Computer animation can be viewed from different angles and divided into sections. The animation techniques also differ due to the different computer graphics formats. In the 2D-technique graphics are mostly created in pixelmaps. The 3D-technique works only with vector graphics.
In the following chapters Pixmap animation and morphing in 2D are described. Subsequently, the modelling of 3D worlds and computer-aided animation are presented.
The application areas of computer animation are games, presentations and simulations.
The terms animation and simulation are often not clearly separated. Simulation is generally a simulation of object behavior under certain physical laws. The animation shows the perceptible changes of the objects in a certain period of time. However, simulations can take place completely without visualization and offer only a final result, so they do not belong to the animation.
Pixmaps are created with a paint program. It is also possible to scan an original and process it in the computer. Painting programs offer functions for creating and manipulating images. Different elements like circles, rectangles, etc. can be inserted into the picture. Image sections can, for example, be enlarged, deleted or discolored. Special programs for editing photos also offer functions such as contrast and brightness changes or color filters.
The 2D graphics technology of the computer resembles the cartoon in many areas. The separation of moving figures and (several) backgrounds is just as possible as in analog foil technology. This technique is used, for example, in games. Animated Pixmaps(Sprites) are moved over a rigid background. Procedures that computer animation programs offer to facilitate the creation of a movie and films.
An example for the simple creation of an animation with the help of a computer is morphing. Morphing changes the shape and color of an image at the same time. The goal is to create a smooth transition between two pixmaps. The user has to determine prominent points in the initial and final image. For example, in portrait photos, eyes, corners of the mouth, nose, etc. are marked. The points are connected by a net, which integrates the pixelmaps into image areas.
Creation of a Morphing
In order to change the shape of the face, the points are moved from the initial position to the final position. However, this also changes the net. The computer scales the image areas to the new shape, as shown in Animation studio in Singapore. The pixels of the intermediate images are mixed from the colors of the initial and final image. The percentage of the final image increases.
When generating computer graphics, a distinction can be made between direct and indirect mode. Graphics systems that generate images in direct mode (e.g. painting programs) can insert predefined shapes such as rectangles, circles or polygons into the Pixmap, but the user cannot select and change an already drawn shape. The program inserts the shapes directly into the graphic without saving the shapes separately. Manipulations can be done on pixel level. A set of pixels, often a rectangular image section, can be selected and, for example, changed in color and size.
Drawing programs work in indirect mode
In contrast to the drawing program, the user can select and edit the previously placed shapes at any time. Depending on the application, the predefined shapes are also called symbols, templates or objects. The objects are saved by the graphics system with the associated attributes, such as size and position.
This enables the objects to be edited later. The graphic objects are usually composed of polylines and stored in the graphics system as vectors which represent the individual lines. If an object is changed by the user, the drawing program automatically generates an updated graphic.
The use of vector graphics has advantages in animation
Since the attributes of a graphic object are saved with the vector graphic, all attributes can also be animated. The user is no longer limited to the animation of pixel position and color, but can also animate objects in size, position, color and shape. When creating simulations, properties such as weight, temperature, etc. can be assigned to the objects in addition to the geometric attributes listed above. Complex processes are simulated by changing these properties over time and can be displayed as animations.
The shader defines surface structures for objects with optical properties such as transparency and reflection behavior. The individual objects are combined to form a scene. Light sources and camera are also positioned.
The renderer calculates (renders) a graphic from the data of the modeler and shader. Depending on the rendering method used, the shadow cast of the objects and the reflection and transparency of the surfaces are taken into account. In the animation module the user can define movements and state changes of the objects, the camera and the lights.