Preprocessing device, determination system, preprocessing method, and preprocessing program
A preprocessing device includes processing circuitry configured to acquire coordinate information of respective vertexes of a polygon for inside/outside determination and reduce the vertexes of the polygon for inside/outside determination as preprocessing of determination processing of determining whether a coordinate to be determined exists inside or outside the polygon for inside/outside determination, and output the coordinate information of the respective vertexes of the polygon after the vertexes are reduced, to a device which performs the determination processing.
1. A preprocessing device comprising:
processing circuitry configured to:
acquire coordinate information of respective vertexes of a polygon for inside/outside determination, the polygon having an elongated shape;
prior to the inside/outside determination, reduce the vertexes of the polygon for inside/outside determination while maintaining the elongated shape of the polygon as preprocessing of determination processing of determining whether a coordinate to be determined exists inside or outside the polygon for inside/outside determination; and
output the coordinate information of the respective vertexes of the polygon after the vertexes are reduced, to a device which performs the determination processing.
2. The processing device according to claim 1 , wherein, to reduce the vertexes of the polygon, the processing circuitry is further configured to:
(i) select two vertexes of the polygon as a start point and an end point, respectively,
(ii) plot a line between the start point and the end point,
(iii) determine a vertex between the start point and the end point that is furthest from the line,
(iv) set the vertex that is further from the line as a new end point, and
(v) repeat (i)-(iv) until there are no vertexes between the start point and the end point that are at least a predetermined distance from the line.
3. The processing device according to claim 1 , wherein the processing circuitry uses a Ramer-Douglas-Peucker algorithm to reduce the vertexes of the polygon.
4. The processing device according to claim 1 , wherein the coordinate information includes vertex coordinate pairs for each vertex of the polygon.
5. The processing device according to claim 1 , wherein the inside/outside determination is performed using one of a Crossing Number method or a Winding Number method.
6. A determination system comprising:
a determination device including processing circuitry configured to perform determination processing of determining whether a coordinate to be determined exists inside or outside a polygon for inside/outside determination, the polygon having an elongated shape; and
a first preprocessing device including first processing circuitry configured to perform preprocessing of the determination processing,
the first processing circuitry being configured to:
acquire coordinate information of respective vertexes of the polygon for inside/outside determination and, prior to the inside/outside determination, reduce the vertexes of the polygon for inside/outside determination while maintaining the elongated shape of the polygon as preprocessing, and
output reduced polygon information which is the coordinate information of the respective vertexes of the polygon after the vertexes are reduced,
the processing circuitry being configured to determine whether the coordinate to be determined exists inside or outside the polygon for inside/outside determination using information after the preprocessing.
7. The determination system according to claim 6 , further including:
a second preprocessing device including second processing circuitry configured to perform preprocessing of the determination processing,
the second processing circuitry being configured to:
acquire the coordinate information of the respective vertexes of the polygon for inside/outside determination and divide the polygon for inside/outside determination into a plurality of polygons as preprocessing, and
output the coordinate information of the respective vertexes of the respective divided polygons for inside/outside determination as the divided polygon information as preprocessing.
8. The determination system according to claim 6 , further including:
a third preprocessing device including third processing circuitry configured to perform preprocessing of the determination processing,
the third processing circuitry being configured to:
acquire coordinate information of the coordinate to be determined and the coordinate information of the respective vertexes of the polygon for inside/outside determination and rotate the coordinate to be determined and the polygon for inside/outside determination, and
output the coordinate information of the respective vertexes of the rotated polygon for inside/outside determination and the rotated coordinate to be determined as rotated coordinate information.
9. The determination system according to claim 6 , wherein, to reduce the vertexes of the polygon, the first processing circuitry is further configured to:
(i) select two vertexes of the polygon as a start point and an end point, respectively,
(ii) plot a line between the start point and the end point,
(iii) determine a vertex between the start point and the end point that is furthest from the line,
(iv) set the vertex that is further from the line as a new end point, and
(v) repeat (i)-(iv) until there are no vertexes between the start point and the end point that are at least a predetermined distance from the line.
10. The determination system according to claim 6 , wherein the first processing circuitry uses a Ramer-Douglas-Peucker algorithm to reduce the vertexes of the polygon.
11. The determination system according to claim 6 , wherein the coordinate information includes vertex coordinate pairs for each vertex of the polygon.
12. The determination system according to claim 6 , wherein the inside/outside determination is performed using one of a Crossing Number method or a Winding Number method.
13. A preprocessing method comprising:
acquiring coordinate information of respective vertexes of a polygon for inside/outside determination the polygon having an elongated shape;
prior to the inside/outside determination, reducing the vertexes of the polygon for inside/outside determination while maintaining the elongated shape of the polygon as preprocessing of determination processing of determining whether a coordinate to be determined exists inside or outside the polygon for inside/outside determination, by processing circuitry; and
outputting the coordinate information of the respective vertexes of the polygon after the vertexes are reduced, to a device which performs the determination processing.
14. A non-transitory computer-readable medium encoded with computer-readable instructions that, when executed by processing circuitry, cause the processing circuitry to perform the method of claim 13 .
15. The preprocessing method according to claim 13 , further comprising:
(i) selecting two vertexes of the polygon as a start point and an end point, respectively;
(ii) plotting a line between the start point and the end point;
(iii) determining a vertex between the start point and the end point that is furthest from the line;
(iv) setting the vertex that is further from the line as a new end point; and
(v) repeating (i)-(iv) until there are no vertexes between the start point and the end point that are at least a predetermined distance from the line.
16. The preprocessing method according to claim 13 , wherein the first processing circuitry uses a Ramer-Douglas-Peucker algorithm to reduce the vertexes of the polygon.
17. The preprocessing method according to claim 13 , wherein the coordinate information includes vertex coordinate pairs for each vertex of the polygon.
18. The preprocessing method according to claim 13 , wherein the inside/outside determination is performed using one of a Crossing Number method or a Winding Number method.