Abstract: A value is assigned to a layout bound of a first node in a scene graph. The layout bound constitutes a bounding volume for the object corresponding to the node and may be the display properties of the object and a first set of display modifiers for the node but not a second set. A display layout is calculated for a second node in the scene graph based on the value of the layout bound. Then, nodes of the scene graph are rendered to generate a display on a display device according to the calculated display layout. The value of the layout bound may be assignable, creating greater flexibility in controlling layout. Additionally, the value assigned to the layout bound may be changed. In this way, layout of nodes with respect to each other is flexible and visual effects and animations can either be factored into that layout or not.

Abstract: A value is assigned to a layout bound of a first node in a scene graph. The layout bound constitutes a bounding volume for the object corresponding to the node and may be the display properties of the object and a first set of display modifiers for the node but not a second set. A display layout is calculated for a second node in the scene graph based on the value of the layout bound. Then, nodes of the scene graph are rendered to generate a display on a display device according to the calculated display layout. The value of the layout bound may be assignable, creating greater flexibility in controlling layout. Additionally, the value assigned to the layout bound may be changed. In this way, layout of nodes with respect to each other is flexible and visual effects and animations can either be factored into that layout or not.

Abstract: A system and method for communicating 3D branch graph data and updates to branch graph data between clients and a display server in a 3D window system. A client locally creates a branch graph. When the client ready to make the branch graph live remote, it sends the branch graph to the display server using at least one batch protocol request. The display server builds a copy of the branch graph and attaches it to a centralized scene graph that it manages. The client may subsequently induce detachment of the branch graph from the scene graph. The client may buffer up changes to the local branch graph when its remote counterpart (in the display server) is not attached to the scene graph. The buffered changes may be sent to the display server using at least one batch protocol request when the client is again ready to make the branch graph live remote.

Abstract: A graphics system including a frame buffer and a processing unit. The frame buffer contains N slots per pixel. Slots are used to store fragments. Suppose the N slots for a given pixel are occupied. In response to having received (or generated) a new fragment for the pixel, the processing unit may (a) blend the two backmost slots to liberate space for the new fragment, (b) blend the new fragment with the backmost slot in a first order, or, (c) blend the new fragment and the backmost slot in a second order. The choice of (a), (b) or (c) depends on the relationship of the new fragment's z value to the z values of the two backmost slots. The processing unit may be programmably configured to perform multi-pass order independent transparency in either front-to-back order or back-to-front order.

Abstract: A method and apparatus for operating a computer graphics system to perform a conditional test on a node in a graphics data structure during the traversal of the graphics data structure by a structure walker. The graphics system is operated to manipulate data contained in a memory to define a value for an operand that is to be tested. The system accesses the operand from the memory. A structure walker performs a test on the value of the operand during traversal of the graphics data structure. Depending upon the result of the test, the structure walker traverses one of several paths in the graphics data structure to create a graphics display.

Abstract: A method for operating a computer graphics system to build custom nodes containing commands and data information that is stored in a data structure in the graphics subsystem. A host processor calls routines which build the custome nodes. A structure walker traverses the data structure and extracts the information from the data structure to pass it to the graphics subsystem for display. The use of custom nodes increases the flexibility of advanced graphics data structures bny allowing the creation of other data structures during execution of a first data structure.

Abstract: A host system executes one or more application programs which results in graphic data structures. These graphic data structures are then continuously and asynchronously traversed. Traversal requests by competing application programs are scheduled and performed so that each application views the graphics processing as its own. The traversal and ordering of traversal requests provide efficient use of resources for multiple application programs.

Abstract: A line-filtering antialiasing apparatus for a computer graphics display, with a set of parallel pixel processors functioning independently in a line drawing system and with plotting apparatus assigning individual pixels to the processors so as to track to the line. An optimum number of sixteen processors filter proximity data based on the vertical distance from a pixel center to the line center for shading pixels to gray-scale intensity in an area of influence four pixels wide. Line terminations are extended and shaded at the termination area. Pixel values for individual lines are summed to develop a total display image.