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add comet tail vanishing code, distance sorted label display

ver1_5_1
Fridger Schrempp 2005-12-11 15:34:35 +00:00
parent 56c6bb71a6
commit 0493b69176
2 changed files with 80 additions and 48 deletions
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124
src/celengine/render.cpp
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@ -50,13 +50,11 @@ using namespace std;
#define GL_COLOR_SUM_EXT 0x8458
#endif
static const float STAR_DISTANCE_LIMIT = 1.0e6f;
static const double DSO_DISTANCE_LIMIT = 1.0e9;
static const int REF_DISTANCE_TO_SCREEN = 400; //[mm]
static const float LABELLED_STAR_DISTANCE_LIMIT = 5.0e4f;
static const double LABELLED_DSO_DISTANCE_LIMIT = 5.0e6;
static const float X0_SOL = astro::AUtoKilometers(5.0f);
static const int StarVertexListSize = 1024;
@ -136,6 +134,7 @@ Renderer::Renderer() :
windowWidth(0),
windowHeight(0),
fov(FOV),
screenDpi(96),
corrFac(1.12f),
faintestAutoMag45deg(7.0f),
renderMode(GL_FILL),
@ -155,9 +154,9 @@ Renderer::Renderer() :
usePointSprite(false),
textureResolution(medres),
minOrbitSize(MinOrbitSizeForLabel),
distanceLimit(1.0e6f),
minFeatureSize(MinFeatureSizeForLabel),
locationFilter(~0),
distanceLimit(1.0e6f),
colorTemp(NULL)
{
starVertexBuffer = new StarVertexBuffer(2048);
@ -586,6 +585,16 @@ void Renderer::setFieldOfView(float _fov)
corrFac = (0.12f * fov/FOV * fov/FOV + 1.0f);
}
int Renderer::getScreenDpi() const
{
return screenDpi;
}
void Renderer::setScreenDpi(int _dpi)
{
screenDpi = _dpi;
}
void Renderer::setFaintestAM45deg(float _faintestAutoMag45deg)
{
faintestAutoMag45deg = _faintestAutoMag45deg;
@ -710,7 +719,6 @@ float Renderer::getMinimumOrbitSize() const
return minOrbitSize;
}
// Orbits and labels are only rendered when the orbit of the object
// occupies some minimum number of pixels on screen.
void Renderer::setMinimumOrbitSize(float pixels)
@ -1248,7 +1256,6 @@ void Renderer::render(const Observer& observer,
// Compute the size of a pixel
setFieldOfView(radToDeg(observer.getFOV()));
pixelSize = calcPixelSize(fov, (float) windowHeight);
// Set up the projection we'll use for rendering stars.
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
@ -1787,6 +1794,7 @@ void Renderer::render(const Observer& observer,
renderList[i].appMag,
now,
observer.getOrientation(),
lightSourceLists[renderList[i].solarSysIndex],
nearPlaneDistance, farPlaneDistance);
}
else
@ -5781,10 +5789,15 @@ struct CometTailVertex
static CometTailVertex cometTailVertices[CometTailSlices * MaxCometTailPoints];
static void ProcessCometTailVertex(const CometTailVertex& v,
const Vec3f& viewDir)
const Vec3f& viewDir,
float fadeDistFromSun)
{
float shade = abs(viewDir * v.normal * v.brightness);
glColor4f(0.0f, 0.5f, 1.0f, shade);
// If fadeDistFromSun = x/x0 >= 1.0, comet tail starts fading,
// i.e. fadeFactor quickly transits from 1 to 0.
float fadeFactor = 0.5f - 0.5f * tanh(fadeDistFromSun - 1.0f / fadeDistFromSun);
float shade = abs(viewDir * v.normal * v.brightness * fadeFactor);
glColor4f(0.5f, 0.5f, 0.75f, shade);
glVertex(v.point);
}
@ -5853,6 +5866,7 @@ void Renderer::renderCometTail(const Body& body,
float appMag,
double now,
Quatf orientation,
const vector<LightSource>& lightSources,
float nearPlaneDistance,
float farPlaneDistance)
{
@ -5864,8 +5878,34 @@ void Renderer::renderCometTail(const Body& body,
float f = 1.0e15f;
int nSteps = MaxCometTailPoints;
float dt = 10000000.0f / (nSteps * (float) vd.length() * 100.0f);
// float dt = 0.1f;
float distanceFromSun, irradiance_max = 0.0f;
unsigned int li_eff;
// Find the sun with the largest irrradiance of light onto the comet
// as function of the comet's position;
// irradiance = sun's luminosity / square(distanceFromSun);
for (unsigned int li = 0; li < lightSources.size(); li++)
{
distanceFromSun = (body.getHeliocentricPosition(now) -
lightSources[li].position).length();
float irradiance = lightSources[li].luminosity / square(distanceFromSun);
if (irradiance > irradiance_max )
{
li_eff = li;
irradiance_max = irradiance;
}
}
float fadeDistance = 1.0f / (X0_SOL * sqrt(irradiance_max));
// direction to sun with dominant light irradiance:
Vec3d sd = body.getHeliocentricPosition(now) - lightSources[li_eff].position;
Vec3f sunDir = Vec3f((float) sd.x, (float) sd.y, (float) sd.z);
sunDir.normalize();
// cout<<astro::kilometersToAU(X0_SOL*sqrt(lightSources[li_eff].luminosity))<<" "<<fadeDistance<<" "<<astro::kilometersToAU(sd.length())<<endl;
int i;
#if 0
for (i = 0; i < MaxCometTailPoints; i++)
@ -5886,30 +5926,18 @@ void Renderer::renderCometTail(const Body& body,
}
#endif
// Compute a rough estimate of the visible length of the dust tail
float dustTailLength = (1.0e8f / (float) pos0.distanceFromOrigin()) *
(body.getRadius() / 5.0f) * 1.0e7f;
float dustTailRadius = dustTailLength * 0.1f;
float comaRadius = dustTailRadius * 0.5f;
Point3f origin(0, 0, 0);
{
Point3d pd = body.getOrbit()->positionAtTime(t);
Point3f p = Point3f((float) pd.x, (float) pd.y, (float) pd.z);
Vec3f sunDir = p - Point3f(0, 0, 0);
sunDir.normalize();
origin -= sunDir * (body.getRadius() * 100);
}
origin -= sunDir * (body.getRadius() * 100);
for (i = 0; i < MaxCometTailPoints; i++)
{
float alpha = (float) i / (float) MaxCometTailPoints;
alpha = alpha * alpha;
Point3d pd = body.getOrbit()->positionAtTime(t);
Point3f p = Point3f((float) pd.x, (float) pd.y, (float) pd.z);
Vec3f sunDir = p - Point3f(0, 0, 0);
sunDir.normalize();
cometPoints[i] = origin + sunDir * (dustTailLength * alpha);
}
@ -6018,13 +6046,13 @@ void Renderer::renderCometTail(const Body& body,
int n = i * CometTailSlices;
for (int j = 0; j < CometTailSlices; j++)
{
ProcessCometTailVertex(cometTailVertices[n + j], viewDir);
ProcessCometTailVertex(cometTailVertices[n + j], viewDir, fadeDistance);
ProcessCometTailVertex(cometTailVertices[n + j + CometTailSlices],
viewDir);
viewDir, fadeDistance);
}
ProcessCometTailVertex(cometTailVertices[n], viewDir);
ProcessCometTailVertex(cometTailVertices[n], viewDir, fadeDistance);
ProcessCometTailVertex(cometTailVertices[n + CometTailSlices],
viewDir);
viewDir, fadeDistance);
glEnd();
}
glEnable(GL_CULL_FACE);
@ -6538,16 +6566,16 @@ void DSORenderer::process(DeepSkyObject* const & dso,
// the parameters in the 'close' correction are fixed by matching
// the gradients at 10 pc and requiring brightness = r + ri at distanceToDSO = 0
double ri = 0.25, pc10 = 32.6167;
double r = absMag/avgAbsMag;
double num = 5*(absMag - faintestMag);
double a = r*(avgAbsMag - 5*faintestMag)/num;
double b = (1.0 - 5*r)/num;
double c = 0.4605170186*ri/b-1.0;
double close = ri*(pc10 - distanceToDSO)/(pc10 + distanceToDSO*c);
double brightness = (distanceToDSO >= pc10) ?
double ri = -0.1, pc10 = 32.6167;
double r = absMag / avgAbsMag;
double num = 5 * (absMag - faintestMag);
double a = r * (avgAbsMag - 5 * faintestMag) / num;
double b = (1.0 - 5 * r) / num;
double c = 0.4605170186 * ri / b - 1.0;
double close = ri * (pc10 - distanceToDSO) / (pc10 + distanceToDSO * c);
double brightness = (distanceToDSO >= pc10)?
a - b * astro::absToAppMag(absMag, (float) distanceToDSO): r + close;
brightness = 1.5*brightness*(faintestMag-3.0)/renderer->getFaintestAM45deg();
brightness = 1.5 * brightness * (faintestMag - 3.0)/renderer->getFaintestAM45deg();
if (brightness < 0.0)
brightness = 0.0;
@ -6557,9 +6585,9 @@ void DSORenderer::process(DeepSkyObject* const & dso,
// handling. We don't want to always set the projection
// matrix, since that could be expensive with large galaxy
// catalogs.
float nearZ = (float) distanceToDSO;
float farZ = (float) (relPos.length() + dsoRadius * 2);
if (nearZ < dsoRadius * 0.001f)
float nearZ = (float) (distanceToDSO/2);
float farZ = (float) (distanceToDSO + dsoRadius * 2);
if (nearZ < dsoRadius * 0.001)
{
nearZ = (float) (dsoRadius * 0.001);
farZ = nearZ * 10000.0f;
@ -6596,11 +6624,14 @@ void DSORenderer::process(DeepSkyObject* const & dso,
} // frustum test
} // renderFlags check
// avoid label overlap by FOV/fov-weighted distance cut-off!
// only render those labels that are in front of the camera:
// avoid label overlap by pixelSize-controlled apparent magnitude cut-off!
// Use pixelSize * screenDpi instead of FoV, to eliminate windowHeight dependence.
// Label appearance is sorted according to apparent galaxy brightness!
// Only render those labels that are in front of the camera:
float relDistanceToScreen = REF_DISTANCE_TO_SCREEN * pixelSize * renderer->getScreenDpi() / 25.4f; // = 1.0 initially, after startup
if ((dso->getLabelMask() & labelMode) &&
distanceToDSO < LABELLED_DSO_DISTANCE_LIMIT * FOV/fov &&
dot(relPos, viewNormal) > 0)
astro::absToAppMag(absMag, (float) distanceToDSO) < faintestMag * log10(5.0f/relDistanceToScreen) && dot(relPos, viewNormal) > 0)
{
renderer->addLabel(dsoDB->getDSOName(dso),
Color(0.1f, 0.85f, 0.85f, 1.0f),
@ -6626,7 +6657,6 @@ void Renderer::renderDeepSkyObjects(const Universe& universe,
dsoRenderer.renderer = this;
dsoRenderer.dsoDB = dsoDB;
dsoRenderer.orientationMatrix = conjugate(observer.getOrientation()).toMatrix3();
dsoRenderer.observer = &observer;
dsoRenderer.obsPos = obsPos;
dsoRenderer.viewNormal = Vec3f(0, 0, -1) * observer.getOrientation().toMatrix3();
@ -6636,14 +6666,12 @@ void Renderer::renderDeepSkyObjects(const Universe& universe,
dsoRenderer.pixelSize = pixelSize;
dsoRenderer.brightnessScale = brightnessScale * corrFac;
dsoRenderer.brightnessBias = brightnessBias;
dsoRenderer.avgAbsMag = dsoDB->getAverageAbsoluteMagnitude();
dsoRenderer.faintestMag = faintestMag;
dsoRenderer.faintestMagNight = faintestMagNight;
dsoRenderer.saturationMag = saturationMag;
dsoRenderer.renderFlags = renderFlags;
dsoRenderer.labelMode = labelMode;
//cout<<"dsoRenderer: "<<faintestMag<<" "<<saturationMag<<endl;
dsoRenderer.wWidth = windowWidth;
dsoRenderer.wHeight = windowHeight;

4
src/celengine/render.h
View File

@ -136,6 +136,8 @@ class Renderer
void setDistanceLimit(float);
int getOrbitMask() const;
void setOrbitMask(int);
int getScreenDpi() const;
void setScreenDpi(int);
const ColorTemperatureTable* getStarColorTable() const;
void setStarColorTable(const ColorTemperatureTable*);
@ -358,6 +360,7 @@ class Renderer
float appMag,
double now,
Quatf orientation,
const vector<LightSource>& lightSources,
float, float);
void renderBodyAsParticle(Point3f center,
@ -421,6 +424,7 @@ class Renderer
int windowWidth;
int windowHeight;
float fov;
int screenDpi;
float corrFac;
float pixelSize;
float faintestAutoMag45deg;