Method for forming an optimized polygon based shell mesh

An image processing apparatus for forming an optimized polygon based mesh for a three-dimensional graphics image, to be used as an occluder mesh and an occludee mesh in a visual simulation, comprising:

• a processor configured to,
• obtain the three-dimensional graphics image, the three-dimensional graphics image represented as an initial polygon mesh,
• determine a three-dimensional profile of the initial polygon mesh by determining a view independent silhouette of the initial polygon mesh,
• resize the initial polygon mesh a predetermined amount along a line normal to the three-dimensional profile of the initial polygon mesh, so as to form a first resized polygon mesh having a three-dimensional profile that is a predetermined amount larger than the three-dimensional profile of the initial polygon mesh,
• form the occludee mesh by adjusting the three-dimensional profile of the first resized polygon mesh using a polygon optimization process such that a desired majority of the occludee mesh encloses the three-dimensional profile of the initial polygon mesh, wherein the occludee mesh comprises fewer polygons than the initial polygon mesh,
• use the occludee mesh to determine polygon visibility within a scene to be displayed,
• resize the initial polygon mesh a predetermined amount along a line normal to the three-dimensional profile of the initial polygon mesh, so as to form a second resized polygon mesh having a three-dimensional profile that is a predetermined amount smaller than the three-dimensional profile of the initial polygon mesh,
• form the occluder mesh by adjusting the three-dimensional profile of the second resized polygon mesh using a polygon optimization process such that a desired majority of the occluder mesh is enclosed by the three-dimensional profile of the initial polygon mesh, wherein the occluder mesh comprises fewer polygons than the initial polygon mesh, and
• use the occluder mesh to determine polygon visibility within the scene to be displayed.

A computer product comprising a non-transitory computer readable medium having stored thereon a computer program product for controlling an image processing apparatus configured for forming an occluder mesh and an occludee mesh for a three-dimensional graphics image, wherein, when executed, the computer program product causes the image processing apparatus to perform operations comprising:

• obtaining the three-dimensional graphics image, the three-dimensional graphics image represented as an initial polygon mesh;
• determining a three-dimensional profile of the initial polygon mesh by determining a view independent silhouette of the initial polygon mesh;
• resizing the initial polygon mesh a predetermined amount along a line normal to the three-dimensional profile of the initial polygon mesh, so as to form a first resized polygon mesh having a three-dimensional profile that is larger than the three-dimensional profile of the initial polygon mesh;
• forming the occludee mesh by adjusting the three-dimensional profile of the first resized polygon mesh using a polygon optimization process such that a desired majority of the occludee mesh encloses the three-dimensional profile of the initial polygon mesh, wherein the occludee mesh comprises fewer polygons than the initial polygon mesh;
• using the occludee mesh to determine polygon visibility within a scene to be displayed;
• resizing the initial polygon mesh a predetermined amount along a line normal to the three-dimensional profile of the initial polygon mesh, so as to form a second resized polygon mesh having a three-dimensional profile that is a predetermined amount smaller than the three-dimensional profile of the initial polygon mesh;
• forming the occluder mesh by adjusting the three-dimensional profile of the second resized polygon mesh using a polygon optimization process such that a desired majority of the occluder mesh is enclosed by the three-dimensional profile of the initial polygon mesh, wherein the occluder mesh comprises fewer polygons than the initial polygon mesh;
• and
• using the occluder mesh to determine polygon visibility within the scene to be displayed.