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fine-tuning of map generator and server and stuff.

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This commit is contained in:
Perttu Ahola 2011-01-17 02:40:53 +02:00
parent 7068bc90af
commit 3891bc43e0
11 changed files with 298 additions and 113 deletions
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55
src/utility.cpp
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@ -24,6 +24,7 @@ with this program; if not, write to the Free Software Foundation, Inc.,
#include "utility.h"
#include "irrlichtwrapper.h"
#include "gettime.h"
#include "mapblock.h"
TimeTaker::TimeTaker(const char *name, u32 *result)
{
@ -328,4 +329,58 @@ lopuks sit otetaan a/b
}
#endif
/*
blockpos: position of block in block coordinates
camera_pos: position of camera in nodes
camera_dir: an unit vector pointing to camera direction
range: viewing range
*/
bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir, f32 range)
{
v3s16 blockpos_nodes = blockpos_b * MAP_BLOCKSIZE;
// Block center position
v3f blockpos(
((float)blockpos_nodes.X + MAP_BLOCKSIZE/2) * BS,
((float)blockpos_nodes.Y + MAP_BLOCKSIZE/2) * BS,
((float)blockpos_nodes.Z + MAP_BLOCKSIZE/2) * BS
);
// Block position relative to camera
v3f blockpos_relative = blockpos - camera_pos;
// Distance in camera direction (+=front, -=back)
f32 dforward = blockpos_relative.dotProduct(camera_dir);
// Total distance
f32 d = blockpos_relative.getLength();
// If block is far away, it's not in sight
if(d > range * BS)
return false;
// Maximum radius of a block
f32 block_max_radius = 0.5*1.44*1.44*MAP_BLOCKSIZE*BS;
// If block is (nearly) touching the camera, don't
// bother validating further (that is, render it anyway)
if(d > block_max_radius * 1.5)
{
// Cosine of the angle between the camera direction
// and the block direction (camera_dir is an unit vector)
f32 cosangle = dforward / d;
// Compensate for the size of the block
// (as the block has to be shown even if it's a bit off FOV)
// This is an estimate.
cosangle += block_max_radius / dforward;
// If block is not in the field of view, skip it
//if(cosangle < cos(FOV_ANGLE/2))
if(cosangle < cos(FOV_ANGLE/2. * 4./3.))
return false;
}
return true;
}