A couple more cloud tweaks.

[simgear.git] / simgear / sky / cloud.cxx

diff --git a/simgear/sky/cloud.cxx b/simgear/sky/cloud.cxx
index 147f80788a2f87dd88cef678e24102f0e15769fe..e6d02c5c7c6ee72989c36a986eca7b0a3c85dc4f 100644 (file)
--- a/simgear/sky/cloud.cxx
+++ b/simgear/sky/cloud.cxx
@@ -26,6 +26,9 @@
 #include <plib/ssg.h>
 
 #include <simgear/constants.h>
+#include <simgear/math/fg_random.h>
+#include <simgear/math/point3d.hxx>
+#include <simgear/math/polar3d.hxx>
 
 #include "cloud.hxx"
 
@@ -41,9 +44,17 @@ SGCloudLayer::~SGCloudLayer( void ) {
 
 
 // build the moon object
-ssgBranch * SGCloudLayer::build( FGPath path, double size, double asl ) {
+void SGCloudLayer::build( FGPath path, double s, double asl, double thickness,
+                         double transition )
+{
+    scale = 4000.0;
 
     layer_asl = asl;
+    layer_thickness = thickness;
+    layer_transition = transition;
+
+    size = s;
+    last_lon = last_lat = -999.0f;
 
     // set up the cloud state
     path.append( "cloud.rgba" );
@@ -72,25 +83,27 @@ ssgBranch * SGCloudLayer::build( FGPath path, double size, double asl ) {
     sgSetVec4( color, 1.0f, 1.0f, 1.0f, 1.0f );
 
     sgSetVec3( vertex, -size, -size, 0.0f );
-    sgSetVec2( tc, 0.0f, 0.0f );
+    sgVec2 base;
+    sgSetVec2( base, fg_random(), fg_random() );
+    sgSetVec2( tc, base[0], base[1] );
     cl->add( color );
     vl->add( vertex );
     tl->add( tc );
 
     sgSetVec3( vertex, size, -size, 0.0f );
-    sgSetVec2( tc, size / 1000.0f, 0.0f );
+    sgSetVec2( tc, base[0] + size / scale, base[1] );
     cl->add( color );
     vl->add( vertex );
     tl->add( tc );
 
     sgSetVec3( vertex, -size, size, 0.0f );
-    sgSetVec2( tc, 0.0f, size / 1000.0f );
+    sgSetVec2( tc, base[0], base[1] + size / scale );
     cl->add( color );
     vl->add( vertex );
     tl->add( tc );
 
     sgSetVec3( vertex, size, size, 0.0f );
-    sgSetVec2( tc, size / 1000.0f, size / 1000.0f );
+    sgSetVec2( tc, base[0] + size / scale, base[1] + size / scale );
     cl->add( color );
     vl->add( vertex );
     tl->add( tc );
@@ -109,7 +122,8 @@ ssgBranch * SGCloudLayer::build( FGPath path, double size, double asl ) {
     // moon_transform->addKid( halo );
     layer_transform->addKid( layer );
 
-    return layer_transform;
+    layer_root = new ssgRoot;
+    layer_root->addKid( layer_transform );
 }
 
 
@@ -131,7 +145,9 @@ bool SGCloudLayer::repaint( sgVec3 fog_color ) {
 // lat specifies a rotation about the new Y axis
 // spin specifies a rotation about the new Z axis (and orients the
 // sunrise/set effects
-bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat ) {
+bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat,
+                              double alt )
+{
     sgMat4 T1, LON, LAT;
     sgVec3 axis;
 
@@ -139,7 +155,11 @@ bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat ) {
     sgVec3 asl_offset;
     sgCopyVec3( asl_offset, up );
     sgNormalizeVec3( asl_offset );
-    sgScaleVec3( asl_offset, layer_asl );
+    if ( alt <= layer_asl ) {
+       sgScaleVec3( asl_offset, layer_asl );
+    } else {
+       sgScaleVec3( asl_offset, layer_asl + layer_thickness );
+    }
     // cout << "asl_offset = " << asl_offset[0] << "," << asl_offset[1]
     //      << "," << asl_offset[2] << endl;
     sgAddVec3( asl_offset, p );
@@ -176,5 +196,54 @@ bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat ) {
 
     layer_transform->setTransform( &layerpos );
 
+    // now calculate update texture coordinates
+    if ( last_lon < -900 ) {
+       last_lon = lon;
+       last_lat = lat;
+    }
+
+    if ( lon != last_lon || lat != last_lat ) {
+       Point3D start( last_lon, last_lat, 0.0 );
+       Point3D dest( lon, lat, 0.0 );
+       double course, dist;
+       calc_gc_course_dist( dest, start, &course, &dist );
+       // cout << "course = " << course << ", dist = " << dist << endl;
+
+       double xoff = cos( course ) * dist / (2 * scale);
+       double yoff = sin( course ) * dist / (2 * scale);
+
+       // cout << "xoff = " << xoff << ", yoff = " << yoff << endl;
+
+       float *base, *tc;
+       base = tl->get( 0 );
+
+       base[0] += xoff;
+       while ( base[0] > 1.0 ) { base[0] -= 1.0; }
+       while ( base[0] < 0.0 ) { base[0] += 1.0; }
+
+       base[1] += yoff;
+       while ( base[1] > 1.0 ) { base[1] -= 1.0; }
+       while ( base[1] < 0.0 ) { base[1] += 1.0; }
+
+       // cout << "base = " << base[0] << "," << base[1] << endl;
+
+       tc = tl->get( 1 );
+       sgSetVec2( tc, base[0] + size / scale, base[1] );
+ 
+       tc = tl->get( 2 );
+       sgSetVec2( tc, base[0], base[1] + size / scale );
+ 
+       tc = tl->get( 3 );
+       sgSetVec2( tc, base[0] + size / scale, base[1] + size / scale );
+ 
+       last_lon = lon;
+       last_lat = lat;
+    }
+
     return true;
 }
+
+
+void SGCloudLayer::draw() {
+    ssgCullAndDraw( layer_root );
+}