void ExampleExperimentFields::DrawScalarField()
{
viewer->clear();
//Load scalar field
ScalarField2 field;
if (!field.load(ScalarfieldFilename))
{
output << "Error loading field file " << ScalarfieldFilename << "\n";
return;
}
//Get the minimum/maximum value in that field
float32 min = std::numeric_limits<float32>::max();
float32 max = -std::numeric_limits<float32>::max();
for(size_t j=0; j<field.dims()[1]; j++)
{
for(size_t i=0; i< field.dims()[0]; i++)
{
const float32 val = field.nodeScalar(i,j);
min = val < min ? val : min;
max = val > max ? val : max;
}
}
//Draw a point for each grid vertex.
for(size_t j=0; j<field.dims()[1]; j++)
{
for(size_t i=0; i<field.dims()[0]; i++)
{
const float32 val = field.nodeScalar(i, j);
const float32 c = (val - min) / (max - min);
Point2D p;
p.position = field.nodePosition(i, j);
p.size = 5;
//Use a grayscale depending on the actual value
p.color[0] = c; p.color[1] = c; p.color[2] = c;
viewer->addPoint(p);
}
}
viewer->refresh();
}
void Experiment3_1::DrawRegularMesh()
{
viewer->clear();
//Load scalar field
ScalarField2 field;
if (!field.load(scalar_filename))
{
output << "Error loading field file " << scalar_filename << "\n";
return;
}
//Get the minimum/maximum value in that field
float32 min = std::numeric_limits<float32>::max();
float32 max = -std::numeric_limits<float32>::max();
for(size_t j=0; j<field.dims()[1]; j++)
{
for(size_t i=0; i< field.dims()[0]; i++)
{
const float32 val = field.nodeScalar(i,j);
min = val < min ? val : min;
max = val > max ? val : max;
}
}
//Plot the grid
//Traverse one dimension first and then the other dimension
for(size_t j=0; j<field.dims()[1]; j++)
{
viewer->addLine(field.nodePosition(0,j), field.nodePosition(field.dims()[0]-1,j), makeVector4f(0.5,0.5,0.5,grid_alpha), 1);
}
for(size_t i=0; i<field.dims()[0]; i++)
{
viewer->addLine(field.nodePosition(i,0), field.nodePosition(i,field.dims()[1]-1), makeVector4f(0.5,0.5,0.5,grid_alpha), 1);
}
//Optionally overlay data on the grid
if (grid_w_data == true )
{
//Draw a point for each grid vertex.
for(size_t j=0; j<field.dims()[1]; j++)
{
for(size_t i=0; i<field.dims()[0]; i++)
{
const float32 val = field.nodeScalar(i, j);
const float32 c = (val - min) / (max - min);
Point2D p;
p.position = field.nodePosition(i, j);
p.size = 5;
//Use a grayscale depending on the actual value
p.color[0] = c; p.color[1] = c; p.color[2] = c;
viewer->addPoint(p);
}
}
}
viewer->refresh();
}
void Experiment3_1::DrawIsoContour_Asymp()
{
viewer->clear();
//Load scalar field
ScalarField2 field;
if (!field.load(scalar_filename))
{
output << "Error loading field file " << scalar_filename << "\n";
return;
}
//Get the minimum/maximum value in that field
float32 min = std::numeric_limits<float32>::max();
float32 max = -std::numeric_limits<float32>::max();
for(size_t j=0; j<field.dims()[1]; j++)
{
for(size_t i=0; i< field.dims()[0]; i++)
{
const float32 val = field.nodeScalar(i,j);
min = val < min ? val : min;
max = val > max ? val : max;
}
}
//Plot the grid
//Traverse one dimension first and then the other dimension
for(size_t j=0; j<field.dims()[1]; j++)
{
viewer->addLine(field.nodePosition(0,j), field.nodePosition(field.dims()[0]-1,j), makeVector4f(0.5,0.5,0.5,grid_alpha), 1);
}
for(size_t i=0; i<field.dims()[0]; i++)
{
viewer->addLine(field.nodePosition(i,0), field.nodePosition(i,field.dims()[1]-1), makeVector4f(0.5,0.5,0.5,grid_alpha), 1);
}
//Optionally overlay data on the grid
if (grid_w_data == true )
{
//Draw a point for each grid vertex.
for(size_t j=0; j<field.dims()[1]; j++)
{
for(size_t i=0; i<field.dims()[0]; i++)
{
const float32 val = field.nodeScalar(i, j);
const float32 c = (val - min) / (max - min);
Point2D p;
p.position = field.nodePosition(i, j);
p.size = 5;
//Use a grayscale depending on the actual value
p.color[0] = c; p.color[1] = c; p.color[2] = c;
viewer->addPoint(p);
}
}
}
viewer->refresh();
//Plot the Iso Contour
//Traverse the cells
for(size_t i=0; i<field.dims()[0]-1; i++)
{
for(size_t j=0; j<field.dims()[1]-1; j++)
{
//Compute Max and Min values in each cell
float32 fval[4];
fval[0]= field.nodeScalar(i,j);
fval[1]= field.nodeScalar(i,j+1);
fval[2]= field.nodeScalar(i+1,j+1);
fval[3]= field.nodeScalar(i+1,j);
vector <Vector2f> Pos;
Pos.resize(4);
Pos[0]=field.nodePosition(i,j);
Pos[1]=field.nodePosition(i,j+1);
Pos[2]=field.nodePosition(i+1,j+1);
Pos[3]=field.nodePosition(i+1,j);
//output << "** "<< Pos[0][0] << " " << Pos[0][1] <<"\n";
//output << field.nodePosition(i,j)[0] << " "<< field.nodePosition(i,j)[1] << "\n" ;
float32 maxf, minf;
maxf=fmax(fval[0],fval[1]);
maxf=fmax(maxf,fval[2]);
maxf=fmax(maxf,fval[3]);
minf=fmin(fval[0],fval[1]);
minf=fmin(minf,fval[2]);
minf=fmin(minf,fval[3]);
//Check if the iso contour passes the grid
if((iso_c < minf) || (iso_c > maxf))
continue;
else //We plot the iso contour
{
float32 EdgeChar[3][4];
//Now figure out the signs for the four nodes
bool sign[4]= {0,0,0,0};
for(int k=0; k<4; k++)
{
if(fval[k]>=iso_c)
sign[k] = 1;
}
//Traverse the nodes clockwise and see if the edge carries a crossing point
for(int k=0; k<4; k++)
{
if( sign[k] ^ sign[(k+1)%4] )
{
EdgeChar[2][k] = 1;
float32 x,y;
x = ( (Pos[(k+1)%4][0] - Pos[k][0])*iso_c + Pos[k][0] * fval[(k+1)%4] - Pos[(k+1)%4][0] * fval[k] ) / ( fval[(k+1)%4] - fval[k] ) ;
y = ( (Pos[(k+1)%4][1] - Pos[k][1])*iso_c + Pos[k][1] * fval[(k+1)%4] - Pos[(k+1)%4][1] * fval[k] ) / ( fval[(k+1)%4] - fval[k] ) ;
EdgeChar[0][k] = x;
EdgeChar[1][k] = y;
}
else
EdgeChar[2][k] = 0;
}
//Count the number of edges that have a valid crossing point. It should be either 2 or 4
int EdgeCount=0;
for(int k=0; k<4; k++)
{
if(EdgeChar[2][k]==1)
EdgeCount++;
}
if(EdgeCount == 2)
{
//Simply plot the contour
vector <Vector2f> LineEnd;
LineEnd.clear();
LineEnd.resize(2);
int index=0;
for(int k=0; k<4; k++)
{
if(EdgeChar[2][k]==1)
{
LineEnd[index]= makeVector2f(EdgeChar[0][k], EdgeChar[1][k]) ;
index++;
}
}
viewer->addLine(LineEnd[0], LineEnd[1], makeVector4f(0.5,0.5,0.5,iso_alpha), 2);
viewer->refresh();
}
else //Cell has the contour intersecting at 4 points
{
//There is an ambiguity to be resolved
float32 fmid= (fval[3]*fval[1] - fval[2]*fval[0]) / ( fval[3]+fval[1] -fval[2] - fval[0] ) ;
vector <Vector2f> LineEnd;
LineEnd.clear();
LineEnd.resize(4);
for(int k=0; k<4; k++)
{
LineEnd[k]= makeVector2f(EdgeChar[0][k], EdgeChar[1][k]) ;
}
if(fval[1] < iso_c)
{
if(iso_c > fmid) //Connect 3 to 0 and 1 to 2
{
viewer->addLine(LineEnd[3], LineEnd[0], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->addLine(LineEnd[1], LineEnd[2], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->refresh();
}
else //Connect 0 to 1 and 2 to 3
{
viewer->addLine(LineEnd[0], LineEnd[1], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->addLine(LineEnd[2], LineEnd[3], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->refresh();
}
}
else
{
if(iso_c > fmid) //Connect 0 to 1 and 2 to 3
{
viewer->addLine(LineEnd[0], LineEnd[1], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->addLine(LineEnd[2], LineEnd[3], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->refresh();
}
else //Connect 3 to 0 and 1 to 2
{
viewer->addLine(LineEnd[3], LineEnd[0], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->addLine(LineEnd[1], LineEnd[2], makeVector4f(1,0.5,0.5,iso_alpha), 2);
viewer->refresh();
}
}
}
}
}
}
}