Drawing device of move-target image and display system for vehicle

1. A drawing device for continuously drawing a move-target image as a moving picture on a display image displayed on a display unit, the drawing device comprising:

a drawing position identification unit which is configured to identify a current drawing position at which the move-target image is drawn on the display screen;

a past drawing position storage unit in which is stored a plurality of past drawing positions where the move-target image is drawn previously;

an afterimage-reducing region detection unit which is configured to detect an afterimage-reducing region of the move-target image;

an afterimage-reducing image drawing unit which is configured to draw an afterimage-reducing image in the afterimage reducing region;

a move-target image drawing unit which is configured to draw the move-target image at the current drawing position; and

an afterimage-reducing region dividing unit which is configured to divide the afterimage-reducing region into a plurality of afterimage-reducing divided regions, wherein

the afterimage-reducing image drawing unit draws each of divided afterimage-reducing images to be drawn in the plurality of afterimage-reducing divided regions so that its gradation is reduced step-by-step as it gets away from the move-target image, and wherein

the afterimage-reducing region dividing unit selects a first past drawing position from the plurality of past drawing positions, the afterimage-reducing region extending from the current drawing position to the selected first past drawing position, and

the afterimage-reducing region dividing unit selects one or more second past drawing positions from the plurality of past drawing positions, the one or more second past drawing positions existing between the first past drawing position and the current drawing position, wherein the plurality of afterimage-reducing divided regions are based on the current drawing position, the first past drawing position and the one or more second past drawing positions.

2. The drawing device according to claim 1 , comprising:

a previous move-target image erasing unit which is configured to erase a previous move-target image in accordance with an identification of the current drawing position performed by the drawing position identification unit.

3. The drawing device according to claim 1 , wherein

the move-target image is an image which indicates a display of rotating a pointer, and

the afterimage-reducing image drawing unit draws each of divided afterimage-reducing images to be drawn in the plurality of afterimage-reducing divided regions so that its gradation is reduced gradually as it comes close to a rotational center of the pointer.

4. A display system for a vehicle comprising the drawing device according to claim 1 .

5. The drawing device according to claim 1 , wherein

the plurality of afterimage-reducing divided regions are generated based on coordinates of the current drawing position and the plurality of stored past drawing positions.

6. The drawing device according to claim 1 , wherein

the plurality of afterimage-reducing divided regions are generated by dividing the afterimage-reducing region with a center line connecting a root and a head of each of the plurality of stored past drawing positions.

7. The drawing device according to claim 1 , wherein

the plurality of afterimage-reducing divided regions at least includes a first divided region between the current drawing position and the one or more second past drawing positions, and a second divided region between the first past drawing position and the one or more second past drawing positions.