diff options
Diffstat (limited to 'src/util/numeric.cpp')
-rw-r--r-- | src/util/numeric.cpp | 33 |
1 files changed, 17 insertions, 16 deletions
diff --git a/src/util/numeric.cpp b/src/util/numeric.cpp index ed83df7d7..0e2772c32 100644 --- a/src/util/numeric.cpp +++ b/src/util/numeric.cpp @@ -159,40 +159,41 @@ bool isBlockInSight(v3s16 blockpos_b, v3f camera_pos, v3f camera_dir, // 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(distance_ptr) *distance_ptr = d; - // If block is very close, it is always in sight - if(d < 1.44*1.44*MAP_BLOCKSIZE*BS/2) - return true; - // If block is far away, it's not in sight if(d > range) return false; - // Maximum radius of a block - f32 block_max_radius = 0.5*1.44*1.44*MAP_BLOCKSIZE*BS; + // Maximum radius of a block. The magic number is + // sqrt(3.0) / 2.0 in literal form. + f32 block_max_radius = 0.866025403784 * 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) return true; - + + // Adjust camera position, for purposes of computing the angle, + // such that a block that has any portion visible with the + // current camera position will have the center visible at the + // adjusted postion + f32 adjdist = block_max_radius / cos((M_PI - camera_fov) / 2); + + // Block position relative to adjusted camera + v3f blockpos_adj = blockpos - (camera_pos - camera_dir * adjdist); + + // Distance in camera direction (+=front, -=back) + f32 dforward = blockpos_adj.dotProduct(camera_dir); + // Cosine of the angle between the camera direction // and the block direction (camera_dir is an unit vector) - f32 cosangle = dforward / d; + f32 cosangle = dforward / blockpos_adj.getLength(); - // 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, plus an arbitary factor - cosangle += block_max_radius / d * 0.5; - // If block is not in the field of view, skip it if(cosangle < cos(camera_fov / 2)) return false; |