The images produced by means ofcomputers have invaded our daily lives. One has but to see the "identification logos" of most television broadcasts or some advenisement "spots" to be convinced of this. This proves that the synthesis ofimages has reached maturity. The progress that has been made in the last few years allows one to predict the use ofrealistic illustrations in more and more domains ofapplication. It is thus understandable that more and more people seek to understand how these images are produced. Such a person may be an amateur who likes to understand in a general way the processing involved, or he may be a computer scientist who wants to develop some new application using graphics procedures. This book by Michel Bret meets these desires by giving a complete overview of the techniques of image synthesis by computer. The different stages of the creation of a numerical image are explained in detail, and they are accompanied by descriptions of the most modem methods. Thus the geometrical models that are described go from those with plane polygonal facets, via surfaces of all types, to systems of panicles. Visualization is treated in complete detail, and due attention is given to all the various roads that lead to a realistic image: simple projections on the basis of wire-frame models, the elimination of hidden pans, and fmally the modelling oflight and its effects.

Table of Contents:
1. Images.- 1.1. Images and communication.- 1.1.1. Speaking.- 1.1.2. Writing.- 1.1.3. Images.- 1.1.4. Discourse, image, and computer.- 1.2. Visual perception.- 1.2.1. Thought and vision.- 1.2.2. The mechanisms of photoreception.- 1.2.3. The optical paths.- 1.2.4. The treatment of visual information.- 1.2.5. Multiplexing of sensorial messages.- 1.3. Different aspects of images.- 1.3.1. Attempt to define the concept of an image.- 1.3.2. Physical images.- 1.3.3. Psychic images.- 1.3.4. The particular status of numerical images.- 2. Numerical images.- 2.1. Image and computer.- 2.1.1. Images as memory.- 2.1.1.1. Psychic images and memory.- 2.1.1.2. Encoding and decoding of images.- 2.1.2. Representations.- 2.1.2.1. Analogue representation.- 2.1.2.2. Numerical representation.- 2.1.3. Numerical (digital) images.- 2.1.3.1. Screen memory.- 2.1.3.2. Vector memory.- 2.2. The graphical peripherals.- 2.2.1. Central unit and peripherals.- 2.2.2. Graphical output peripherals.- 2.2.2.1. History.- 2.2.2.2. Printers, tape and card punchers.- 2.2.2.3. Plotters.- 2.2.2.4. Cathode ray tubes.- 2.2.2.5. COMs.- 2.2.2.6. Flat screens.- 2.2.2.7. Laser techniques.- 2.2.3. Peripherals of graphics processing.- 2.2.3.1. The optical pen.- 2.2.3.2. Data tablet.- 2.2.3.3. Mouse.- 2.2.3.4. Digitizers of images.- 2.2.3.5. Others.- 2.2.4. Interaction.- 2.3. Cathode ray tubes.- 2.3.1. History.- 2.3.2. Principles of functioning.- 2.3.3. Scanning modes.- 2.3.4. Graphics processor.- 2.3.5. Tubes with free scanning.- 2.3.6. Tubes with memory (or with image preservation).- 2.3.7. Tubes with recurrent scanning.- 2.3.8. Color screens.- 2.3.9. Linearization of the intensity levels.- 2.3.10. Look up tables.- 2.3.10.1. Principle.- 2.3.10.2. Applications.- 2.3.10.3. Digitizers of images.- 2.4. Flat screens.- 2.5. The programming of graphics processors.- 3. Modelling problems.- 3.1. Image and formalism.- 3.1.1. Image and model.- 3.1.2. The computer as a tool of creation.- 3.1.3. The different levels of description.- 3.2. The modelling of images.- 3.2.1. Processing of a numerical image.- 3.2.2. Synthesis.- 3.2.3. Abstract plane images.- 3.2.4. Figurative plane images.- 3.2.5. Three-dimensional images.- 3.2.6. Realistic images.- 3.3. Constructive geometry.- 3.3.1. Modular structures.- 3.3.2. Euler operators.- 3.3.3. Applications.- 3.4. Polyhedral models.- 3.4.1. Polyhedral approximation of a curved surface.- 3.4.1.1. Modelling by means of facets.- 3.4.1.2. Triangulation methods.- 3.4.2. Data structures associated with polyhedral descriptions.- 3.4.3. Domains of applications.- 3.5. Curves and surfaces.- 3.5.1. Graphical primitives.- 3.5.2. Generating plane curves.- 3.5.2.1. Polygonal approximations.- 3.5.2.2. Reduction of numerical plane curves.- 3.5.3. Parametic curves and surfaces.- 3.5.3.1. Cubics.- 3.5.3.2. Coons’ surfaces.- 3.5.3.3. Bezier curves and surfaces.- 3.5.3.4. B-spline curves and surfaces.- 3.5.3.5. Beta-splines.- 3.5.4. The visualization of curves and surfaces.- 3.6. Fractal objects.- 3.6.1. Fractal objects according to Benoit Mandelbrot.- 3.6.1.1. Continuity and reality.- 3.6.1.2. The concept of dimension.- 3.6.1.3. Measure.- 3.6.1.4. The concept of an internal homothety.- 3.6.1.5. Homothety dimension.- 3.6.1.6. Stochastic models.- 3.6.1.7. Terrain models.- 3.6.2. Algorithms for the generation of three-dimensional fractal objects.- 3.6.2.1. Numerical images and fractal dimension.- 3.6.2.2. Iteration of functions.- 3.6.2.3. Stochastic models.- 3.6.2.4. Stochastic primitives.- 3.6.2.5. Stochastic movement.- 3.7. Systems of particles.- 3.7.1. The modeling of unsharp objects.- 3.7.2. Systems of particles.- 3.7.3. Application to the modelling of fire and explosions.- 3.8. Modelling waves.- 3.8.1. Explanation of the problem.- 3.8.2. Peachey’s model.- 3.8.3. The model of Fournier and Reeves.- 3.9. The synthesis of fabrics.- 3.9.1. Explanation of the problem.- 3.9.2. Weil’s model.- 3.9.2.1. The conditions.- 3.9.2.2. Approximation of the surface.- 3.9.2.3. Iterative approximation.- 3.10. The modelling of shells and plants.- 3.10.1. Explanation of the problem.- 3.10.2. Kawaguchi and the sea.- 3.10.3. Plants and formal languages.- 3.10.4. Tree-like models of plants.- 3.10.5. AMAP.- 4. Problems of visualization.- 4.1. The visualization of numerical images.- 4.1.1. Numerical images.- 4.1.2. Coding numerical images.- 4.1.2.1. Run-length coding.- 4.1.2.2. Coding according to Freeman.- 4.1.2.3. Coding by means of quaternary trees.- 4.2. 2D-images.- 4.2.1. Graphical primitives.- 4.2.1.1. Points.- 4.2.1.2. Segments.- 4.2.1.3. Simple figures.- 4.2.2. 2D clipping.- 4.2.2.1. Explanation of the problem.- 4.2.2.2. Clipping of a segment by a rectangular window.- 4.2.2.3. Clipping by an arbitrary window.- 4.2.2.4. The clipping of polygons.- 4.2.2.5. Concave windows.- 4.2.3. Colouring surfaces.- 4.2.3.1. Explanation of the problem.- 4.2.3.2. Algorithms which work on the image memory.- 4.2.3.3. Algorithms which use associated data structures.- 4.2.4. The use of smoothing.- 4.2.4.1. Principles.- 4.2.4.2. Smoothings defined on the basis of poles.- 4.2.4.3. Methods of colour points.- 4.3. Perspective projections.- 4.3.1. 3D-Images.- 4.3.1.1. Object space and image space.- 4.3.1.2. The perception of space.- 4.3.1.3. Perspective projection.- 4.3.1.4. The problem of entering the data.- 4.3.2. Homogeneous coordinates.- 4.3.3. The matrix associated to a linear transformation.- 4.3.3.1. Matrix of a linear transformation.- 4.3.3.2. Product of linear transformations.- 4.3.3.3. Examples.- 4.3.4. Perspective transformations.- 4.3.5. Clipping.- 4.3.6. Coordinate system of the screen and perspective projection.- 4.4. Aliasing.- 4.4.1. Explanation of the problem.- 4.4.2. Filtering a numerical image.- 4.4.3. Increasing the resolution.- 4.4.4. Random sampling.- 4.4.5. The method of dividing pixels.- 4.5. Motifs, mappings.- 4.5.1. Explanation of the problem.- 4.5.2. Motifs.- 4.5.3. Maps.- 4.6. Textures.- 4.6.1. Definition of the concept of texture.- 4.6.2. Analysis and synthesis of textures.- 4.6.3. Blinn’s method.- 4.6.4. 3D-textures.- 5. The elimination of hidden parts.- 5.1. The problem of hidden parts.- 5.1.1. Explanation of the problem.- 5.1.2. Principles.- 5.2. Elements of geometry.- 5.2.1. Box tests.- 5.2.2. Belonging to the interior of a polygon.- 5.2.3. Equations of planes.- 5.2.4. Sorting problems.- 5.2.5. Coherence.- 5.3. Classification of algorithms.- 5.4. The algorithm with a mobile horizon.- 5.4.1. Principles.- 5.4.2. The algorithm.- 5.4.3. Implementation.- 5.5. Roberts’ algorithm.- 5.5.1. Principles.- 5.5.2. Elimination of back facets.- 5.5.3. Elimination of the remaining edges.- 5.6. Schumacker’s algorithm.- 5.7. The algorithm of Newell-Newell-Sancha.- 5.7.1. Principles.- 5.7.2. Newell’s algorithm.- 5.8. Warnock’s algorithm.- 5.8.1. Principles.- 5.8.2. Optimization.- 5.9. Scan-line algorithms.- 5.10. Application of automatic programming: Goad’salgorithm.- 5.11. Using coherence.- 5.12. The z-buffer algorithm.- 5.12.1. Principles.- 5.12.2. Implementation.- 5.12.3. Limitations of the method.- 5.12.4. Scan-line and z-buffer.- 5.13. The ray-tracing algorithm.- 5.13.1. Principles.- 5.13.2. Implementation.- 5.13.3. Calculating intersections.- 5.13.4. Arranging the objects in a hierarchy.- 6. Illumination models.- 6.1. Illumination of a scene.- 6.2. The models of Phong and of Blinn.- 6.2.1. Diffuse illumination (or ambient lighting).- 6.2.2. Lambert’s law.- 6.2.3. Specular reflection.- 6.2.4. Multiple sources.- 6.3. Cook’s model.- 6.3.1. The model.- 6.3.2. Bidirectional distribution of reflected light.- 6.3.3. Spectral distribution of reflected light.- 6.4. Transparency.- 6.5. Smoothing methods.- 6.5.1. The smoothing problem.- 6.5.2. Gouraud smoothing.- 6.5.3. Phong smoothing.- 6.5.4. Comparison of the two methods.- 6.6. Shadows.- 6.6.1. Explanation of the problem.- 6.6.2. Projection method.- 6.6.3. z-buffer method.- 6.6.4. Ray-tracing method.- 6.7. Radiosity.- 6.7.1. The illumination problem.- 6.7.2. The radiosity principle.- 6.7.3. Calculation of the form coefficients.- 6.7.4. Cohen’s hemi-cube.- 6.8. Ray-tracing.- 6.8.1. Principles.- 6.8.2. Whitted’s model.- 6.8.3. Calculating secondary rays.- 6.8.4. Anti-aliasing.- 6.8.5. Optimization.- 6.8.5.1. Box tests.- 6.8.5.2. Optimization according to the type of primitives.- 6.8.6. Bundle tracing.- 6.8.6.1. Ray and bundle.- 6.8.6.2. Representation of a ray in a bundle.- 6.8.6.3. Matrices associated to optical systems.- 6.8.6.4. Evaluation of the deviation.- 6.9. Simulation of clouds and fluffy surfaces.- 6.9.1. Dispersion models in a cloud.- 6.9.2. Phase functions.- 6.10. Simulation of atmospheric dispersion.- 6.10.1. Explanation of the problem.- 6.10.2. Nishita’s model.