real images, and non-realistic vector drawings,
allowing downstream applications such as material editing, vectorized shading,
and relighting. Project website: https://chen-geng.com/inv-shade-treesComment: Accepted at ICCV 2023. Project website:
https://chen-geng.com/inv-shade-tree
Spatial Reconstruction of Biological Trees from Point Cloud
Trees are complex systems in nature whose topology and geometry ar
Woodification of polygonal meshes
An evolving polygonal mesh based on stem\u27s tree growth coupled with a physical simulation of bark\u27s cracking is presented. This process is denominated woodification. Whereas previous approaches use a fixed resolution voxel grid, woodification is built on the deformable simplicial complex representation, which robustly simulates growth with adaptive subdivision. The approach allows any meshed object to be grown and textured. Features, such as interaction with obstacles, attributes interpolation, and sketching tools, are added to provide control during the woodifible process
Generación procedural de variaciones en modelos 3D
El problema de partida de este proyecto es el de trasladar al mundo virtual la variabilidad que presentan los objetos del mundo real. Esta variabilidad juega un papel fundamental en la creación de escenas realistas, especialmente en aquellas que incluyen múltiples instancias de un mismo objeto (un bosque, un rebaño, una muchedumbre...). Sin embargo, tratar de capturar esta diversidad de forma manual es un proceso costoso tanto en tiempo de desarrollo como en espacio de memoria.
Este proyecto busca solventar estos dos inconvenientes mediante el uso de técnicas procedurales. Concretamente, se ha desarrollado un sistema capaz de generar variaciones de un modelo 3D de forma automática. Como generalizar el sistema a todo tipo de modelos excede las posibilidades de este proyecto, se ha decidido centrar el trabajo en la generación de variaciones de caballos. Estas variaciones afectan tanto a la textura como a la forma del modelo utilizado.
El sistema ha sido implementado en dos entornos diferentes. La primera implementación utiliza WebGL para llevar las funcionalidades del sistema a aplicaciones de gráficos 3D en la web. La segunda está integrada en Unity, un motor gráfico multiplataforma orientado al desarrollo de videojuegos