CN110533779B - Reconstruction method for overlapping part of ocean structure and water surface grid - Google Patents
Reconstruction method for overlapping part of ocean structure and water surface grid Download PDFInfo
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Abstract
The invention relates to the technical field of graphic data processing, in particular to a reconstruction method for an overlapping part of an ocean structure and a water surface grid, which comprises the following steps: a grid marking step, marking the water surface grid intersected with the sea structure grid as an intersected grid; a grid refining step, namely refining the intersected grids, and repeating the grid marking step and the grid refining step until the grid precision reaches the standard; a step of grid deletion, which is to take the central point of the water surface grid as an end point to make a vertical upward ray, obtain the number of intersection points of the ray and the ocean structure grid, mark the water surface grid as an external grid when the number of the intersection points is an even number, and mark the water surface grid as an internal grid when the number of the intersection points is an odd number; and marking the water surface grids except the intersected grids in sequence, and deleting the intersected grids and the internal grids from the water surface grids after marking is finished. By adopting the scheme, the water surface grids of the overlapped part can be quickly reconstructed, so that high-quality water surface grids can be efficiently obtained.
Description
Technical Field
The invention relates to the technical field of graphic data processing, in particular to a reconstruction method for an overlapping part of an ocean structure and a water surface grid.
Background
In the process of solving the hydrodynamic problem by applying a CFD (Computational Fluid Dynamics) method, grids are usually generated on the water surface and the ocean structure respectively, so that the grids of the ocean structure and the water surface are overlapped, the phenomenon is not in accordance with the actual physical significance, certain influence is caused on calculation, and the display effect is influenced when a post-processing result is displayed.
The method comprises the steps of giving a grid of an ocean structure and a water surface, generating a computational grid which is the same as an actual physical state through identification, judgment, refinement and grid reconstruction, and having certain significance in solving a computational problem of the CFD hydrodynamics. Because the water surface usually adopts a more regular calculation domain, the grid generation is simpler and the quality is higher, and the method of separately generating the grid has more practical value. However, how to remove the overlapped part of the separately generated grids when combining is one of the more urgent problems to be solved in the current CFD hydrodynamics calculation problem.
To solve this problem, engineering usually makes geometrically related boolean operations on a water surface geometric model and an ocean structure model. The generated new geometric model has a complex structure, and part of geometric features are obvious, so that a high-quality grid cannot be generated. The grid quality at the overlapping part of the water surface and the ocean structure can not meet the calculation requirement, and the grid quality of other parts can be influenced. Therefore, a great amount of manual operations need to be added to modify the mesh topology structure so as to improve the mesh quality and greatly lengthen the calculation period, so that a reconstruction method for an overlapped mesh capable of efficiently generating a high-quality water surface mesh when an ocean structure and the water surface mesh are combined is urgently needed.
Disclosure of Invention
The invention aims to provide a reconstruction method for an overlapping part of an ocean structure and a water surface grid, which can rapidly reconstruct the water surface grid of the overlapping part and efficiently acquire the high-quality water surface grid.
The basic scheme provided by the invention is as follows: a reconstruction method for overlapping portions of a marine structure and a water surface mesh, comprising the steps of:
a grid marking step, namely sequentially judging whether the water surface grid is intersected with the ocean structure grid or not, and if so, marking the water surface grid as an intersected grid;
a grid refining step, namely refining the intersected grids, judging whether the grid precision of the refined intersected grids reaches the standard or not, and repeating the grid marking step and the grid refining step if the grid precision of the refined intersected grids does not reach the standard;
a grid deleting step, namely, when the grid precision of the thinned intersected grids reaches a standard, taking any point in the water surface grids except the intersected grids as an end point, taking the end point as a vertical upward ray, obtaining the number of intersection points of the ray and the ocean structure grid, marking the water surface grid as an external grid when the number of the intersection points is an even number, and marking the water surface grid as an internal grid when the number of the intersection points is an odd number; and marking the water surface grids except the intersected grids in sequence, and deleting the intersected grids and the internal grids from the water surface grids after marking is finished.
The basic scheme has the following working principle and beneficial effects: and screening out the water surface grids intersected with the marine structure through the grid marking step, marking the water surface grids as intersected grids, and facilitating subsequent processing of the intersected grids through marking. The grid precision of the intersected grids is low at the moment, if the intersected grids are directly deleted, the calculation result is influenced, and meanwhile, obvious step feeling appears during post-processing display, so that the intersected grids are refined through the grid refining step, whether the refined intersected grids reach the grid precision standard or not is judged, if the refined intersected grids do not reach the standard, the grid marking step is repeated, the refined intersected grids are judged, a new intersected grid is judged again from the refined intersected grids, whether the grid precision of the refined new intersected grid reaches the standard or not is judged again, and the grid deleting step cannot be carried out until the grid precision reaches the standard. The intersected grids meet the calculation requirements at the moment, and no obvious step feeling exists during post-processing display.
In the grid deleting step, the position relation between the water surface grid and the ocean structure is judged firstly, and the position relation is divided into three position relations, namely, the water surface grid is arranged outside the ocean structure, the water surface grid is intersected with the ocean structure grid, namely, the intersected grid, and the water surface grid is arranged inside the ocean structure. Since the second, intersecting mesh, is already known, only the surface meshes other than the intersecting mesh need to be determined. Taking any point in the water surface grid as an end point to be taken as a vertical upward ray, when the ocean structure is a regular cylinder, a cube and the like, if the water surface grid is outside the ocean structure, the number of intersection points of the ray and the ocean structure grid is zero, and if the water surface grid is inside the ocean structure, the ray and the grid on the top surface of the ocean structure are intersected, and the number of the intersection points is 1. When the marine structure is irregular, such as T-shaped, if the water surface mesh is outside the marine structure, the ray passes through the left or right mesh of the T-shaped marine structure, and the number of intersection points is 2, and if the water surface mesh is inside the marine structure, the ray intersects the mesh on the top surface of the marine structure, and the number of intersection points is still 1, regardless of the structure of the marine structure, if the water surface mesh is outside the marine structure, the number of intersection points is even, and if the water surface mesh is inside the marine structure, the number of intersection points is odd. The surface mesh outside the marine structure is thus marked as an outer mesh and the surface mesh inside the marine structure is marked as an inner mesh. And deleting the internal grids and the intersecting grids to complete the quick reconstruction of the overlapped part of the water surface grids, wherein the water surface grids of the overlapped part after reconstruction can meet the calculation requirement and can not influence the grid quality of the water surface grids of other parts, thereby efficiently obtaining the high-quality water surface grids.
In the prior art, when a grid is determined to be inside or outside another grid, a method is usually adopted to perform determination according to a normal direction, obtain a normal direction of a minimum unit in the grid and a normal direction of a surface of the other grid, and determine that the minimum unit is located inside or outside the other grid according to the two normal directions. Compared with the prior art, the characteristics of surface of water net and marine structure net are combined in this application, judge through the number of crossing points, reduce the calculated amount to quick accurate judging the surface of water net, and then high-quality surface of water net is obtained to the high efficiency.
Further, the step of judging whether the water surface grid intersects with the sea structure grid in the grid marking step is as follows: and acquiring grid side lines of the water surface grid, performing line-surface intersection judgment according to the grid side lines and the ocean structure grid, and if any grid side line of the water surface grid is intersected with the ocean structure grid, intersecting the water surface grid and the ocean structure grid. Has the beneficial effects that: the method comprises the steps of obtaining grid side lines of a water surface grid, wherein one water surface grid is formed by enclosing a plurality of grid side lines, judging line-surface intersection according to the grid side lines and a sea structure grid, judging that any grid side line is intersected with any sea structure grid, considering that the water surface grid is intersected with the sea structure, and judging the water surface grid which is quickly marked and intersected with the sea structure grid through line-surface intersection.
Furthermore, the grid refining step adopts a quad-tree grid encryption method to refine the intersected grids. Has the advantages that: the mesh subdivision and intersection is realized by a quad-tree encryption mesh method, so that the purpose of smoothing the mesh is achieved.
Further, the center point of the water surface grid is taken as an end point in the grid deleting step. Has the advantages that: the whole water surface grid can be embodied by taking the central point as an end point.
Further, the method also comprises the following steps:
a grid loading step, namely reading the grid of the marine structure and the grid of the water surface and judging whether an overlapped part exists or not;
and a grid marking step, namely sequentially judging whether the water surface grid is intersected with the ocean structure grid or not when the ocean structure grid and the water surface grid have overlapped parts.
Has the advantages that: and if the overlapping part exists between the sea structure grid and the water surface grid, the subsequent steps are carried out, otherwise, the subsequent steps are not required.
Further, the step of judging whether the overlapping part exists between the ocean structure grid and the water surface grid in the grid loading step is as follows: acquiring the vertexes of the water surface meshes, acquiring the water surface depth values of the vertexes of the water surface meshes in the depth direction, and acquiring the water surface depth value with the largest numerical value as the maximum water surface depth value; obtaining the vertex of the ocean structure grid, and obtaining the depth value of the ocean structure in the depth direction of the vertex of the ocean structure grid, and obtaining the depth value of the ocean structure with the minimum value as the minimum depth value of the ocean structure; and when the maximum water surface depth value is larger than the minimum marine structure depth value, the marine structure grids and the water surface grids have an overlapping part.
Has the advantages that: and judging whether the sea structure grid and the water surface grid have an overlapping part or not by judging the maximum water surface depth value of the water surface grid in the depth direction and the minimum sea structure depth value of the sea structure grid in the depth direction.
Further, in the grid loading step, when the overlapping part exists between the ocean structure grid and the water surface grid, a binary space partition tree is created to store the water surface grid. Has the advantages that: the water surface grids are stored by adopting a structure of a binary space partition tree, so that the grid searching efficiency is improved, whether the water surface grids intersect with the ocean structure or not can be conveniently and quickly judged subsequently, and the calculation efficiency is improved.
Further, the method also comprises the following steps:
and a grid verification step, namely reading the sea structure grid, reading the water surface grid after deleting the intersected grid and the internal grid, judging whether an overlapped part exists, and if not, storing the water surface grid and the sea structure grid.
Has the advantages that: and verifying the water surface grids and the ocean structure grids to ensure that the constructed water surface grids and the constructed ocean structure grids do not have overlapping parts.
Further, in the grid verification step, a binary space partition tree is adopted to store the water surface grid and the ocean structure grid. Has the advantages that: the grid search efficiency is improved by adopting the structure storage of the binary space partition tree.
Further, in the mesh deleting step, when the number of intersection points is an odd number, a plurality of different directions are taken, a plurality of test end points are obtained by moving the end points according to the directions, the test end points are respectively used as vertically upward test rays, the number of the test intersection points of the test rays and the sea structure mesh is obtained, when even numbers exist in the number of the test intersection points, the water surface mesh is marked as an external mesh, and when no even numbers exist in the number of the test intersection points, the water surface mesh is marked as an internal mesh.
Has the beneficial effects that: the water surface mesh is judged to be an internal mesh and an external mesh based on the number of intersection points, but there is an exception, for example, one water surface mesh located outside a sea structure mesh has one number of intersection points generated by a ray of the water surface mesh and an edge of the sea structure, and in this case, the water surface mesh is misjudged as the internal mesh. In order to avoid the situation, points around the end point are obtained to be used as test end points, and further judgment is carried out according to the number of test intersection points of the test end points, so that the judgment accuracy is improved.
Drawings
FIG. 1 is a flow chart of an embodiment of the method for reconstructing an overlapping portion of a marine structure and a surface grid in accordance with the present invention;
FIG. 2 is a schematic diagram of a water surface grid and a sea structure grid according to an embodiment of the reconstruction method for the overlapping portion of the sea structure and the water surface grid;
FIG. 3 is a top view of the overlapping part of the water surface mesh and the mesh of the ocean structure according to the embodiment of the reconstruction method for the overlapping part of the ocean structure and the water surface mesh;
FIG. 4 is a top view of an intersecting mesh with one refinement according to an embodiment of the reconstruction method for an overlapping portion of a marine structure and a water surface mesh;
FIG. 5 is a top view of a water surface mesh after multiple refinements according to an embodiment of the reconstruction method for an overlapping portion of a marine structure and the water surface mesh;
fig. 6 is a top view of the water surface mesh with the intersecting mesh and the internal mesh removed according to the embodiment of the reconstruction method for the overlapping portion of the marine structure and the water surface mesh.
Detailed Description
The following is further detailed by way of specific embodiments:
examples
The reconstruction method for the overlapped part of the marine structure and the water surface grid, as shown in the attached figure 1, comprises the following steps:
the grid loading step specifically comprises the following steps:
s101: and reading the water surface grids and the sea structure grids.
S102: and acquiring the water surface mesh vertexes of the water surface mesh and the ocean structure mesh vertexes of the ocean structure mesh.
S103: and acquiring the water surface depth value of the vertex of the water surface mesh in the depth direction and the depth value of the marine structure of the vertex of the marine structure mesh in the depth direction.
S104: and sequencing the water surface depth values in a descending order, taking the water surface depth value with the largest numerical value as the largest water surface depth value, sequencing the marine structure depth values in a descending order, and taking the marine structure depth value with the smallest numerical value as the smallest marine structure depth value.
S105: judging the numerical values of the maximum water surface depth value and the minimum marine structure depth value, if the maximum water surface depth value is larger than the minimum marine structure depth value, overlapping the water surface grid and the marine structure grid, namely, one part of the marine structure is positioned above the water surface, and the other part of the marine structure is positioned below the water surface, and entering the step S106; if the maximum water surface depth value is smaller than the minimum marine structure depth value, namely the marine structure is located below the water surface, the grid loading step is repeated, and the next group of water surface grids and marine structure grids are judged. The relationship of marine structures to the surface of the water generally includes three types, the first type is that the marine structures pass through the surface of the water, i.e., one part of the marine structures is above the surface of the water, the other part is below the surface of the water, the second type is that the surface of the marine structures is flush with the surface of the water, and the third type is that the marine structures are below the surface of the water. For the second case, this generally occurs rarely, so this possibility is ignored in the present embodiment.
S106: when the water surface grid and the ocean structure grid have overlapped parts, a binary space division tree is created to store the water surface grid and the ocean structure grid, and the step of marking the grids is entered.
In this embodiment, the data to be calculated is stored in the binary space partition tree, so that the grid search efficiency is improved, and the calculation efficiency is improved.
The grid marking step specifically comprises the following steps:
s201: the method comprises the steps of obtaining grid side lines of a water surface grid and obtaining a sea structure grid, wherein one water surface grid is formed by surrounding a plurality of grid side lines, and in the embodiment, the water surface grid is formed by surrounding four grid side lines.
S202: performing line-surface intersection judgment according to the grid side line and the ocean structure grid, if the line-surface intersection judgment is performed, marking the water surface grid as an intersected grid, and acquiring the next water surface grid to enter the step S201; if the two boundary lines do not intersect, the next grid boundary line is obtained, the step S202 is repeated until the four grid boundary lines and the ocean structure grid are judged to be not intersected, the next ocean structure grid is obtained, the step S202 is repeated until the water surface grid and all the ocean structure grids are judged to be not intersected, the next water surface grid is obtained, the step S201 is carried out, and the grid refining step is carried out after all the water surface grids are obtained.
In this embodiment, any one water surface grid is taken to sequentially judge whether the water surface grid intersects with all the ocean structure grids, and after the judgment is completed, one water surface grid is taken down to sequentially judge whether the water surface grid intersects with all the ocean structure grids, and different water surface grids are taken sequentially for judgment. In other embodiments, any one of the ocean structure grids may be used to sequentially determine whether the grid intersects with all the water surface grids, and after the determination is completed, the next ocean structure grid is taken to sequentially determine whether the grid intersects with all the water surface grids, and different ocean structure grids are sequentially taken to perform the determination.
In other embodiments, the ocean structure grid can also be stored by adopting a point-line-plane-unit data structure, the three-dimensional space is divided according to a specified resolution, and if the bounding box of the grid edge line of the ocean structure grid is not in the water surface grid, the intersection of the bounding box and the water surface grid can be judged, so that whether the water surface grid and the ocean structure grid are intersected or not can be quickly judged.
In this embodiment, the water surface grid is a quadrangle, such as a square or a rectangle, and the grid refining step specifically includes the following steps:
s301: an intersecting grid is obtained.
S302: and refining the intersected grids by adopting a quad-tree encryption grid method, and reconstructing a topological structure. In the embodiment, the water surface grids conform to a rule of four, so that the intersected grids are refined by adopting a quad-tree grid encryption method, and the refinement of the grids is efficiently completed.
S303: judging whether the grid precision of the refined intersected grids reaches the standard or not, and entering a grid deleting step when the refined intersected grids meet the calculation requirement and no obvious step feeling exists in post-processing display (the calculation requirement and whether no obvious step feeling exists can be artificially confirmed or corresponding indexes can be artificially uploaded for judgment, such as the size of each grid, in the embodiment, the latter type is preferred), namely the grid reaches the standard; otherwise, the grid marking step is entered (i.e. the grid marking step and the grid refinement step are repeated).
The grid deleting step specifically comprises the following steps:
s401: water surface grids are obtained except for grids marked as intersecting grids, the water surface grids are divided into grids marked as intersecting grids and grids which are not marked, and the water surface grids obtained at the moment are not marked.
S402: taking any point in the water surface grid as an end point, and taking the end point as a vertical upward ray. In this embodiment, the center point of the water surface grid is used as the end point.
S403: acquiring the number of intersection points of the rays and the ocean structure grids, and marking the water surface grids as external grids when the number of the intersection points is an even number (including when the number of the intersection points is zero); when the number of the intersection points is an odd number, the side length of one water surface grid is defined as a unit length (when the water surface grid is a rectangle, the shorter side length of the water surface grid is defined as a unit length), one tenth of the unit length is taken as a test length, the end point is taken as an original point, four mutually perpendicular directions are taken, such as the front, the back, the left and the right of the end point, the end point is respectively moved according to four directions to obtain four test end points, the four test end points are taken as vertical upward rays as test rays, the test intersection points of the test rays and the sea structure grid are respectively obtained, the total number of the four test intersection points is four, when an even number exists in the four test intersection points, the water surface grid is marked as an external grid, and when the even number does not exist in the four test intersection points, the water surface grid is marked as an internal grid; and acquiring the next water surface grid after marking, and entering the step S402 until all the water surface grids except the grid marked as the intersection grid are marked, and entering the step S404. The marks of the water surface grids are three types at this time, including an intersecting grid, an internal grid and an external grid.
S404: and deleting the water surface grids marked as the internal grids and the intersected grids, completing the grid reconstruction of the overlapped part of the water surface grids, and entering a grid verification step.
The grid verification step specifically comprises the following steps:
s501: obtaining the water surface mesh with the cross mesh and the internal mesh deleted as a new water surface mesh, and obtaining the sea structure mesh,
s502: and acquiring new water surface grid vertexes of the new water surface grids and ocean structure grid vertexes of the ocean structure grids.
S503: and acquiring a new water surface depth value of the new water surface grid vertex in the depth direction and an ocean structure depth value of the ocean structure grid vertex in the depth direction.
S504: and sequencing the new water surface depth values in a descending order, taking the new water surface depth value with the largest value as the largest new water surface depth value, sequencing the marine structure depth values in a descending order, and taking the marine structure depth value with the smallest value as the smallest marine structure depth value.
S505: judging the numerical values of the maximum new water surface depth value and the minimum marine structure depth value, if the maximum new water surface depth value is larger than the minimum marine structure depth value, overlapping the new water surface grid and the marine structure grid, and entering the step S506; and if the maximum new water surface depth value is smaller than the minimum marine structure depth value, storing the new water surface grid and the marine structure grid by adopting a binary space partition tree, and acquiring the topological structure of the new water surface grid and the topological structure of the marine structure grid to generate a new topological structure.
S506: and taking the new water surface grid as a water surface grid, creating a binary space partition tree to store the water surface grid and the ocean structure grid, and entering a grid marking step.
In the present embodiment, a description is given by way of a specific example. The water surface mesh and the sea structure mesh with the overlapped part are obtained through the mesh loading step, and the mesh loading step is shown in the attached figure 2. The overlapping part of the marine structure and the surface mesh is shown in fig. 3.
After the grid marking step and the grid thinning step, as shown in fig. 4, it is obvious from fig. 4 that the intersected grids are large, if the intersected grids are directly deleted, the calculation result is influenced, and meanwhile, obvious step feeling appears during post-processing display. The grid marking step and the grid refinement step are thus repeated 3 to 10 times, in this embodiment 4 times, as shown in fig. 5.
And deleting the intersected grids and the internal grids through a grid deleting step to obtain a new water surface grid, as shown in the attached figure 6.
The foregoing is merely an example of the present invention, and common general knowledge in the field of known specific structures and characteristics is not described herein in any greater extent than that known in the art at the filing date or prior to the priority date of the application, so that those skilled in the art can now appreciate that all of the above-described techniques in this field and have the ability to apply routine experimentation before this date can be combined with one or more of the present teachings to complete and implement the present invention, and that certain typical known structures or known methods do not pose any impediments to the implementation of the present invention by those skilled in the art. It should be noted that, for those skilled in the art, without departing from the structure of the present invention, several changes and modifications can be made, which should also be regarded as the protection scope of the present invention, and these will not affect the effect of the implementation of the present invention and the practicability of the patent. The scope of the claims of the present application shall be defined by the claims, and the description of the embodiments and the like in the specification shall be used to explain the contents of the claims.
Claims (9)
1. The reconstruction method for the overlapped part of the marine structure and the water surface grid is characterized by comprising the following steps of:
a step of marking grids, which is to sequentially judge whether the water surface grids intersect with the grids of the ocean structure, and mark the water surface grids as intersecting grids if the water surface grids intersect with the grids of the ocean structure;
a grid refining step, namely refining the intersected grids, judging whether the grid precision of the refined intersected grids reaches the standard or not, and if not, repeating the grid marking step and the grid refining step;
a grid deleting step, when the grid precision of the thinned intersected grid is up to standard, taking any point in the water surface grid except the intersected grid as an end point, taking the end point as a vertically upward ray, obtaining the number of intersection points of the ray and the sea structure grid, when the number of the intersection points is an even number, marking the water surface grid as an external grid, when the number of the intersection points is an odd number, taking a plurality of different directions, moving the end point according to the directions to obtain a plurality of test end points, respectively taking the test end point as a vertically upward test ray, obtaining the number of the test intersection points of the test ray and the sea structure grid, when the number of the test intersection points is even, marking the water surface grid as an external grid, and when the number of the test intersection points is not even, marking the water surface grid as an internal grid; and marking the water surface grids except the intersected grids in sequence, and deleting the intersected grids and the internal grids from the water surface grids after marking is finished.
2. The method as claimed in claim 1, wherein the step of determining whether the water surface mesh intersects with the sea structure mesh in the mesh marking step comprises: and acquiring grid side lines of the water surface grid, performing line-surface intersection judgment according to the grid side lines and the ocean structure grid, and if any grid side line of the water surface grid is intersected with the ocean structure grid, intersecting the water surface grid and the ocean structure grid.
3. The reconstruction method for the overlapping portion of the marine structure and the water surface mesh according to claim 1, wherein: and in the grid refining step, a quad-tree encryption grid method is adopted to refine the intersected grids.
4. The reconstruction method for the overlapping portion of the marine structure and the water surface mesh according to claim 1, wherein: and in the grid deleting step, the central point of the water surface grid is taken as an end point.
5. The reconstruction method for the overlapping portion of the marine structure and the water surface mesh according to claim 1, 2 or 4, further comprising the steps of:
a grid loading step, namely reading the grid of the marine structure and the grid of the water surface, and judging whether an overlapping part exists or not;
and a grid marking step, namely sequentially judging whether the water surface grid is intersected with the ocean structure grid or not when the ocean structure grid and the water surface grid have overlapped parts.
6. The reconstruction method for the overlapping portion of the sea structure grid and the water surface grid according to claim 5, wherein the step of determining whether the overlapping portion exists between the sea structure grid and the water surface grid in the grid loading step is: acquiring the top points of the water surface meshes, and acquiring the water surface depth value of the top points of the water surface meshes in the depth direction, and acquiring the water surface depth value with the largest numerical value as the maximum water surface depth value; obtaining the vertex of the ocean structure grid, and obtaining the depth value of the ocean structure in the depth direction of the vertex of the ocean structure grid, and obtaining the depth value of the ocean structure with the minimum value as the minimum depth value of the ocean structure; and when the maximum water surface depth value is larger than the minimum marine structure depth value, the marine structure grids and the water surface grids have an overlapping part.
7. The method of claim 6, wherein the step of reconstructing the overlapping portion of the marine structure and the water surface mesh comprises: and in the grid loading step, when the overlapping part exists between the ocean structure grid and the water surface grid, creating a binary space partition tree to store the water surface grid.
8. The method of reconstructing an overlapping portion of a marine structure and a water surface mesh of claim 7, further comprising the steps of:
and a grid verification step, namely reading the sea structure grid, reading the water surface grid after deleting the intersected grid and the internal grid, judging whether an overlapped part exists, and if not, storing the water surface grid and the sea structure grid.
9. The method of claim 8, wherein the step of reconstructing the overlapping portion of the marine structure and the surface mesh comprises: and in the grid verification step, a binary space partition tree is adopted to store the water surface grid and the ocean structure grid.
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Citations (2)
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