private PixelInformation getIlluminationDirectionPerRenderingPixel(SpacecraftState sc, uint x, uint y)
{
PixelInformation PixelOut = new PixelInformation();
Vector3D c_pos = sc.getPosition();
// STEP 1: Visibility Test
Vector3D rayDirection = (sc.getPOVDirection() + (((1 + Convert.ToDouble(this._height) - (2 * Convert.ToDouble(y))) / (2 * Convert.ToDouble(this._height))) * sc.getPOVUp()) - (((1 + Convert.ToDouble(this._width) - (2 * Convert.ToDouble(x))) / (2 * Convert.ToDouble(this._width))) * sc.getPOVRight())).unit();
double discriminant = 4 * Math.Pow(c_pos * rayDirection, 2) - 4 * (rayDirection * rayDirection) * (c_pos * c_pos) + 4 * (rayDirection * rayDirection) * Math.Pow(_moon_radius, 2);
bool encounter = false;
Vector3D p_surf = new Vector3D();
if (discriminant < 0)
{
// no encounter
}
else if (discriminant == 0)
{
// one intersection
encounter = true;
double t = (-2 * (c_pos * rayDirection)) / (2 * (rayDirection * rayDirection));
p_surf = c_pos + rayDirection * t;
}
else
{
// two intersections
encounter = true;
double t1 = (-2 * (c_pos * rayDirection) + Math.Sqrt(discriminant)) / (2 * (rayDirection * rayDirection));
double t2 = (-2 * (c_pos * rayDirection) - Math.Sqrt(discriminant)) / (2 * (rayDirection * rayDirection));
Vector3D ray_point1 = c_pos + rayDirection * t1;
Vector3D ray_point2 = c_pos + rayDirection * t2;
double ray_norm1 = (ray_point1 - c_pos).norm();
double ray_norm2 = (ray_point2 - c_pos).norm();
if (ray_norm1 < ray_norm2)
{
p_surf = ray_point1;
}
else
{
p_surf = ray_point2;
}
}
if (encounter)
{
/*
Pixel shows the Moon's surface: Continue with executing steps 2 - 8.
*/
double x1 = Convert.ToDouble(x);
double y1 = Convert.ToDouble(y);
// STEP 2: Obtaining the Surface Hit Point
PixelOut.lat = tools.rad2deg((Math.PI / 2) - Math.Acos(p_surf.z() / _moon_radius));
PixelOut.lon = tools.rad2deg(Math.Atan2(p_surf.y(), p_surf.x()));
// STEP 3: Calculation of the Sun's direction
Vector3D hat_p_surf = p_surf.unit();
Vector3D hat_d_sun = (sc.getSunPosition() - p_surf).unit();
// STEP 4: Derivation of the Local Tangent Plane of the Surface Hit Point (nothing to do here)
// STEP 5: Determination of a Subsurface Point of the Solar Illumination Direction on the Local Tangent Plane
double lambda_5 = -(1000 * (hat_d_sun.x() * hat_p_surf.x() + hat_d_sun.y() * hat_p_surf.y() + hat_d_sun.z() * hat_p_surf.z())) / (hat_p_surf.x() * hat_p_surf.x() + hat_p_surf.y() * hat_p_surf.y() + hat_p_surf.z() * hat_p_surf.z());
Vector3D p_local = p_surf + 1000 * hat_d_sun + lambda_5 * hat_p_surf;
// STEP 6: Local Illumination Direction
Vector3D hat_d_local = (p_local - c_pos).unit();
/// STEP 7: Projection of the Local Illumination Point to the Image Plane
Vector3D k = c_pos + sc.getPOVDirection();
Vector3D c_up = sc.getPOVUp();
Vector3D c_right = sc.getPOVRight();
double w = Convert.ToDouble(this._width);
double h = Convert.ToDouble(this._height);
double x2 =
(
-2 * w * c_pos.y() * c_up.z() * hat_d_local.x() - c_right.y() * c_up.z() * hat_d_local.x() - w * c_right.y() * c_up.z() * hat_d_local.x()
+ 2 * w * c_pos.x() * c_up.z() * hat_d_local.y() + c_right.x() * c_up.z() * hat_d_local.y() + w * c_right.x() * c_up.z() * hat_d_local.y()
+ 2 * w * c_pos.z() * (c_up.y() * hat_d_local.x() - c_up.x() * hat_d_local.y())
+ (1 + w) * c_right.z() * (c_up.y() * hat_d_local.x() - c_up.x() * hat_d_local.y())
+ 2 * w * c_pos.y() * c_up.x() * hat_d_local.z() + c_right.y() * c_up.x() * hat_d_local.z() + w * c_right.y() * c_up.x() * hat_d_local.z()
- 2 * w * c_pos.x() * c_up.y() * hat_d_local.z() - c_right.x() * c_up.y() * hat_d_local.z() - w * c_right.x() * c_up.y() * hat_d_local.z()
- 2 * w * c_up.z() * hat_d_local.y() * k.x() + 2 * w * c_up.y() * hat_d_local.z() * k.x() + 2 * w * c_up.z() * hat_d_local.x() * k.y() - 2 * w * c_up.x() * hat_d_local.z() * k.y()
- 2 * w * c_up.y() * hat_d_local.x() * k.z() + 2 * w * c_up.x() * hat_d_local.y() * k.z()
)/(
2 * (c_right.z() * (c_up.y() * hat_d_local.x() - c_up.x() * hat_d_local.y()) + c_right.y() * (-c_up.z() * hat_d_local.x() + c_up.x() * hat_d_local.z()) + c_right.x() * (c_up.z() * hat_d_local.y() - c_up.y() * hat_d_local.z()))
);
double y2 =
(
-c_right.z() * c_up.y() * hat_d_local.x() - h * c_right.z() * c_up.y() * hat_d_local.x() + c_right.y() * c_up.z() * hat_d_local.x()
+ h * c_right.y() * c_up.z() * hat_d_local.x() - 2 * h * c_pos.x() * c_right.z() * hat_d_local.y() + c_right.z() * c_up.x() * hat_d_local.y()
+ h * c_right.z() * c_up.x() * hat_d_local.y() - c_right.x() * c_up.z() * hat_d_local.y() - h * c_right.x() * c_up.z() * hat_d_local.y()
+ c_pos.z() * (-2 * h * c_right.y() * hat_d_local.x() + 2 * h * c_right.x() * hat_d_local.y()) + 2 * h * c_pos.x() * c_right.y() * hat_d_local.z()
- c_right.y() * c_up.x() * hat_d_local.z() - h * c_right.y() * c_up.x() * hat_d_local.z() + c_right.x() * c_up.y() * hat_d_local.z()
+ h * c_right.x() * c_up.y() * hat_d_local.z() + 2 * h * c_pos.y() * (c_right.z() * hat_d_local.x() - c_right.x() * hat_d_local.z())
+ 2 * h * c_right.z() * hat_d_local.y() * k.x() - 2 * h * c_right.y() * hat_d_local.z() * k.x() - 2 * h * c_right.z() * hat_d_local.x() * k.y()
+ 2 * h * c_right.x() * hat_d_local.z() * k.y() + 2 * h * c_right.y() * hat_d_local.x() * k.z() - 2 * h * c_right.x() * hat_d_local.y() * k.z()
)/(
2 * (c_right.z() * (-c_up.y() * hat_d_local.x() + c_up.x() * hat_d_local.y()) + c_right.y() * (c_up.z() * hat_d_local.x() - c_up.x() * hat_d_local.z()) + c_right.x() * (-c_up.z() * hat_d_local.y() + c_up.y() * hat_d_local.z()))
);
// STEP 8: The Local Solar Illumination Angle
Vector2D v1 = new Vector2D(0, 1000);
Vector2D v2 = new Vector2D(x2-x1, y2-y1);
if (v2.x() > 0)
{
PixelOut.IlluminationAngle = tools.rad2deg(Math.Acos((v1 * v2) / (v1.norm() * v2.norm())));
}
else
{
PixelOut.IlluminationAngle = tools.rad2deg(2 * Math.PI - Math.Acos((v1 * v2) / (v1.norm() * v2.norm())));
}
PixelOut.exists = true;
return PixelOut;
}
else
{
// next grid sample point
return PixelOut;
}
}
private void generatePOVRayFile(SpacecraftState sc, string filename)
{
ArrayList filetext = new ArrayList();
Vector3D scPos = sc.getPosition();
Vector3D sunPos = sc.getSunPosition();
/* POV-Ray file */
/* ============ */
filetext.Add("#version 3.7;");
filetext.Add("");
filetext.Add("#declare Orange = rgb <1,0.5,0>;");
filetext.Add("#declare Red = rgb <1,0,0>;");
filetext.Add("#declare Yellow = rgb <1,1,0>;");
filetext.Add("#declare moon = texture");
filetext.Add(" {");
filetext.Add(" pigment { color rgb<0.8, 0.8, 0.8> }");
filetext.Add(" finish");
filetext.Add(" {");
filetext.Add(" ambient 0.0");
filetext.Add(" diffuse 0.8");
filetext.Add(" }");
filetext.Add(" }");
filetext.Add("");
filetext.Add("global_settings");
filetext.Add("{");
filetext.Add(" charset utf8");
filetext.Add(" assumed_gamma 1.0");
filetext.Add("}");
filetext.Add("");
filetext.Add("camera");
filetext.Add("{");
filetext.Add(" perspective");
filetext.Add(" location <" + scPos.x()/1000 + ", " + scPos.y()/1000 + ", " + scPos.z()/1000 + ">");
filetext.Add(" right <" + sc.getPOVRight().x().ToString("0.0000000") + ", " + sc.getPOVRight().y().ToString("0.0000000") + ", " + sc.getPOVRight().z().ToString("0.0000000") + ">");
filetext.Add(" up <" + sc.getPOVUp().x().ToString("0.0000000") + ", " + sc.getPOVUp().y().ToString("0.0000000") + ", " + sc.getPOVUp().z().ToString("0.0000000") + ">");
filetext.Add(" direction <" + sc.getPOVDirection().x().ToString("0.0000000") + ", " + sc.getPOVDirection().y().ToString("0.0000000") + ", " + sc.getPOVDirection().z().ToString("0.0000000") + ">");
filetext.Add("}");
filetext.Add("");
if (!Program.ignoreSun)
{
filetext.Add("light_source");
filetext.Add("{");
filetext.Add(" <" + sunPos.x() / 1000 + ", " + sunPos.y() / 1000 + ", " + sunPos.z() / 1000 + ">");
filetext.Add(" color rgb<1, 1, 1>");
filetext.Add(" looks_like");
filetext.Add(" {");
filetext.Add(" sphere");
filetext.Add(" {");
filetext.Add(" 0, 1000");
filetext.Add(" pigment { rgbt 1 }");
filetext.Add(" hollow");
filetext.Add(" interior");
filetext.Add(" {");
filetext.Add(" media");
filetext.Add(" {");
filetext.Add(" emission 1");
filetext.Add(" density");
filetext.Add(" {");
filetext.Add(" spherical");
filetext.Add(" density_map");
filetext.Add(" {");
filetext.Add(" [0 rgb 0]");
filetext.Add(" [60 Orange]");
filetext.Add(" [80 Red]");
filetext.Add(" [100 Yellow]");
filetext.Add(" }");
filetext.Add(" scale 1000");
filetext.Add(" }");
filetext.Add(" }");
filetext.Add(" }");
filetext.Add(" }");
filetext.Add(" }");
filetext.Add("}");
}
else
{
filetext.Add("light_source");
filetext.Add("{");
filetext.Add(" <" + scPos.x() / 1000 + ", " + scPos.y() / 1000 + ", " + scPos.z() / 1000 + ">");
filetext.Add(" color rgb<1, 1, 1>");
filetext.Add("}");
}
filetext.Add("");
// Dynamical Surface Pattern Selection Algorithm (DSPSA)
ArrayList pattern = new ArrayList();
for (double y = 1; y <= this._height; y++)
{
for (double x = 1; x <= this._width; x++)
{
Vector3D rayDirection = sc.getPOVDirection() + (((1 + this._height - (2 * y)) / (2 * this._height)) * sc.getPOVUp()) - (((1 + this._width - (2 * x)) / (2 * this._width)) * sc.getPOVRight());
this.DSPSA(rayDirection, scPos, pattern);
}
}
foreach (string str in pattern)
{
filetext.Add("#include \"" + this._pattern_repos + this._res + "\\pattern_LDEM_" + this._res + str + ".inc\"");
}
/* FOR DEBUG: diplay three dots as axis marker
filetext.Add("sphere { <1800,0,0>, 100 pigment { color rgb <1.0, 0.0, 0.0> } finish { ambient 1.0 diffuse 1.0 } no_shadow }");
filetext.Add("sphere { <0,1800,0>, 100 pigment { color rgb <1.0, 1.0, 0.0> } finish { ambient 1.0 diffuse 1.0 } no_shadow }");
filetext.Add("sphere { <0,0,1800>, 100 pigment { color rgb <0.0, 1.0, 0.0> } finish { ambient 1.0 diffuse 1.0 } no_shadow }");
*/
filetext.Add("");
filetext.Add("//-------------------------DEBUG INFORMATION-------------------------------------------------------------------------------------------------------");
filetext.Add("// MSISF Version: " + Program.VERSION);
filetext.Add("// Config:");
filetext.Add("// SimTime: " + sc.getTime().ToString(Program.scientificFormat));
filetext.Add("// s/c position: [" + scPos.x().ToString(Program.scientificFormat) + "," + scPos.y().ToString(Program.scientificFormat) + "," + scPos.z().ToString(Program.scientificFormat) + "]");
filetext.Add("// s/c orientation: [" + sc.getOrientation().v().x().ToString(Program.scientificFormat) + "," + sc.getOrientation().v().y().ToString(Program.scientificFormat) + "," + sc.getOrientation().v().z().ToString(Program.scientificFormat) + "," + sc.getOrientation().r().ToString(Program.scientificFormat) + "]");
filetext.Add("//-----------------------END DEBUG INFORMATION------------------------------------------------------------------------------------------------------");
TextWriter file = new System.IO.StreamWriter(filename + ".pov", false);
foreach (string line in filetext)
{
file.WriteLine(line);
}
file.Close();
string md5 = tools.md5File(filename + ".pov");
file = new System.IO.StreamWriter(filename + ".pov", true);
file.WriteLine("// " + md5);
file.Close();
/* META INFORMATION FILE (XML FILE) */
/* ================================ */
filetext = new ArrayList();
filetext.Add("<?xml version=\"1.0\" encoding=\"UTF-8\" standalone=\"no\"?>");
filetext.Add("<!DOCTYPE MSISRendering SYSTEM \"../lib/MSISRendering.dtd\">");
filetext.Add("<MSISRendering>");
// GENERAL INFORMATION
filetext.Add(" <GeneralInformation>");
filetext.Add(" <SimulationTime>");
filetext.Add(" <MJD>" + sc.getTime().ToString(Program.scientificFormat) + "</MJD>");
filetext.Add(" <UTC>" + tools.MJDtoUTC(sc.getTime()).ToString("s") + "Z</UTC>");
filetext.Add(" </SimulationTime>");
filetext.Add(" <CameraPosition unit=\"m\">");
filetext.Add(" <Vector3D x=\"" + sc.getPosition().x().ToString(Program.scientificFormat) + "\" y=\"" + sc.getPosition().y().ToString(Program.scientificFormat) + "\" z=\"" + sc.getPosition().z().ToString(Program.scientificFormat) + "\" />");
filetext.Add(" </CameraPosition>");
filetext.Add(" <CameraOrientation>");
filetext.Add(" <Quaternion r=\"" + sc.getOrientation().r().ToString(Program.scientificFormat) + "\" x=\"" + sc.getOrientation().v().x().ToString(Program.scientificFormat) + "\" y=\"" + sc.getOrientation().v().y().ToString(Program.scientificFormat) + "\" z=\"" + sc.getOrientation().v().z().ToString(Program.scientificFormat) + "\" />");
filetext.Add(" </CameraOrientation>");
filetext.Add(" <SunPosition unit=\"m\">");
filetext.Add(" <Vector3D x=\"" + sc.getSunPosition().x().ToString(Program.scientificFormat) + "\" y=\"" + sc.getSunPosition().y().ToString(Program.scientificFormat) + "\" z=\"" + sc.getSunPosition().z().ToString(Program.scientificFormat) + "\" />");
filetext.Add(" </SunPosition>");
filetext.Add(" <FlightAltitude unit=\"m\">" + (sc.getPosition().norm() - 1.73715E6).ToString(Program.scientificFormat) + "</FlightAltitude>");
filetext.Add(" <SurfaceResolution unit=\"px/deg\">" + this._res.ToString() + "</SurfaceResolution>");
filetext.Add(" <FOV unit=\"deg\">" + this._FOV.ToString() + "</FOV>");
filetext.Add(" <MSISVersion>" + Program.VERSION + "</MSISVersion>");
filetext.Add(" <CommandLine>" + Program.commandLineString +"</CommandLine>");
filetext.Add(" </GeneralInformation>");
// PIXEL INFORMATION
filetext.Add(" <PixelInformation>");
for(uint y = this.gridV; y <= this._height; y += this.gridV)
{
for(uint x = this.gridH; x <= this._width; x += this.gridH)
{
PixelInformation PixelMetaData = new PixelInformation();
// if getIlluminationDirectionPerRenderingPixel() returns false, the Moon's
// surface has not been hit (the respective pixel shows the space background)
PixelMetaData = getIlluminationDirectionPerRenderingPixel(sc, x, y);
if (PixelMetaData.exists)
{
filetext.Add(" <Pixel h=\"" + x.ToString() + "\" v=\"" + y.ToString() + "\">");
filetext.Add(" <SelenographicCoordinates lat=\"" + PixelMetaData.lat.ToString(Program.scientificFormat) + "\" lon=\"" + PixelMetaData.lon.ToString(Program.scientificFormat) + "\" units=\"deg\" />");
filetext.Add(" <IlluminationDirection unit=\"deg\">" + PixelMetaData.IlluminationAngle.ToString(Program.scientificFormat) + "</IlluminationDirection>");
filetext.Add(" </Pixel>");
sc.PixelInfo.Add(new Vector2D(Convert.ToDouble(x), Convert.ToDouble(y)), PixelMetaData);
}
}
}
filetext.Add(" </PixelInformation>");
filetext.Add("</MSISRendering>");
file = new System.IO.StreamWriter(filename + ".xml", false);
foreach (string line in filetext)
{
file.WriteLine(line);
}
file.Close();
}