/// <summary>
/// Copy from an ArrayBufferObject with an indirection defined by an index.
/// </summary>
/// <param name="buffer">
/// An <see cref="ArrayBufferObject"/> that specify the source data buffer to copy.
/// </param>
/// <param name="indices">
/// An array of indices indicating the order of the vertices copied from <paramref name="buffer"/>.
/// </param>
/// <param name="count">
/// A <see cref="UInt32"/> that specify how many elements to copy from <paramref name="buffer"/>.
/// </param>
/// <param name="offset">
/// A <see cref="UInt32"/> that specify the first index considered from <paramref name="indices"/>. A
/// value of 0 indicates that the indices are considered from the first one.
/// </param>
/// <param name="stride">
/// A <see cref="UInt32"/> that specify the offset between two indexes considered for the copy operations
/// from <paramref name="indices"/>. A value of 1 indicates that all considered indices are contiguos.
/// </param>
/// <exception cref="ArgumentNullException">
/// Exception thrown if <paramref name="buffer"/> or <paramref name="indices"/> are null.
/// </exception>
/// <exception cref="ArgumentException">
/// Exception thrown if <paramref name="count"/> or <paramref name="stride"/> equals to 0.
/// </exception>
/// <exception cref="InvalidOperationException">
/// Exception thrown if the combination of <paramref name="count"/>, <paramref name="offset"/> and
/// <paramref name="stride"/> will cause a <paramref name="indices"/> array access out of its bounds.
/// </exception>
/// <exception cref="InvalidOperationException">
/// Exception thrown if this <see cref="ArrayBufferObject"/> have a complex data layout, of it has a vertex
/// base type different from <paramref name="buffer"/>.
/// </exception>
/// <remarks>
/// <para>
/// After a successfull copy operation, the previous buffer is discarded replaced by the copied buffer from
/// <paramref name="buffer"/>.
/// </para>
/// </remarks>
public void Copy(ArrayBufferObject buffer, uint[] indices, uint count, uint offset, uint stride)
{
if (buffer == null)
{
throw new ArgumentNullException("buffer");
}
if (indices == null)
{
throw new ArgumentNullException("indices");
}
if (count == 0)
{
throw new ArgumentException("invalid", "count");
}
if (stride == 0)
{
throw new ArgumentException("invalid", "stride");
}
if (offset + ((count - 1) * stride) > indices.Length)
{
throw new InvalidOperationException("indices out of bounds");
}
if (ArrayBufferItem.GetArrayBaseType(_ArrayType) != ArrayBufferItem.GetArrayBaseType(buffer._ArrayType))
{
throw new InvalidOperationException("base type mismatch");
}
Create(count);
unsafe {
byte *dstPtr = (byte *)ClientBufferAddress.ToPointer();
for (uint i = 0; i < count; i++, dstPtr += ItemSize)
{
uint arrayIndex = indices[(i * stride) + offset];
// Position 'srcPtr' to the indexed element
byte *srcPtr = ((byte *)buffer.ClientBufferAddress.ToPointer()) + (ItemSize * arrayIndex);
// Copy the 'arrayIndex'th element
Memory.MemoryCopy(dstPtr, srcPtr, ItemSize);
}
}
}
/// <summary>
/// Copy from an ArrayBufferObject with an indirection defined by an index (polygon tessellation).
/// </summary>
/// <param name="buffer"></param>
/// <param name="indices"></param>
/// <param name="count"></param>
/// <param name="offset"></param>
/// <param name="stride"></param>
public void Copy(ArrayBufferObject buffer, ElementBufferObject indices, uint count, uint offset, uint stride)
{
uint[] indicesArray;
switch (indices.ElementsType)
{
case DrawElementsType.UnsignedByte:
indicesArray = Array.ConvertAll <byte, uint>((byte[])indices.ToArray(), delegate(byte item) { return((uint)item); });
break;
case DrawElementsType.UnsignedShort:
indicesArray = Array.ConvertAll <ushort, uint>((ushort[])indices.ToArray(), delegate(ushort item) { return((uint)item); });
break;
case DrawElementsType.UnsignedInt:
indicesArray = (uint[])indices.ToArray();
break;
default:
throw new InvalidOperationException(String.Format("element type {0} not supportted", indices.ElementsType));
}
Copy(buffer, indicesArray, count, offset, stride);
}
/// <summary>
/// Copy from an ArrayBufferObject with an indirection defined by an index (polygon tessellation).
/// </summary>
/// <param name="buffer"></param>
/// <param name="indices"></param>
/// <param name="count"></param>
public void Copy(ArrayBufferObject buffer, ElementBufferObject indices, uint count)
{
Copy(buffer, indices, count, 0, 1);
}
/// <summary>
/// Copy from an ArrayBufferObject with an indirection defined by an index (polygon tessellation).
/// </summary>
/// <param name="buffer">
/// An <see cref="ArrayBufferObject"/> that specify the source data buffer to copy.
/// </param>
/// <param name="vcount">
/// An array of integers indicating the number of the vertices of the polygon copied from <paramref name="buffer"/>. This parameter
/// indicated how many polygons to copy (the array length). Each item specify the number of vertices composing the polygon.
/// </param>
/// <param name="indices">
/// An array of indices indicating the order of the vertices copied from <paramref name="buffer"/>.
/// </param>
/// <param name="offset">
/// A <see cref="UInt32"/> that specify the first index considered from <paramref name="indices"/>. A
/// value of 0 indicates that the indices are considered from the first one.
/// </param>
/// <param name="stride">
/// A <see cref="UInt32"/> that specify the offset between two indexes considered for the copy operations
/// from <paramref name="indices"/>. A value of 1 indicates that all considered indices are contiguos.
/// </param>
/// <exception cref="ArgumentNullException">
/// Exception thrown if <paramref name="buffer"/>, <paramref name="indices"/> or <paramref name="vcount"/> are null.
/// </exception>
/// <exception cref="InvalidOperationException">
/// Exception thrown if this <see cref="ArrayBufferObject"/> have a complex data layout, of it has a vertex
/// base type different from <paramref name="buffer"/>.
/// </exception>
/// <remarks>
/// <para>
/// After a successfull copy operation, the previous buffer is discarded replaced by the copied buffer from
/// <paramref name="buffer"/>.
/// </para>
/// </remarks>
public void Copy(ArrayBufferObject buffer, uint[] indices, uint[] vcount, uint offset, uint stride)
{
if (buffer == null)
{
throw new ArgumentNullException("buffer");
}
if (indices == null)
{
throw new ArgumentNullException("indices");
}
if (vcount == null)
{
throw new ArgumentNullException("indices");
}
if (stride == 0)
{
throw new ArgumentException("invalid", "stride");
}
if (ArrayBufferItem.GetArrayBaseType(_ArrayType) != ArrayBufferItem.GetArrayBaseType(buffer._ArrayType))
{
throw new InvalidOperationException("base type mismatch");
}
// Allocate array buffer
uint minVertices = UInt32.MaxValue, maxVertices = UInt32.MinValue;
Array.ForEach(vcount, delegate(uint v) {
minVertices = Math.Min(v, minVertices);
maxVertices = Math.Max(v, maxVertices);
});
if ((minVertices < 3) && (maxVertices >= 3))
{
throw new ArgumentException("ambigous polygons set", "vcount");
}
uint totalVerticesCount = 0;
Array.ForEach(vcount, delegate(uint v) {
if (v == 4)
{
totalVerticesCount += 6; // Triangulate quad with two triangles
}
else if (v > 4)
{
totalVerticesCount += (v - 2) * 3; // Triangulate as if it is a polygon
}
else
{
Debug.Assert(v == 3);
totalVerticesCount += 3; // Exactly a triangle
}
});
Create(totalVerticesCount);
// Copy polygons (triangulate)
uint count = 0;
unsafe {
byte *dstPtr = (byte *)ClientBufferAddress.ToPointer();
uint indicesIndex = offset;
for (uint i = 0; i < vcount.Length; i++)
{
uint verticesCount = vcount[i];
uint[] verticesIndices;
if (verticesCount == 4)
{
verticesIndices = new uint[6];
verticesIndices[0] = indices[indicesIndex + (0 * stride)];
verticesIndices[1] = indices[indicesIndex + (1 * stride)];
verticesIndices[2] = indices[indicesIndex + (2 * stride)];
verticesIndices[3] = indices[indicesIndex + (0 * stride)];
verticesIndices[4] = indices[indicesIndex + (2 * stride)];
verticesIndices[5] = indices[indicesIndex + (3 * stride)];
indicesIndex += 4 * stride;
}
else if (verticesCount > 4)
{
uint triCount = verticesCount - 2;
uint pivotIndex = indicesIndex;
verticesIndices = new uint[triCount * 3];
// Copy polygon indices
for (uint tri = 0; tri < triCount; tri++)
{
verticesIndices[tri * 3 + 0] = indices[pivotIndex];
verticesIndices[tri * 3 + 1] = indices[indicesIndex + (tri + 2) * stride];
verticesIndices[tri * 3 + 2] = indices[indicesIndex + (tri + 1) * stride];
}
indicesIndex += verticesCount * stride;
}
else
{
verticesIndices = new uint[verticesCount];
for (int j = 0; j < verticesCount; j++, indicesIndex += stride)
{
verticesIndices[j] = indices[indicesIndex];
}
}
count += (uint)verticesIndices.Length;
for (uint j = 0; j < verticesIndices.Length; j++, dstPtr += ItemSize)
{
// Position 'srcPtr' to the indexed element
byte *srcPtr = ((byte *)buffer.ClientBufferAddress.ToPointer()) + (ItemSize * verticesIndices[j]);
// Copy the 'arrayIndex'th element
Memory.MemoryCopy(dstPtr, srcPtr, ItemSize);
}
}
}
}