void DynamicSkyLight::SetLightParams(float4 newLightDir, float startAngle, float orbitTime) {
newLightDir.ANormalize();
sunStartAngle = PI + startAngle; //FIXME WHY +PI?
sunOrbitTime = orbitTime;
initialSunAngle = GetRadFromXY(newLightDir.x, newLightDir.z);
//FIXME This function really really needs comments about what it does!
if (newLightDir.w == FLT_MAX) {
// old: newLightDir is position where sun reaches highest altitude
const float sunLen = newLightDir.Length2D();
const float sunAzimuth = (sunLen <= 0.001f) ? PI / 2.0f : atan(newLightDir.y / sunLen);
const float sunHeight = tan(sunAzimuth - 0.001f);
float3 v1(cos(initialSunAngle), sunHeight, sin(initialSunAngle));
v1.ANormalize();
if (v1.y <= orbitMinSunHeight) {
newLightDir = UpVector;
sunOrbitHeight = v1.y;
sunOrbitRad = sqrt(1.0f - sunOrbitHeight * sunOrbitHeight);
} else {
float3 v2(cos(initialSunAngle + PI), orbitMinSunHeight, sin(initialSunAngle + PI));
v2.ANormalize();
float3 v3 = v2 - v1;
sunOrbitRad = v3.Length() / 2.0f;
v3.ANormalize();
float3 v4 = (v3.cross(UpVector)).ANormalize();
float3 v5 = (v3.cross(v4)).ANormalize();
if (v5.y < 0.0f)
v5 = -v5;
newLightDir = v5;
sunOrbitHeight = v5.dot(v1);
}
} else {
// new: newLightDir is center position of orbit, and newLightDir.w is orbit height
sunOrbitHeight = std::max(-1.0f, std::min(newLightDir.w, 1.0f));
sunOrbitRad = sqrt(1.0f - sunOrbitHeight * sunOrbitHeight);
}
sunRotation.LoadIdentity();
sunRotation.SetUpVector(newLightDir);
const float4& peakDir = CalculateSunPos(0.0f);
const float peakElev = std::max(0.01f, peakDir.y);
shadowDensityFactor = 1.0f / peakElev;
SetLightDir(CalculateSunPos(sunStartAngle).ANormalize());
}
void CDecalsDrawerGL4::CreateBuildingDecal(const CSolidObject* object)
{
const SolidObjectDecalDef& decalDef = object->GetDef()->decalDef;
if (!decalDef.useGroundDecal)
return;
const int sizex = decalDef.groundDecalSizeX;
const int sizey = decalDef.groundDecalSizeY;
Decal d;
d.pos = object->pos;
d.rot = GetRadFromXY(object->frontdir.x, object->frontdir.z) - fastmath::HALFPI;
d.size = float2(sizex * SQUARE_SIZE, sizey * SQUARE_SIZE);
d.alpha = 1.0f;
d.alphaFalloff = decalDef.groundDecalDecaySpeed;
d.SetTexture(decalDef.groundDecalTypeName);
d.type = Decal::BUILDING;
d.owner = object;
d.generation = gs->frameNum;
NewDecal(d);
}
