NAME

RTC_GEOMETRY_TYPE_GRID - grid geometry type

    

SYNOPSIS

#include <embree3/rtcore.h>
RTCGeometry geometry =
  rtcNewGeometry(device, RTC_GEOMETRY_TYPE_GRID);

    

DESCRIPTION

The vertex buffer contains an array of single precision x, y, z floating point coordinates (RTC_FORMAT_FLOAT3 format), and the number of vertices is inferred from the size of that buffer.

Each grid in the grid buffer is of the type RTCGrid:

struct RTCGrid
{
  unsigned int startVertexID;
  unsigned int stride;
  unsigned short width,height; 
};

    

The RTCGrid structure describes a 2D grid of vertices (with respect to the vertex buffer of the grid mesh). The width and height members specify the number of vertices in u and v direction, e.g. setting both width and height to 3 sets up a 3×3 vertex grid. The maximum allowed width and height is 32767. The startVertexID specifies the ID of the top-left vertex in the vertex grid, while the stride parameter specifies a stride (in number of vertices) used to step to the next row.

A vertex grid of dimensions width and height is treated as a (width-1) x (height-1) grid of quads (triangle-pairs), with the same shared edge handling as for regular quad meshes. However, the u/v coordinates have the uniform range [0..1] for an entire vertex grid. The u direction follows the width of the grid while the v direction the height.

For multi-segment motion blur, the number of time steps must be first specified using the rtcSetGeometryTimeStepCount call. Then a vertex buffer for each time step can be set using different buffer slots, and all these buffers must have the same stride and size.

EXIT STATUS

SEE ALSO