selfshadow

realtime rendering v3 page 351

Moire pattern

sruface acne

artifacts

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用 setstate

dx

depthslopescalebias

depthbias

gl

setPolygonOffset(depthslopescalebias,depthbias,clamp)

depthslopescalebias 

depthbias经验值，。。。。。wip

/// The offset is computed by multiplying the maximum depth slope of
/// the primitive [sqrt((dz/dx)^2 + (dz/dy)^2)] by _factor_, adding in
/// the minimum resolvable difference in depth values multiplied by
/// _units_, and clamping the result as described in the documentation
/// for _clamp_.

/// param factor Value multiplied by the maximum depth slope when
/// computing offset.
///
/// param units Value multiplied by the minimum resolvable depth
/// difference when computing offset.
///
/// param clamp Value used to clamp the computed offset.
/// If `clamp` is positive, the computed depth offset will be clamped
/// to a value less than or equal to `clamp`. If `clamp` is negative,
/// the computed depth offset will be clamped to a value greater than
/// or equal to `clamp`. If `clamp` is zero, the computed depth offset
/// will not be clamped.

void SetPolygonOffsetClamp(float factor,
float units,
float clamp);