Tidying/commenting.

This commit is contained in:
David Williams 2014-06-01 17:35:00 +02:00
parent 392ccab703
commit b259b60de2
2 changed files with 18 additions and 0 deletions

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@ -47,6 +47,8 @@ namespace PolyVox
Vector3DUint8 position;
uint8_t normal;
// User data
DataType data;
};

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@ -44,11 +44,19 @@ namespace PolyVox
{
typedef _DataType DataType;
// Each component of the position is stored using 8.8 fixed-point encoding.
Vector3DUint16 position;
// Each component of the normal is encoded using 5 bits of this variable.
// The 16 bits are -xxxxxyyyyyzzzzz (note the left-most bit is currently
// unused). Some extra shifting and scaling is required to make it signed.
uint16_t normal;
// User data
DataType data;
};
/// Decodes a position from a MarchingCubesVertex
Vector3DFloat decode(const Vector3DUint16& position)
{
Vector3DFloat result(position.getX(), position.getY(), position.getZ());
@ -56,19 +64,27 @@ namespace PolyVox
return result;
}
/// Decodes a normal from a MarchingCubesVertex
Vector3DFloat decode(const uint16_t normal)
{
// Get normal components in the range 0 to 31
uint16_t x = (normal >> 10) & 0x1F;
uint16_t y = (normal >> 5) & 0x1F;
uint16_t z = (normal) & 0x1F;
// Build the resulting vector
Vector3DFloat result(x, y, z);
// Convert to range 0.0 to 2.0
result *= (1.0f / 15.5f); // Division is compile-time constant
// Convert to range -1.0 to 1.0
result -= Vector3DFloat(1.0f, 1.0f, 1.0f);
return result;
}
/// Decodes a MarchingCubesVertex by converting it into a regular Vertex which can then be directly used for rendering.
template<typename DataType>
Vertex<DataType> decode(const MarchingCubesVertex<DataType>& marchingCubesVertex)
{