A Realization Method of Pointer-type Virtual Dashboard

Abstract

The invention discloses a realization method of a pointer type virtual instrument panel. The realization method comprises the following steps: an equipment context is built; a dial background is loaded; a memory context is duplicated, and the dial background serves as a canvas; a pointer picture is loaded; the size of the pointer picture is obtained; a pointer rotating center is set; after a pointer rotates an angle alpha, the rasterization treatment is performed with a coordinate as a rotating center according to step distance; each small rectangle coordinate is obtained; the pointer rotating the angle alpha is drawn in one of the memory contexts; the picture in the corresponding position of the memory context is duplicated in the equipment context for displaying; after the angle alpha is changed, the pointer is drawn in the memory context again; the last pointer display content in the equipment context is erased by the corresponding background picture in the other one of the memory contexts according to the pre-change rectangle coordinate of the angle alpha; and the picture in the corresponding position of the memory context is duplicated in the equipment context for displaying according to the post-change rectangle coordinate of the angle alpha.

Description

technical field [0001] The invention belongs to the technical field of motor vehicle dashboards, and in particular relates to a method for realizing a pointer-type virtual dashboard. Background technique [0002] At present, most of the most common instrument panels use moving coil or moving magnet analog instruments, and stepping motor digital instruments to display information. With the further development of computers and liquid crystal display technologies, some equipment gradually adopts LCD screens for human information display. As a result, the instrument panel has become more and more beautiful, with more and more functions, starting from practicality and becoming fashionable and dazzling, and finally completing the perfect combination of practicality and fashion. [0003] In order not to change the usage habits of operators, although the dashboards of many devices are gradually upgraded to LCD screens, parameters such as engine speed and vehicle speed must be displa...

AI Technical Summary

Problems solved by technology

[0004] First of all, when the hands of the watch rotate, it is necessary to simulate the inertia links such as acceleration and deceleration of the analog instrument, and the display must be continuous and cannot jump step by step;

[0005] Secondly, the refresh rate should be high, generally reaching the millisecond level. Due to the fast refresh rate, it is easy to cause the screen to flicker when the background is redrawn.

[0006] In view of the above problems, many manufacturers use double buffering technology to eliminate the flickering problem of the instrument display screen, but the effect is not ideal. The double buffering method only solves the efficiency of background graphics drawing and complex graphics calculation, but it cannot improve the efficiency of reading from the cache. As the screen and resolution gradually increase, the number of virtual instruments displayed increases, and the problem of flickering becomes very obvious.

Due to the limited resources of embedded devices, some manufacturers sacrifice hardware costs to solve software problems, resulting in increased costs

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