/// <summary>
/// Reads vertices from a vertex buffer.
/// </summary>
/// <param name="reader">The stream to read from.</param>
/// <param name="layout">The layout of each vertex to read.</param>
/// <param name="count">The number of vertices to read.</param>
/// <param name="boundingBox">The bounding box to transform vertices with. Can be null.</param>
/// <param name="processor">The IVertexProcessor to send read vertices to. Can be null.</param>
public static void ReadVertices(IReader reader, VertexLayout layout, int count, IModelBoundingBox boundingBox, IVertexProcessor processor)
{
for (int i = 0; i < count; i++)
{
long vertexStartPos = reader.Position;
if (processor != null)
processor.BeginVertex();
foreach (VertexElementLayout element in layout.Elements)
{
if (element.Stream == 0) // Not sure how multistream vertices work yet
{
reader.SeekTo(vertexStartPos + element.Offset);
ReadElement(reader, element, boundingBox, processor);
}
}
if (processor != null)
processor.EndVertex();
}
}
/// <summary>
/// Reads the vertex buffer for a section in a model.
/// </summary>
/// <param name="reader">The stream to read the vertex buffer from.</param>
/// <param name="section">The model section that the vertex buffer belongs to.</param>
/// <param name="buildInfo">Information about the cache file's target engine.</param>
/// <param name="boundingBox">The bounding box for the model section.</param>
/// <param name="processor">The IModelProcessor to pass the read model data to, or null if the vertex buffer should be skipped over.</param>
private static void ReadSectionVertices(IReader reader, IModelSection section, IModelBoundingBox boundingBox, BuildInformation buildInfo, IModelProcessor processor)
{
VertexLayout layout = buildInfo.VertexLayouts.GetLayout(section.VertexFormat);
foreach (IModelSubmesh submesh in section.Submeshes)
{
if (processor != null)
processor.BeginSubmeshVertices(submesh);
VertexBufferReader.ReadVertices(reader, layout, submesh.VertexBufferCount, boundingBox, processor);
if (processor != null)
processor.EndSubmeshVertices(submesh);
}
VertexBufferReader.SkipExtraElements(reader, section);
}
/// <summary>
/// Reads a vertex element from a stream and sends it to an IVertexProcessor.
/// </summary>
/// <param name="reader">The stream to read from. It should be positioned at the start of the element.</param>
/// <param name="element">The layout of the element to read.</param>
/// <param name="boundingBox">The bounding box to transform the element with. Can be null.</param>
/// <param name="processor">The IVertexProcessor to send the element to.</param>
private static void ReadElement(IReader reader, VertexElementLayout element, IModelBoundingBox boundingBox, IVertexProcessor processor)
{
// EW EW EW
// TODO: Implement everything, this is just enough to load some Reach vertices for now...
float x = 0, y = 0, z = 0, w = 1;
uint value;
switch (element.Type)
{
case VertexElementType.Float2:
x = reader.ReadFloat();
y = reader.ReadFloat();
break;
case VertexElementType.Float3:
x = reader.ReadFloat();
y = reader.ReadFloat();
z = reader.ReadFloat();
break;
case VertexElementType.Float4:
x = reader.ReadFloat();
y = reader.ReadFloat();
z = reader.ReadFloat();
w = reader.ReadFloat();
break;
case VertexElementType.UByte4:
x = reader.ReadByte();
y = reader.ReadByte();
z = reader.ReadByte();
w = reader.ReadByte();
break;
case VertexElementType.UByte4N:
x = reader.ReadByte() / 255.0f;
y = reader.ReadByte() / 255.0f;
z = reader.ReadByte() / 255.0f;
w = reader.ReadByte() / 255.0f;
break;
case VertexElementType.Byte4N:
x = reader.ReadSByte() / 127.0f;
y = reader.ReadSByte() / 127.0f;
z = reader.ReadSByte() / 127.0f;
w = reader.ReadSByte() / 127.0f;
break;
case VertexElementType.Float16_2:
x = Half.ToHalf(reader.ReadUInt16());
y = Half.ToHalf(reader.ReadUInt16());
break;
case VertexElementType.Float16_4:
x = Half.ToHalf(reader.ReadUInt16());
y = Half.ToHalf(reader.ReadUInt16());
z = Half.ToHalf(reader.ReadUInt16());
w = Half.ToHalf(reader.ReadUInt16());
break;
case VertexElementType.UShort2:
x = reader.ReadUInt16();
y = reader.ReadUInt16();
break;
case VertexElementType.UShort2N:
x = reader.ReadUInt16() / 65535.0f;
y = reader.ReadUInt16() / 65535.0f;
break;
case VertexElementType.UShort4N:
x = reader.ReadUInt16() / 65535.0f;
y = reader.ReadUInt16() / 65535.0f;
z = reader.ReadUInt16() / 65535.0f;
w = reader.ReadUInt16() / 65535.0f;
break;
case VertexElementType.Short4N:
x = reader.ReadInt16() / 32767.0f;
y = reader.ReadInt16() / 32767.0f;
z = reader.ReadInt16() / 32767.0f;
w = reader.ReadInt16() / 32767.0f;
break;
case VertexElementType.D3DColor:
w = reader.ReadByte() / 255.0f; // W is set here because alpha comes first but ends up last in the vector
y = reader.ReadByte() / 255.0f;
z = reader.ReadByte() / 255.0f;
x = reader.ReadByte() / 255.0f;
break;
case VertexElementType.DHen3N:
value = reader.ReadUInt32();
x = (((int)((value << 21) & 0xFFE00000)) >> 21) / 1023.0f;
y = (((int)((value << 10) & 0xFFE00000)) >> 21) / 1023.0f;
z = (((int)(value & 0xFFC00000)) >> 22) / 511.0f;
break;
case VertexElementType.UDec4N:
value = reader.ReadUInt32();
x = (value & 0x3FF) / 1023.0f;
y = ((value >> 10) & 0x3FF) / 1023.0f;
z = ((value >> 20) & 0x3FF) / 1023.0f;
w = (value >> 30) / 3.0f;
break;
default:
throw new NotSupportedException("Unsupported vertex element type: " + Enum.GetName(typeof(VertexElementType), element.Type));
}
if (boundingBox != null)
TransformElement(ref x, ref y, ref z, ref w, element.Usage, boundingBox);
if (processor != null)
processor.ProcessVertexElement(x, y, z, w, element);
}
/// <summary>
/// Transforms a vertex element based upon a model's bounding box information.
/// </summary>
/// <param name="x">The X component of the element.</param>
/// <param name="y">The Y component of the element.</param>
/// <param name="z">The Z component of the element.</param>
/// <param name="w">The W component of the element.</param>
/// <param name="usage">The usage of the vertex element.</param>
/// <param name="boundingBox">The bounding box to transform the element by.</param>
private static void TransformElement(ref float x, ref float y, ref float z, ref float w, VertexElementUsage usage, IModelBoundingBox boundingBox)
{
switch (usage)
{
case VertexElementUsage.Position:
x = x * (boundingBox.MaxX - boundingBox.MinX) + boundingBox.MinX;
y = y * (boundingBox.MaxY - boundingBox.MinY) + boundingBox.MinY;
z = z * (boundingBox.MaxZ - boundingBox.MinZ) + boundingBox.MinZ;
break;
case VertexElementUsage.TexCoords:
x = x * (boundingBox.MaxU - boundingBox.MinU) + boundingBox.MinU;
y = y * (boundingBox.MaxV - boundingBox.MinV) + boundingBox.MinV;
break;
}
}
