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Started functional decomposition for dynamic objects.

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Fixed typo in last patch, where objects were using object_group_lod
rather than object_lod.
This commit is contained in:
david 2002-07-16 23:39:53 +00:00
parent 8dc38a5198
commit f71f4cf9ab
1 changed files with 88 additions and 55 deletions
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143
src/Objects/obj.cxx
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@ -313,6 +313,83 @@ static void gen_random_surface_points( ssgLeaf *leaf, ssgVertexArray *lights,
}
/**
* Add an object to a random location inside a triangle.
*
* @param p1 The first vertex of the triangle.
* @param p2 The second vertex of the triangle.
* @param p3 The third vertex of the triangle.
* @param center The center of the triangle.
* @param ROT The world-up rotation matrix.
* @param mat The material object.
* @param object_index The index of the dynamically-placed object in
* the material.
* @param branch The branch where the object should be added to the
* scene graph.
*/
static void
add_object_to_triangle (sgVec3 p1, sgVec3 p2, sgVec3 p3, sgVec3 center,
sgMat4 ROT, FGNewMat * mat, int object_index,
ssgBranch * branch)
{
sgVec3 result;
random_pt_inside_tri(result, p1, p2, p3);
sgSubVec3(result, center);
sgMat4 OBJ_pos, OBJ;
sgMakeTransMat4(OBJ_pos, result);
sgCopyMat4(OBJ, ROT);
sgPostMultMat4(OBJ, OBJ_pos);
ssgTransform * pos = new ssgTransform;
pos->setTransform(OBJ);
float obj_range = mat->get_object_lod(object_index);
float range_div = (sg_random() * obj_range);
if (range_div < 0.0000001) {
// avoid a divide by zero error
range_div = 1.0;
}
float random_range = 160.0 * obj_range / range_div + obj_range;
float ranges[] = {0, random_range};
ssgRangeSelector *range = new ssgRangeSelector;
range->setRanges(ranges, 2);
range->addKid(mat->get_object(object_index));
pos->addKid(range);
branch->addKid(pos);
}
/**
* Create a rotation matrix to align an object for the current lat/lon.
*
* By default, objects are aligned for the north pole. This code
* calculates a matrix to rotate them for the surface of the earth in
* the current location.
*
* TODO: there should be a single version of this method somewhere
* for all of SimGear.
*
* @param ROT The resulting rotation matrix.
* @param hdg_deg The object heading in degrees.
* @param lon_deg The longitude in degrees.
* @param lat_deg The latitude in degrees.
*/
static void
makeWorldUpRotationMatrix (sgMat4 ROT, double hdg_deg,
double lon_deg, double lat_deg)
{
sgVec3 obj_right, obj_up;
sgSetVec3(obj_right, 0.0, 1.0, 0.0); // Y axis
sgSetVec3(obj_up, 0.0, 0.0, 1.0); // Z axis
sgMat4 ROT_lon, ROT_lat, ROT_hdg;
sgMakeRotMat4(ROT_lon, lon_deg, obj_up);
sgMakeRotMat4(ROT_lat, 90 - lat_deg, obj_right);
sgMakeRotMat4(ROT_hdg, hdg_deg, obj_up);
sgCopyMat4(ROT, ROT_hdg);
sgPostMultMat4(ROT, ROT_lat);
sgPostMultMat4(ROT, ROT_lon);
}
static void
gen_random_surface_objects (ssgLeaf *leaf,
ssgBranch *branch,
@ -330,20 +407,8 @@ gen_random_surface_objects (ssgLeaf *leaf,
float hdg_deg = 0.0; // do something here later
// The object will be aligned for the north pole. This code
// calculates a matrix to rotate it to for the surface of the
// earth in the current location.
sgVec3 obj_right, obj_up;
sgSetVec3(obj_right, 0.0, 1.0, 0.0); // Y axis
sgSetVec3(obj_up, 0.0, 0.0, 1.0); // Z axis
sgMat4 ROT_lon, ROT_lat, ROT_hdg;
sgMakeRotMat4(ROT_lon, lon_deg, obj_up);
sgMakeRotMat4(ROT_lat, 90 - lat_deg, obj_right);
sgMakeRotMat4(ROT_hdg, hdg_deg, obj_up);
sgMat4 ROT;
sgCopyMat4(ROT, ROT_hdg);
sgPostMultMat4(ROT, ROT_lat);
sgPostMultMat4(ROT, ROT_lon);
makeWorldUpRotationMatrix(ROT, hdg_deg, lon_deg, lat_deg);
if ( num > 0 ) {
short int n1, n2, n3;
@ -383,27 +448,8 @@ gen_random_surface_objects (ssgLeaf *leaf,
// place an object each unit of area
while ( num > 1.0 ) {
random_pt_inside_tri( result, p1, p2, p3 );
sgSubVec3(result, center);
sgMat4 OBJ_pos, OBJ;
sgMakeTransMat4(OBJ_pos, result);
sgCopyMat4(OBJ, ROT);
sgPostMultMat4(OBJ, OBJ_pos);
ssgTransform * pos = new ssgTransform;
pos->setTransform(OBJ);
float obj_range = mat->get_object_lod(j);
float range_div = (sg_random() * obj_range);
if (range_div < 0.0000001) {
// avoid a divide by zero error
range_div = 1.0;
}
float random_range = 160.0 * obj_range / range_div + obj_range;
float ranges[] = {0, random_range};
ssgRangeSelector *range = new ssgRangeSelector;
range->setRanges(ranges, 2);
range->addKid(mat->get_object(j));
pos->addKid(range);
location->addKid(pos);
add_object_to_triangle(p1, p2, p3, center,
ROT, mat, j, location);
num -= 1.0;
}
// for partial units of area, use a zombie door method to
@ -412,27 +458,8 @@ gen_random_surface_objects (ssgLeaf *leaf,
if ( num > 0.0 ) {
if ( sg_random() <= num ) {
// a zombie made it through our door
random_pt_inside_tri( result, p1, p2, p3 );
sgSubVec3(result, center);
sgMat4 OBJ_pos, OBJ;
sgMakeTransMat4(OBJ_pos, result);
sgCopyMat4(OBJ, ROT);
sgPostMultMat4(OBJ, OBJ_pos);
ssgTransform * pos = new ssgTransform;
pos->setTransform(OBJ);
float obj_range = mat->get_object_lod(j);
float range_div = (sg_random() * obj_range);
if (range_div < 0.0000001) {
// avoid a divide by zero error
range_div = 1.0;
}
float random_range = 160.0 * obj_range / range_div + obj_range;
float ranges[] = {0, random_range};
ssgRangeSelector *range = new ssgRangeSelector;
range->setRanges(ranges, 2);
range->addKid(mat->get_object(j));
pos->addKid(range);
location->addKid(pos);
add_object_to_triangle(p1, p2, p3, center,
ROT, mat, j, location);
}
}
}
@ -441,6 +468,12 @@ gen_random_surface_objects (ssgLeaf *leaf,
}
////////////////////////////////////////////////////////////////////////
// Scenery loaders.
////////////////////////////////////////////////////////////////////////
// Load an Ascii obj file
ssgBranch *fgAsciiObjLoad( const string& path, FGTileEntry *t,
ssgVertexArray *lights, const bool is_base)