void StarDatabase::findVisibleStars(StarHandler& starHandler,
const Point3f& position,
const Quatf& orientation,
float fovY,
float aspectRatio,
float limitingMag) const
{
// Compute the bounding planes of an infinite view frustum
Planef frustumPlanes[5];
Vec3f planeNormals[5];
Mat3f rot = orientation.toMatrix3();
float h = (float) tan(fovY / 2);
float w = h * aspectRatio;
planeNormals[0] = Vec3f(0, 1, -h);
planeNormals[1] = Vec3f(0, -1, -h);
planeNormals[2] = Vec3f(1, 0, -w);
planeNormals[3] = Vec3f(-1, 0, -w);
planeNormals[4] = Vec3f(0, 0, -1);
for (int i = 0; i < 5; i++)
{
planeNormals[i].normalize();
planeNormals[i] = planeNormals[i] * rot;
frustumPlanes[i] = Planef(planeNormals[i], position);
}
octreeRoot->processVisibleObjects(starHandler,
position,
frustumPlanes,
limitingMag,
STAR_OCTREE_ROOT_SIZE);
}
void Galaxy::renderGalaxyPointSprites(const GLContext&,
const Vec3f& offset,
const Quatf& viewerOrientation,
float brightness,
float pixelSize)
{
if (form == NULL)
return;
/* We'll first see if the galaxy's apparent size is big enough to
be noticeable on screen; if it's not we'll break right here,
avoiding all the overhead of the matrix transformations and
GL state changes: */
float distanceToDSO = offset.length() - getRadius();
if (distanceToDSO < 0)
distanceToDSO = 0;
float minimumFeatureSize = pixelSize * distanceToDSO;
float size = 2 * getRadius();
if (size < minimumFeatureSize)
return;
if (galaxyTex == NULL)
{
galaxyTex = CreateProceduralTexture(width, height, GL_RGBA,
GalaxyTextureEval);
}
assert(galaxyTex != NULL);
glEnable(GL_TEXTURE_2D);
galaxyTex->bind();
Mat3f viewMat = viewerOrientation.toMatrix3();
Vec3f v0 = Vec3f(-1, -1, 0) * viewMat;
Vec3f v1 = Vec3f( 1, -1, 0) * viewMat;
Vec3f v2 = Vec3f( 1, 1, 0) * viewMat;
Vec3f v3 = Vec3f(-1, 1, 0) * viewMat;
//Mat4f m = (getOrientation().toMatrix4() *
// Mat4f::scaling(form->scale) *
// Mat4f::scaling(getRadius()));
Mat3f m =
Mat3f::scaling(form->scale)*getOrientation().toMatrix3()*Mat3f::scaling(size);
// Note: fixed missing factor of 2 in getRadius() scaling of galaxy diameter!
// Note: fixed correct ordering of (non-commuting) operations!
int pow2 = 1;
vector<Blob>* points = form->blobs;
unsigned int nPoints = (unsigned int) (points->size() * clamp(getDetail()));
// corrections to avoid excessive brightening if viewed e.g. edge-on
float brightness_corr = 1.0f;
float cosi;
if (type < E0 || type > E3) //all galaxies, except ~round elliptics
{
cosi = Vec3f(0,1,0) * getOrientation().toMatrix3()
* offset/offset.length();
brightness_corr = (float) sqrt(abs(cosi));
if (brightness_corr < 0.2f)
brightness_corr = 0.2f;
}
if (type > E3) // only elliptics with higher ellipticities
{
cosi = Vec3f(1,0,0) * getOrientation().toMatrix3()
* offset/offset.length();
brightness_corr = brightness_corr * (float) abs((cosi));
if (brightness_corr < 0.45f)
brightness_corr = 0.45f;
}
glBegin(GL_QUADS);
for (unsigned int i = 0; i < nPoints; ++i)
{
if ((i & pow2) != 0)
{
pow2 <<= 1;
size /= 1.55f;
if (size < minimumFeatureSize)
break;
}
Blob b = (*points)[i];
Point3f p = b.position * m;
float br = b.brightness / 255.0f;
Color c = colorTable[b.colorIndex]; // lookup static color table
Point3f relPos = p + offset;
float screenFrac = size / relPos.distanceFromOrigin();
if (screenFrac < 0.1f)
{
float btot = ((type > SBc) && (type < Irr))? 2.5f: 5.0f;
float a = btot * (0.1f - screenFrac) * brightness_corr * brightness * br;
glColor4f(c.red(), c.green(), c.blue(), (4.0f*lightGain + 1.0f)*a);
glTexCoord2f(0, 0); glVertex(p + (v0 * size));
glTexCoord2f(1, 0); glVertex(p + (v1 * size));
glTexCoord2f(1, 1); glVertex(p + (v2 * size));
glTexCoord2f(0, 1); glVertex(p + (v3 * size));
}
}
glEnd();
}
