} // EvaluationOnDragginTheLine(...)
static bool IsPointOnLine(CheetahPoint2D point, CheetahLine2D line)
{
var k = (line.End.Y - line.Start.Y) / (line.End.X - line.Start.X);
var b = (line.Start.Y * line.End.X - line.End.Y * line.Start.X) / (line.End.X - line.Start.X);
var y = k * point.X + b;
return(Math.Abs(y - point.Y) < CheetahParametricBasic.Settings.Precision);
} // IsPointOnLine(...)
} // EvaluationOnDragginTheLine(...)
static bool IsPointOnLine(CheetahPoint2D point, CheetahLine2D line)
{
var k = (line.End.Y - line.Start.Y) / (line.End.X - line.Start.X);
var b = (line.Start.Y * line.End.X - line.End.Y * line.Start.X) / (line.End.X - line.Start.X);
var y = k * point.X + b;
return Math.Abs(y - point.Y) < CheetahParametricBasic.Settings.Precision;
} // IsPointOnLine(...)
} // EvaluationOnTheFirstApplicationOfConstraint(...)
static ICollection<CheetahCurve> EvaluationOnDragginTheLine(ICheetahSolver solver, CheetahDataSet dataSet,
CheetahLine2D draggingLine, CheetahPoint2D draggingPoint)
{
// 1. Creating parametric object and setting tolerance (by default 1E-12)
var parametric = new CheetahParametricBasic(() => solver, false, true, true);
// 2. Initializing parametric object using data set
// On this step we are compiling the model and creating system of equation
// After that we will be ready to run the solver
// We will drag the line, so we need to specify the curve to drag and the dragging point
if (!parametric.Init(dataSet, new[] { draggingLine }, new[] { draggingPoint }))
// If parametric.Init will return FALSE, then there is critical error in data set
// So we are not able to make system of equation and to evaluate the problem
// We should cancel the procedure and rebuild data set
throw new Exception("Something goes wrong");
// 3. Now we can drag. We don't need to recompile the model on each drag iteration,
// because the model will be the same - only initial value (the drag point) will be changed
// We are simulating drag using this loop
for (var i = 0; i < 100; i++)
{
// 4. Our parametric object is initialized by dataSet object
// So the current values of the dataSet curves are the initial values of the system
// If we will change some value - the initial values will be changed appropriately
// All that we need to reinitialize the model by the new point from the screen
// is to reset the value for the dragging line end point
draggingLine.End.X *= 1.01;
draggingLine.End.Y *= 1.05;
// 5. Regenerating constrained model (running solver)
// On this step we are solving the system of equation, that we've prepared on the previous step
// Now we are dragging the curve and, because we do it manually (by mouse), we can not be precise
// We don't need to calculate on each step with 10^-12 or greater precision
// So we can cheat a little and decrease the precision for drag iterations
// That's why we are using parametric.EvaluateFast function
if (!parametric.EvaluateFast())
// If parametric.EvaluateFast will return FALSE it usually means that we can not evaluate the system
// with this initial values (we have reached maximum number of iterations)/
// It is NOT a critical problem. This situation can appear while we drag some curve
// in position that conflict with constraints/
// For example, while we rounding out the arc and can get negative radius,
// or squeeze the line to zero length (and get negative length)
// In our solver, if we have such a situation - we restore the previous drag iteration solution.
throw new Exception("Something goes wrong");
// In this example we don't use results of EvaluateFast/
// In real life they may be retreived and used to update dragging lines on the screen
}
// 6. Regenerating constrained model (running solver)
// Now we "click the mouse button" to end the drag.
// We need to evaluate the system with high precision (that's why we use Evaluate instead of EvaluateFast)
// We can use last iteration solution as new initial value to evaluate the system much faster
// (for this purpose we set recompile parameter to false)
if (!parametric.Evaluate(false))
throw new Exception("Something goes wrong");
// 7. Retrieving results
var resultGeometry = parametric.GetSolution(true);
// 8. We have to clear compiled data
parametric.ClearSolver();
return resultGeometry;
} // EvaluationOnDragginTheLine(...)
} // EvaluationOnTheFirstApplicationOfConstraint(...)
static ICollection <CheetahCurve> EvaluationOnDragginTheLine(ICheetahSolver solver, CheetahDataSet dataSet,
CheetahLine2D draggingLine, CheetahPoint2D draggingPoint)
{
// 1. Creating parametric object and setting tolerance (by default 1E-12)
var parametric = new CheetahParametricBasic(() => solver, false, true, true);
// 2. Initializing parametric object using data set
// On this step we are compiling the model and creating system of equation
// After that we will be ready to run the solver
// We will drag the line, so we need to specify the curve to drag and the dragging point
if (!parametric.Init(dataSet, new[] { draggingLine }, new[] { draggingPoint }))
{
// If parametric.Init will return FALSE, then there is critical error in data set
// So we are not able to make system of equation and to evaluate the problem
// We should cancel the procedure and rebuild data set
throw new Exception("Something goes wrong");
}
// 3. Now we can drag. We don't need to recompile the model on each drag iteration,
// because the model will be the same - only initial value (the drag point) will be changed
// We are simulating drag using this loop
for (var i = 0; i < 100; i++)
{
// 4. Our parametric object is initialized by dataSet object
// So the current values of the dataSet curves are the initial values of the system
// If we will change some value - the initial values will be changed appropriately
// All that we need to reinitialize the model by the new point from the screen
// is to reset the value for the dragging line end point
draggingLine.End.X *= 1.01;
draggingLine.End.Y *= 1.05;
// 5. Regenerating constrained model (running solver)
// On this step we are solving the system of equation, that we've prepared on the previous step
// Now we are dragging the curve and, because we do it manually (by mouse), we can not be precise
// We don't need to calculate on each step with 10^-12 or greater precision
// So we can cheat a little and decrease the precision for drag iterations
// That's why we are using parametric.EvaluateFast function
if (!parametric.EvaluateFast())
{
// If parametric.EvaluateFast will return FALSE it usually means that we can not evaluate the system
// with this initial values (we have reached maximum number of iterations)/
// It is NOT a critical problem. This situation can appear while we drag some curve
// in position that conflict with constraints/
// For example, while we rounding out the arc and can get negative radius,
// or squeeze the line to zero length (and get negative length)
// In our solver, if we have such a situation - we restore the previous drag iteration solution.
throw new Exception("Something goes wrong");
}
// In this example we don't use results of EvaluateFast/
// In real life they may be retreived and used to update dragging lines on the screen
}
// 6. Regenerating constrained model (running solver)
// Now we "click the mouse button" to end the drag.
// We need to evaluate the system with high precision (that's why we use Evaluate instead of EvaluateFast)
// We can use last iteration solution as new initial value to evaluate the system much faster
// (for this purpose we set recompile parameter to false)
if (!parametric.Evaluate(false))
{
throw new Exception("Something goes wrong");
}
// 7. Retrieving results
var resultGeometry = parametric.GetSolution(true);
// 8. We have to clear compiled data
parametric.ClearSolver();
return(resultGeometry);
} // EvaluationOnDragginTheLine(...)
