Droog71/oolite
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Switched lighting calculations to single precision, there is no clear need for double-precision trancendentals here.

Browse Source 
git-svn-id: http://svn.berlios.de/svnroot/repos/oolite-linux/trunk@5055 127b21dd-08f5-0310-b4b7-95ae10353056
This commit is contained in:
Jens Ayton 2012-07-08 20:05:15 +00:00
parent 1dce047d0f
commit 8983fbf3e1
1 changed files with 42 additions and 39 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

81
src/Core/CollisionRegion.m
View File

@ -451,17 +451,16 @@ static NSArray *subregionsContainingPosition(Vector position, CollisionRegion *r
// an outValue of 1 means it's just being occluded.
static BOOL entityByEntityOcclusionToValue(Entity *e1, Entity *e2, OOSunEntity *the_sun, double *outValue)
static BOOL entityByEntityOcclusionToValue(Entity *e1, Entity *e2, OOSunEntity *the_sun, float *outValue)
{
*outValue = 1.5; // initial 'fully lit' value
// simple tests
// if (EXPECT_NOT(e1 == e2 || e2 == the_sun))
*outValue = 1.5f; // initial 'fully lit' value
if (EXPECT_NOT(e1 == e2))
return NO; // you can't shade self
// (no longer needed; we rule out the others before this function)
// if (![e2 isShip] && ![e2 isPlanet])
// return NO; // only ships and planets shade.
//
{
// you can't shade self
return NO;
}
GLfloat cr_e2;
if ([e2 isShip])
{
@ -473,9 +472,12 @@ static BOOL entityByEntityOcclusionToValue(Entity *e1, Entity *e2, OOSunEntity *
cr_e2 = e2->collision_radius;
}
if (cr_e2 < e1->collision_radius)
return NO; // smaller can't shade bigger
// tested in construction of e2 list
{
// smaller can't shade bigger
return NO;
}
// tested in construction of e2 list
// if (e2->isSunlit == NO)
// return NO; // things already /in/ shade can't shade things more.
//
@ -483,52 +485,53 @@ static BOOL entityByEntityOcclusionToValue(Entity *e1, Entity *e2, OOSunEntity *
GLfloat d2_sun = distance2(e1->position, the_sun->position);
GLfloat d2_e2sun = distance2(e2->position, the_sun->position);
if (d2_e2sun > d2_sun)
return NO; // you are nearer the sun than the potential occluder, so it can't shade you
//
{
// you are nearer the sun than the potential occluder, so it can't shade you
return NO;
}
GLfloat d2_e2 = distance2( e1->position, e2->position);
GLfloat cr_sun = the_sun->collision_radius;
//
GLfloat cr2_sun_scaled = cr_sun * cr_sun * d2_e2 / d2_sun;
if (cr_e2 * cr_e2 < cr2_sun_scaled)
return NO; // if solar disc projected to the distance of e2 > collision radius it can't be shaded by e2
//
{
// if solar disc projected to the distance of e2 > collision radius it can't be shaded by e2
return NO;
}
// check angles subtended by sun and occluder
// double theta_sun = asin( cr_sun / sqrt(d2_sun)); // 1/2 angle subtended by sun
// double theta_e2 = asin( cr_e2 / sqrt(d2_e2)); // 1/2 angle subtended by e2
// find the difference between the angles subtended by occluder and sun
double theta_diff = asin(cr_e2 / sqrt(d2_e2)) - asin(cr_sun / sqrt(d2_sun));
float theta_diff = asinf(cr_e2 / sqrtf(d2_e2)) - asinf(cr_sun / sqrtf(d2_sun));
Vector p_sun = the_sun->position;
Vector p_e2 = e2->position;
Vector p_e1 = e1->position;
Vector v_sun = make_vector( p_sun.x - p_e1.x, p_sun.y - p_e1.y, p_sun.z - p_e1.z);
if (v_sun.x||v_sun.y||v_sun.z)
v_sun = vector_normal(v_sun);
else
v_sun.z = 1.0f;
//
Vector v_e2 = make_vector( p_e2.x - p_e1.x, p_e2.y - p_e1.y, p_e2.z - p_e1.z);
if (v_e2.x||v_e2.y||v_e2.z)
v_e2 = vector_normal(v_e2);
else
v_e2.x = 1.0f;
double phi = acos( dot_product( v_sun, v_e2)); // angle between sun and e2 from e1's viewpoint
Vector v_sun = vector_subtract(p_sun, p_e1);
v_sun = vector_normal_or_zbasis(v_sun);
Vector v_e2 = vector_subtract(p_e2, p_e1);
v_e2 = vector_normal_or_xbasis(v_e2);
float phi = acosf(dot_product(v_sun, v_e2)); // angle between sun and e2 from e1's viewpoint
*outValue = (phi / theta_diff); // 1 means just occluded, < 1 means in shadow
//
//if (theta_sun + phi > theta_e2)
if (phi > theta_diff)
return NO; // sun is not occluded
//
{
// sun is not occluded
return NO;
}
// all tests done e1 is in shade!
//
return YES;
}
static BOOL testEntityOccludedByEntity(Entity *e1, Entity *e2, OOSunEntity *the_sun)
static inline BOOL testEntityOccludedByEntity(Entity *e1, Entity *e2, OOSunEntity *the_sun)
{
double tmp; // we're not interested in the amount of occlusion just now.
float tmp; // we're not interested in the amount of occlusion just now.
return entityByEntityOcclusionToValue(e1, e2, the_sun, &tmp);
}
@ -637,7 +640,7 @@ static BOOL testEntityOccludedByEntity(Entity *e1, Entity *e2, OOSunEntity *the_
// test planets
for (j = 0; j < n_planets; j++)
{
double occlusionNumber;
float occlusionNumber;
if (entityByEntityOcclusionToValue(e1, planets[j], the_sun, &occlusionNumber))
{
e1->isSunlit = NO;