Navigation system with anti-alias map display

• US 6,163,269 A
• Filed: 09/24/1998
• Issued: 12/19/2000
• Est. Priority Date: 05/05/1998
• Status: Expired due to Term

• Current Assignee: Beacon Navigation GmbH (Beacon Navigation Incorporated)
• Original Assignee: Magellan DIS, Inc.
• Inventors: Millington, Jeffrey Alan, Slominski, Anthony Albert
• Primary Examiner(s): Hofsass, Jeffery A.
• Assistant Examiner(s): TWEEL JR, JOHN ALEXANDER
• Application Number:
  US09/160,068
• Time in Patent Office: 817 Days
• Field of Search: 340/815.4, 345/136, 345/147
• US Class Current: 340/815.4
• CPC Class Codes: G01C 21/367 Details, e.g. road map scale, orientation, zooming, illumination, level of detail, scrolling of road map or positioning of current position marker
• CPC Class Codes: G06T 11/203 Drawing of straight lines or curves
• CPC Class Codes: G09G 5/026 Control of mixing and/or overlay of colours in general G09G5/022 and G09G5/024 take precedence

Abstract

A navigation system includes a display displaying a map of roads from a road database. The navigation system utilizes a palette of colors to display the road and background on the display. The palette preferably includes a plurality of shades for each of a plurality of colors to be displayed including the background color and the road color. The roads on the display are preferably anti-aliased by indexing a different intensity of the shade of the object based upon the relative position of the pixel and an ideal object area.

Claims

1. A method for displaying a map in a navigation system including the steps of:

a. providing a palette having a plurality of shades of each of a plurality of colors;

b. displaying each of a plurality of pixels at one of the plurality of colors;

c. displaying the map including a plurality of road lines; and

d. anti-aliasing the road lines utilizing the plurality of colors.

2. The method of claim 1 further including the steps of:

e. utilizing the plurality of shades in the palette to anti-alias the road lines; and

f. displaying the road lines as a first color of the plurality of colors against a background of a second color of the plurality of colors.

3. The method of claim 2 further including the steps of:

g. comparing each of the pixels to an ideal road line; and

h. varying an intensity of the color of the pixels based upon said step g.

4. The method of claim 3 wherein said intensity of the color is varied in said step h by selecting one of the shades of the first color and displaying different pixels in the road lines as different shades of the first color.

5. The method of claim 4 further including the step of reducing the intensity of the first color of the pixel proportionally to a portion of the pixel not lying within the ideal road line.

6. The method of claim 5 further including the steps of:

displaying at least one of the pixels at the background color based upon a threshold portion of one of said pixels not being within the ideal road line.

7. A display system for a navigation system comprising:

a palette of a plurality of intensities of each of a plurality of colors;

an array of pixels, each selectively illuminated at one of said intensities of said colors;

said pixels selectively illuminated to display a road line of a first color of said plurality of colors against a background of a second color of said plurality of colors, said pixels comprising said road line being displayed at different intensities of said first color from said palette.

8. The display system of claim 7 wherein pixels comprising said road line are compared to an ideal road line, said intensities of said pixels being varied based upon said comparison.

9. The display system of claim 8 wherein said pixels comprising said road line are displayed at varying intensities from said palette proportionally to the overlap of said pixels with said ideal road line.

10. The display system of claim 9 wherein pixels having overlap of said ideal line less than a predetermined threshold greater than zero are displayed at the color of the background.

11. A display system for a navigation system comprising:

a palette of a plurality of intensities of each of a plurality of colors;

an array of pixels, each selectively illuminated at one of said intensities of said colors;

said pixels selectively illuminated to display a road line of a road color of said plurality of colors against a background color of said plurality of colors, said pixels comprising said road line being compared to an ideal road line, said pixels displayed at varying intensities of said road color from said palette based upon said comparison proportionally to the overlap of said pixels with said ideal road line and pixels having overlap of said ideal line less than a predetermined threshold greater than zero are displayed at the color of the background.