QT3D how to render stl file

[jimfar]

Qt3DRender::QGeometry *geometry = new Qt3DRender::QGeometry;

Qt3DRender::QAttribute *m_positionAttr = new Qt3DRender::QAttribute(geometry);
 Qt3DRender::QAttribute *m_NORAttr = new Qt3DRender::QAttribute(geometry);

Qt3DRender::QBuffer *m_positionBuffer = new Qt3DRender::QBuffer(Qt3DRender::QBuffer::VertexBuffer, geometry);
 
Qt3DRender::QBuffer *m_NORBuffer = new Qt3DRender::QBuffer(Qt3DRender::QBuffer::VertexBuffer, geometry);

int vsize = p3dparser->mmeshs[0].mVertices.size();
int isize = p3dparser->mmeshs[0].mIndices.size();
//Configure the attributes access
QByteArray colorData;
int size1 = sizeof(QVector3D);
//positionData.resize(vsize * 3 * sizeof(float));
QByteArray mNormals;
char*pdata = (char*)&p3dparser->mmeshs[0].mVertices[0][0];
 

const int nVerts = vsize;
const int size = nVerts * 3 * sizeof(float);
QByteArray positionBytes,noramlbytes;
positionBytes.resize(size);
colorData.resize(size);
vsize = nVerts;
memcpy(positionBytes.data(), pdata, size);
m_positionBuffer->setData(positionBytes);


uint facenum = vsize /3;
uint j = 0, i = 0;
mNormals.resize(vsize*2*sizeof(Vector3));
Vector3*vertex = &p3dparser->mmeshs[0].mVertices[0];
Vector3*pnormal = (Vector3*)mNormals.data();
Vector3 n;
uint cnt = 0;
for ( j = 0; j <vsize*2; )
{
	if (j % 6 == 0) {
		n = CalcNormal(&vertex[cnt]);
		//n=Normalize(Cross(vertex[i] - vertex[i + 1], vertex[i+2] - vertex[i + 1]));
	}
	 
	pnormal[j++] = vertex[cnt++];
	pnormal[j++] = n;
	
	
}
 


m_NORBuffer->setData(mNormals);
const quint32 elementSize = 3 + 3  ;
const quint32 stride = elementSize * sizeof(float);
m_colorBuffer->setData(colorData);
m_positionAttr->setName(Qt3DRender::QAttribute::defaultPositionAttributeName());
m_positionAttr->setVertexBaseType(Qt3DRender::QAttribute::Float);
m_positionAttr->setDataSize(3);
m_positionAttr->setAttributeType(Qt3DRender::QAttribute::VertexAttribute);
m_positionAttr->setBuffer(m_NORBuffer);
m_positionAttr->setCount(vsize);
m_positionAttr->setByteStride(stride);
//m_positionAttr->setProperty();

m_NORAttr->setName(Qt3DRender::QAttribute::defaultNormalAttributeName());
m_NORAttr->setVertexBaseType(Qt3DRender::QAttribute::Float);
m_NORAttr->setDataSize(3);
m_NORAttr->setAttributeType(Qt3DRender::QAttribute::VertexAttribute);
m_NORAttr->setBuffer(m_NORBuffer);
m_NORAttr->setCount(vsize);
m_NORAttr->setByteOffset( 3 * sizeof(Vector3));
m_NORAttr->setByteStride(stride);

geometry->addAttribute(m_positionAttr);
// geometry->addAttribute(m_colorAttr);
geometry->addAttribute(m_NORAttr);
this is snipet for render stl file,it can display object but it is all black cant see the outline ,it seems the normal is wrong,can anyone help me ?

[jimfar]

i cant use mesh->setsource("***.stl") for some reason ,,,i want to render custom mesh by vertics it can be composed a set of triangle

[A Former User]

@jimfar said in QT3D how to render stl file:

i cant use mesh->setsource("***.stl") for some reason

Hi! What's the type of mesh?

[jimfar]

the mesh is the same with stl ,3 vertices and 1 normal .. yep i already fix it .3 * sizeof(Vector3))--->modify as 3 * sizeof(float)); it is my careless..thanks ur attention