OpenCascade/occt
1
0
Fork 0
mirror of https://git.dev.opencascade.org/repos/occt.git synced 2025-04-05 18:16:23 +03:00
Code Packages Releases Activity

0025760: Visualization - precision factor added to ZNear, ZFar in method ZFitAll() of Graphic3d_Camera is not enough

Browse Source 
Partial fix: increased epsilon to value reported in #0025670
This commit is contained in:
apl 2015-05-07 15:00:23 +03:00 committed by abv
parent 30a7308729
commit 35c4a17c46
1 changed files with 25 additions and 31 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

56
src/Graphic3d/Graphic3d_Camera.cxx
View File

@ -986,29 +986,27 @@ void Graphic3d_Camera::ZFitAll (const Standard_Real theScaleFactor, const Bnd_Bo
// fixed using tolerance distance, relative to boundaries size. The tolerance distance // fixed using tolerance distance, relative to boundaries size. The tolerance distance
// should be computed using information on boundaries of primary application actors, // should be computed using information on boundaries of primary application actors,
// (e.g. representing the displayed model) - to ensure that they are not unreasonably clipped. // (e.g. representing the displayed model) - to ensure that they are not unreasonably clipped.
const Standard_ShortReal anEpsilon = 1e-4;
if (theGraphicBB.IsVoid()) if (theGraphicBB.IsVoid())
{ {
// ShortReal precision factor used to add meaningful tolerance to // Precision factor used to add meaningful tolerance to
// ZNear, ZFar values in order to avoid equality after type conversion // ZNear, ZFar values in order to avoid equality after type conversion
// to ShortReal matrices type. // to ShortReal matrices type.
const Standard_Real aPrecision = 1.0 / Pow (10.0, ShortRealDigits() - 1);
Standard_Real aZFar = Distance() * 3.0; Standard_Real aZFar = Distance() * 3.0;
Standard_Real aZNear = 0.0; Standard_Real aZNear = 0.0;
if (!IsOrthographic()) if (!IsOrthographic())
{ {
if (aZFar < aPrecision) if (aZFar < anEpsilon)
{ {
// Invalid case when both values are negative aZNear = anEpsilon;
aZNear = aPrecision; aZFar = anEpsilon * 2.0;
aZFar = aPrecision * 2.0;
} }
else if (aZNear < Abs (aZFar) * aPrecision) else if (aZNear < aZFar * anEpsilon)
{ {
// Z is less than 0.0, try to fix it using any appropriate z-scale aZNear = aZFar * anEpsilon;
aZNear = Abs (aZFar) * aPrecision;
} }
} }
@ -1090,22 +1088,20 @@ void Graphic3d_Camera::ZFitAll (const Standard_Real theScaleFactor, const Bnd_Bo
Standard_Real aMidDepth = (aGraphicMinDist + aGraphicMaxDist) * 0.5; Standard_Real aMidDepth = (aGraphicMinDist + aGraphicMaxDist) * 0.5;
Standard_Real aHalfDepth = (aGraphicMaxDist - aGraphicMinDist) * 0.5; Standard_Real aHalfDepth = (aGraphicMaxDist - aGraphicMinDist) * 0.5;
// ShortReal precision factor used to add meaningful tolerance to
// ZNear, ZFar values in order to avoid equality after type conversion
// to ShortReal matrices type.
const Standard_Real aPrecision = Pow (0.1, ShortRealDigits() - 2);
// Compute enlarged or shrank near and far z ranges // Compute enlarged or shrank near and far z ranges
Standard_Real aZNear = aMidDepth - aHalfDepth * theScaleFactor; Standard_Real aZNear = aMidDepth - aHalfDepth * theScaleFactor;
Standard_Real aZFar = aMidDepth + aHalfDepth * theScaleFactor; Standard_Real aZFar = aMidDepth + aHalfDepth * theScaleFactor;
aZNear -= aPrecision * 0.5; Standard_Real aZRange = Abs (aZFar - aZNear);
aZFar += aPrecision * 0.5; Standard_Real aZConf = Max (static_cast <Standard_Real> (anEpsilon * aZRange),
static_cast <Standard_Real> (anEpsilon));
aZNear -= Abs (aZNear) * anEpsilon + aZConf;
aZFar += Abs (aZFar) * anEpsilon + aZConf;
if (!IsOrthographic()) if (!IsOrthographic())
{ {
if (aZFar >= aPrecision) if (aZFar > anEpsilon)
{ {
// To avoid numeric errors... (See comments in the beginning of the method).
// Choose between model distance and graphical distance, as the model boundaries // Choose between model distance and graphical distance, as the model boundaries
// might be infinite if all structures have infinite flag. // might be infinite if all structures have infinite flag.
const Standard_Real aGraphicDepth = aGraphicMaxDist >= aGraphicMinDist const Standard_Real aGraphicDepth = aGraphicMaxDist >= aGraphicMinDist
@ -1115,25 +1111,23 @@ void Graphic3d_Camera::ZFitAll (const Standard_Real theScaleFactor, const Bnd_Bo
? aModelMaxDist - aModelMinDist : RealLast(); ? aModelMaxDist - aModelMinDist : RealLast();
const Standard_Real aMinDepth = Min (aModelDepth, aGraphicDepth); const Standard_Real aMinDepth = Min (aModelDepth, aGraphicDepth);
const Standard_Real aZTolerance = const Standard_Real aZTol = Max (static_cast<Standard_Real> (anEpsilon * Abs (aMinDepth)),
Max (Abs (aMinDepth) * aPrecision, aPrecision); static_cast<Standard_Real> (anEpsilon));
if (aZNear < aZTol)
if (aZNear < aZTolerance)
{ {
aZNear = aZTolerance; aZNear = aZTol;
} }
} }
else // aZFar < aPrecision - Invalid case when both ZNear and ZFar are negative else
{ {
aZNear = aPrecision; aZNear = anEpsilon;
aZFar = aPrecision * 2.0; aZFar = anEpsilon * 2.0;
} }
} }
// If range is too small if (aZFar < (aZNear + Abs (aZFar) * anEpsilon))
if (aZFar < (aZNear + Abs (aZFar) * aPrecision))
{ {
aZFar = aZNear + Abs (aZFar) * aPrecision; aZFar = aZNear + Abs (aZFar) * anEpsilon;
} }
SetZRange (aZNear, aZFar); SetZRange (aZNear, aZFar);