DvSetRadiosityConvergence(3D)

NAME
DvSetRadiosityConvergence - Set the radiosity convergence criterion for a view

SYNOPSIS
C:
void DvSetRadiosityConvergence(view, type, parms)
DtObject view ;
DtRadiosityConvType type;
DtReal parms[];

FORTRAN:
CALL DVSRDC(VIEW,TYPE,PARMS)
INTEGER*4 VIEW
INTEGER*4 TYPE
REAL*8 PARMS(*)

DESCRIPTION
DvSetRadiosityConvergence sets the radiosity convergence criterion for a view. This applies to progressive radiosity techniques in which intermediate images are computed until a certain criterion or threshold is met. Possible type values are:

DcConvFixedIterations <DCCVFI>
    Perform a fixed number of iterations specified in parms[0].

DcConvGlobalRel <DCCVGR>
    Stop when the ratio of the total unshot energy over the total energy in the scene is smaller or equal to parms[0].

DcConvGlobalAbs <DCCVGA>
    Stop when the total unshot energy in the scene is smaller or equal to parms[0].

DcConvPatchRel <DCCVPR>
    Stop when the ratio of the unshot energy of the brightest patch over the total energy in the scene is smaller or equal to parms[0]. The brightest patch is the patch with the maximum unshot energy.

DcConvPatchAbs <DCCVPA>
    Stop when the unshot energy of the brightest patch in the scene is smaller or equal to parms[0].

The initial scene displays the emissive objects with some intensity, and the rest of the objects as black. During this first iteration, the total energy in the scene is computed as:

       Sum Emission(i) * EmissionFactor(i) * area(i)
        i

for all patches i. This sum is computed on a channel basis (r,g,b) and the three values are summed to get the total energy. After every iteration, the total unshot energy is computed, and the unshot energy of the brightest patch is recorded. The iterative process stops whenever the criteria is met, or when the unshort energy in the scene drops below 1e-10. If the total unshot energy in the scene drops below a negligible amount, the solution is complete and is equivalent to the one resulting from using a non-progressive radiosity algorithm.

ERRORS
DvSetRadiosityConvergence will fail if the view handle is invalid.

[WARNING - invalid view handle]

DEFAULTS
The default convergence type is DcConvGlobalRel <DCCVGR> with parms[0] equals to 0.1 (below ten percent of the global energy remains to be shot).

SEE ALSO
DvInqRadiosityConvergence(3D), DoRadiositySwitch(3D), DoIntermediateDispType(3D)