User-Defined Clipping in Object Space for 3D Graphics

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Current 3D graphics processing in hand-held devices faces performance issues due to the need for extensive computations to transform vertices from object space to eye space for user-defined clipping, which consumes significant power and reduces performance.

Innovation Solution

Implementing user-defined clipping in object space, where vertex coordinates are clipped using clip planes directly in object space, reducing the need for transformation into eye space and allowing for combined modelview and projection transformations into a single matrix, thereby reducing computational load.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Measurement precision

If user-defined clipping is performed in eye space by transforming vertices from object space to eye space, then clipping accuracy is improved, but computational load and power consumption increase significantly

Engineering Contradiction:

Improveclipping accuracyVSAvoidpower consumption

Core Design Contradiction:

Measurement precisionVSUse of energy by moving object

Solution Approach 1:

Instead of transforming vertices from object space to eye space for clipping, the patent inverts the approach by transforming clip planes from eye space to object space and performing clipping directly in object space. This eliminates the need for vertex transformation while maintaining clipping functionality, thereby reducing computational load and power consumption.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the coordinate space parameter from eye space to object space for performing clipping operations. By transforming the clip plane parameters (normal vector and distance) from eye space to object space using the inverse modelview matrix, the clipping operation can be performed in object space without transforming vertices, thus reducing the number of computations required.

Inventive Principle:

Principle #35Parameter changes

2Ease of operation

If vertices are transformed from object space to eye space for user-defined clipping, then clipping functionality is achieved, but processing time increases

Engineering Contradiction:

Improveclipping functionalityVSAvoidprocessing time

Core Design Contradiction:

Ease of operationVSLoss of time

Solution Approach 1:

The patent inverts the conventional clipping approach by transforming clip planes to object space rather than transforming vertices to eye space. This allows clipping to be performed in object space using the original vertex coordinates, eliminating the time-consuming vertex transformation step while preserving clipping functionality.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent performs preliminary transformation of clip planes from eye space to object space before clipping operations. By pre-computing the transformed clip plane parameters and storing them in object space coordinates, the actual clipping operations can proceed without additional transformation computations, reducing processing time.

Inventive Principle:

Principle #10Preliminary action

3Measurement precision

If multiple clip planes are defined in eye space and vertices are transformed to eye space for clipping, then accurate clipping is achieved, but the number of computations increases

Engineering Contradiction:

Improveclipping precisionVSAvoidcomputational complexity

Core Design Contradiction:

Measurement precisionVSDevice complexity

Solution Approach 1:

The patent applies the inversion principle by transforming multiple clip planes from eye space to object space and performing all clipping operations in object space. This eliminates the need to transform vertices to eye space multiple times for each clip plane test, significantly reducing computational complexity while maintaining clipping precision.

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The patent changes the working coordinate space from eye space to object space for clipping operations. By transforming the clip plane parameters (a, b, c, d) from eye space to object space using the inverse modelview matrix, all subsequent clipping tests can be performed using original object space vertex coordinates, reducing the overall computational complexity.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS9024969B2Method and device for performing user-defined clipping in object space

Publication Date: 2015.05.05 QUALCOMM INC

AI summary

A method and device for performing and processing user-defined clipping in object space to reduce the number of computations needed for the clipping operation. The method and device also combine the modelview transformation of the vertex coordinates with projection transform. The user-defined clipping in object space provides a higher performance and less power consumption by avoiding generation of eye coordinates if there is no lighting. The device includes a driver for the user-defined clipping in the object space to perform dual mode user-defined clipping in object space when a lighting function is disabled and in eye space when the lighting function is enabled.