Plant models faithful to botanical structure and development

ACM SIGGRAPH Computer Graphics, 1988

Some very impressive results have been obtained in the past few years in plants and trees image synthesis. Some algorithms are largely based on the irregularity and fuzziness of the objects, and use fractals, graftals or particle systems. Others focus on the branching pattern of the trees with emphasis on morphology. Our concern here is the faithfulness of the models to the botanical nature of trees and plants. We present a model which integrates botanical knowledge of the architecture of the trees: how they grow, how they occupy space, where and how leaves,flowers or fruits are located, etc. The very first interest of the model we propose is its great richness: the same procedural methods can produce "plants" as different as weeping willows, fir trees, cedar trees, frangipani trees, poplars, pine trees, wild cherry trees, herbs, etc. Another very important benefit one can deriw from the model is the integration of time which enables viewing the aging of a tree (possibility to get different pictures of the same tree at different ages, accurate simulation of the death of leaves and branches for example). The ease to integrate physical parameters such as wind, the incidence of factors such as insects attacks, use of fertilizers, plantation density, and so on makes it a useful tool for agronomy or botany.

Plants are essential elements of virtual worlds to get pleasant and realistic 3D environments. Even if mature computer vision techniques allow the reconstruction of challenging 3D objects from images, due to high complexity of plant topology, dedicated methods for generating 3D plant models must be devised. We propose an analysis-by-synthesis method which generates 3D models of a plant from both images and a priori knowledge of the plant species. Our method is based on a skeletonisation algorithm which allows to generate a possible skeleton from a foliage segmentation. Then, a 3D genera-tive model, based on a parametric model of branching systems that takes into account botanical knowledge is built. This method extends previous works by constraining the resulting skeleton to follow hierarchical organisation of natural branching structure. A first instance of a 3D model is generated. A reprojection of this model is compared with the original image. Then, we show that selecting the model from multiple proposals for the main branching structure of the plant and for the foliage improves the quality of the generated 3D model. Varying parameter values of the generative model, we produce a series of candidate models. A criterion based on comparing 3D virtual plant reprojection with original image selects the best model. Realistic results obtained on different species of plants illustrate the performance of the proposed method. Fig. 1. On the left, an original image of a vine plant before and after a metric rec-tification. In the middle, a possible architecture of the branching extracted with our skeletonisation method. At the right, a 3D model of this plant.

Lecture Notes in Computer Science, 2010

We introduce in this paper an interface for botanical tree modeling that allows the user to sketch a tree, and then to automatically reproduce it at various stages of 'growth'. The technique works by first inferring as best as possible the L-System growth rule that represent the tree model drawn by the user. The user can then reproduce the tree model by drawing a growth stroke. The growth stroke indicates the shape of the main axis, and the height up to which the tree should be grown, and determines the number of iterations of applications of the L-system rule. We show in this paper how the technique can be used as a simple yet effective way to produce variants of a tree structure.

2006

This paper gives an overview of computer graphics representations of trees commonly used for the rendering of complex scene of vegetation. Looking for the right compromise between realism and efficiency has lead researchers to consider various types of geometrical plant models with different types of complexity. To achieve realist plant model, a complex structure of plant with full details is

2006

This paper gives an overview of computer graphics representations of trees commonly used for the rendering of complex scene of vegetation. Looking for the right compromise between realism and efficiency has lead researchers to consider various types of geometrical plant models with different types of complexity. To achieve realist plant model, a complex structure of plant with full details is generally considered. In contrast, to promote efficiency, other approaches summarize plant geometry with few primitives allowing rapid rendering. Finally, to find a good compromise, structures with adaptive complexity are defined. Theses different types of representations and the ways to use them are presented, classified and discussed. The proposed classification principles rely on the type of structural details used in the plants representations. Characterization of all these methods is completed with various additional criteria including rendering primitive type, distance validity, interacti...

A new semi-automatic method for determining parameters for L-based plant modeling systems is introduced. It is shown that many of the parameters necessary to create realistic plants can be extracted semi-automatically from photographs of real plants. By replacing numerical parameters with a more intuitive set of graphical modeling primitives, it is possible to significantly speed up the design process of complex three-dimensional shapes, such as plants. We also explain how to add small scale detail and natural transitions to skeletal models of plants to further improve the design process.

IEEE Transactions on Visualization and Computer Graphics, 2020

In this paper, we describe a novel procedural modeling technique for generating realistic plant models from multi-view photographs. The realism is enhanced via visual and spatial information acquired from images. In contrast to previous approaches that heavily rely on user interaction to segment plants or recover branches in images, our method automatically estimates an accurate depth map of each image and extracts a 3D dense point cloud by exploiting an efficient stereophotogrammetry approach. Taking this point cloud as a soft constraint, we fit a parametric plant representation to simulate the plant growth progress. In this way, we are able to synthesize parametric plant models from real data provided by photos and 3D point clouds. We demonstrate the robustness of the proposed approach by modeling various plants with complex branching structures and significant self-occlusions. We also demonstrate that the proposed framework can be used to reconstruct groundcovering plants, such as bushes and shrubs which have been given little attention in the literature. The effectiveness of our approach is validated by visually and quantitatively comparing with the state-of-the-art approaches.

Each tree is unique because of the physical environment it experiences over the course of its life. Environmental factors shape a tree within the bounds of its genotype. Only by modeling the environmental influences can we create realistic models of trees. To this end, we constructed a structural simulation that calculates the mass of each branch of the tree to emulate the mechanisms the tree uses to balance its weight, and that estimates the photosynthesis return of the leaves to simulate phototropism. Our effort is motivated by a desire to construct a predictive tool that can be used by both those in computer graphics and forest management, with applications in image synthesis, dendrochronology, mensuration and the simulation of forest succession.

: A 3D model of a tree is imported (a). Our system automatically computes a dynamic model that is able to react interactively to environmental changes such as trees growing together (b) or when obstacles are moved towards the tree and cast shadow on it (c)-(e).

Computer Graphics Forum, 2004

A method is proposed for photo-realistic modeling and visualization of a growing tree. Recent visualization methods have focused on producing smoothly blending branching structures, however, these methods fail to account for the inclusion of non-smooth features such as branch bark ridges and bud scale scars. These features constitute an important visual aspect of a living tree, and are also observed to vary over time. The proposed method incorporates these features by using an hierarchical implicit modeling system, which provides a variety of tools for combining surface components in both smooth and non smooth configurations. A procedural interface to this system supports the use of inverse modeling, which is a global-to-local methodology, where the local properties of plant organs are described in terms of their global position within the tree architecture. Inverse modeling is used to define both the tree structure at any time, and a continuous developmental sequence for the tree from a seedling. These techniques provide an intuitive paradigm for the definition of complex tree growth sequences and their subsequent visualization, based solely on observed phenomena. Thus, a key advantage is that they do not require any knowledge of, or simulation of, the underlying biological processes.