C++ (Cpp) Ptr::context Examples

Example #1

File: Geometry.cpp Project: 123woodman/minko

Geometry::Ptr
Geometry::computeTangentSpace(bool doNormals)
{
	const unsigned int numVertices = this->numVertices();

	if (numVertices == 0)
		return shared_from_this();

	if (!_data->hasProperty("position") 
		|| !_data->hasProperty("uv"))
		throw std::logic_error("Computation of tangent space requires positions and uv.");

	if (doNormals)
		computeNormals();

	const std::vector<unsigned short>& indices (this->indices()->data());
	const unsigned int numFaces = indices.size() / 3;

	unsigned short vertexIds[3] = { 0, 0, 0 };
	std::vector<Vector3::Ptr> xyz(3);
	std::vector<Vector2::Ptr> uv(3);

	VertexBuffer::Ptr xyzBuffer			= _data->get<VertexBuffer::Ptr>("position");
	const unsigned int xyzSize			= xyzBuffer->vertexSize();
	const unsigned int xyzOffset		= std::get<2>(*xyzBuffer->attribute("position"));
	const std::vector<float>& xyzData	= xyzBuffer->data();

	VertexBuffer::Ptr uvBuffer			= _data->get<VertexBuffer::Ptr>("uv");
	const unsigned int uvSize			= uvBuffer->vertexSize();
	const unsigned int uvOffset			= std::get<2>(*uvBuffer->attribute("uv"));
	const std::vector<float>& uvData	= uvBuffer->data();

	std::vector<float> tangentsData(3 * numVertices, 0.0f);

	for (unsigned int i = 0, offset = 0; i < numFaces; ++i)
	{
		for (unsigned int k = 0; k < 3; ++k)
		{
			vertexIds[k] = indices[offset++];
			unsigned int index = xyzOffset + vertexIds[k] * xyzSize;
			xyz[k] = Vector3::create(xyzData[index], xyzData[index + 1], xyzData[index + 2]);
			index = uvOffset + vertexIds[k] * uvSize;
			uv[k] = Vector2::create(uvData[index], uvData[index + 1]);
		}

		Vector2::Ptr uv02		= uv[0] - uv[2];
		Vector2::Ptr uv12		= uv[1] - uv[2];
		const float denom		= uv02->x() * uv12->y() - uv12->x() * uv02->y();
		const float invDenom	= fabsf(denom) > 1e-6f ? 1.0f/denom : 1.0f;

		Vector3::Ptr faceTangent = ((xyz[0]-xyz[2]) * uv12->y() - (xyz[1]-xyz[2]) * uv02->y()) * invDenom;

		for (unsigned int k=0; k<3; ++k)
		{
			const unsigned int index = 3 * vertexIds[k];

			tangentsData[index]		+= faceTangent->x();
			tangentsData[index + 1]	+= faceTangent->y();
			tangentsData[index + 2]	+= faceTangent->z();
		}
	}

	for (unsigned int i = 0, index = 0; i < numVertices; ++i, index += 3)
	{
		const float x				= tangentsData[index];
		const float y				= tangentsData[index + 1];
		const float z				= tangentsData[index + 2];
		const float lengthSquared	= x * x + y * y + z * z;
		const float invLength		= lengthSquared > 1e-6f ? 1.0f / sqrtf(lengthSquared) : 1.0f;

		tangentsData[index]		*= invLength;
		tangentsData[index + 1]	*= invLength;
		tangentsData[index + 2]	*= invLength;
	}

	VertexBuffer::Ptr tangentsBuffer = VertexBuffer::create(xyzBuffer->context(), tangentsData);
	tangentsBuffer->addAttribute("tangent", 3, 0);
	addVertexBuffer(tangentsBuffer);

	return shared_from_this();
}

Example #2

File: Geometry.cpp Project: 123woodman/minko

Geometry::Ptr
Geometry::computeNormals()
{
	const unsigned int numVertices = this->numVertices();

	if (numVertices == 0)
		return shared_from_this();

	if (_data->hasProperty("normal"))
		throw std::logic_error("The geometry already stores precomputed normals.");
		
	if (!_data->hasProperty("position"))
		throw std::logic_error("Computation of normals requires positions.");

	const std::vector<unsigned short>& indices	= this->indices()->data();
	const unsigned int numFaces					= indices.size() / 3;

	unsigned short vertexIds[3] = { 0, 0, 0 };
	std::vector<Vector3::Ptr> xyz(3);

	VertexBuffer::Ptr xyzBuffer			= _data->get<VertexBuffer::Ptr>("position");
	const unsigned int xyzSize			= xyzBuffer->vertexSize();
	const unsigned int xyzOffset		= std::get<2>(*xyzBuffer->attribute("position"));
	const std::vector<float>& xyzData	= xyzBuffer->data();

	std::vector<float> normalsData(3 * numVertices, 0.0f);

	for (unsigned int i = 0, offset = 0; i < numFaces; ++i)
	{
		for (unsigned int k = 0; k < 3; ++k)
		{
			vertexIds[k] = indices[offset++];
			const unsigned int index = xyzOffset + vertexIds[k] * xyzSize;
			xyz[k] = Vector3::create(xyzData[index], xyzData[index + 1], xyzData[index + 2]);
		}

		Vector3::Ptr faceNormal = Vector3::create()
			->copyFrom(xyz[0] - xyz[1])
			->cross(xyz[0] - xyz[2]);

 		for (unsigned int k = 0; k < 3; ++k)
		{
			const unsigned int index = 3 * vertexIds[k];

			normalsData[index]		+= faceNormal->x();
			normalsData[index + 1]	+= faceNormal->y();
			normalsData[index + 2]	+= faceNormal->z();
		}
	}

	for (unsigned int i = 0, index = 0; i < numVertices; ++i, index += 3)
	{
		const float x				= normalsData[index];
		const float y				= normalsData[index + 1];
		const float z				= normalsData[index + 2];
		const float lengthSquared	= x * x + y * y + z * z;
		const float invLength		= lengthSquared > 1e-6f ? 1.0f / sqrtf(lengthSquared) : 1.0f;

		normalsData[index]		*= invLength;
		normalsData[index + 1]	*= invLength;
		normalsData[index + 2]	*= invLength;
	}

	VertexBuffer::Ptr normalsBuffer = VertexBuffer::create(xyzBuffer->context(), normalsData);
	normalsBuffer->addAttribute("normal", 3, 0);
	addVertexBuffer(normalsBuffer);

	return shared_from_this();
}