Pre-initialize the variables driving the external force

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

diff --git a/simgear/scene/sky/cloud.cxx b/simgear/scene/sky/cloud.cxx
index e64d8648ad4332f402c2f8423402c6de5aa7cde5..e1f65de314e33e65190eb7ab563011e3502c472e 100644 (file)
--- a/simgear/scene/sky/cloud.cxx
+++ b/simgear/scene/sky/cloud.cxx
@@ -32,8 +32,9 @@
 
 #include "cloud.hxx"
 
-ssgSimpleState *
-SGCloudLayer::layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
+
+static ssgSimpleState *layer_states[SGCloudLayer::SG_MAX_CLOUD_COVERAGES];
+static bool state_initialized = false;
 
 
 // Constructor
@@ -47,6 +48,8 @@ SGCloudLayer::SGCloudLayer( const string &tex_path ) :
     layer_transition(0.0),
     layer_coverage(SG_CLOUD_CLEAR),
     scale(4000.0),
+    speed(0.0),
+    direction(0.0),
     last_lon(0.0),
     last_lat(0.0)
 {
@@ -55,9 +58,6 @@ SGCloudLayer::SGCloudLayer( const string &tex_path ) :
     tl[0] = tl[1] = tl[2] = tl[3] = NULL;
     layer[0] = layer[1] = layer[2] = layer[3] = NULL;
 
-    for ( int i = 0; i < SG_MAX_CLOUD_COVERAGES; ++i ) {
-        layer_states[i] = NULL;
-    }
     layer_root->addKid(layer_transform);
     rebuild();
 }
@@ -139,33 +139,37 @@ SGCloudLayer::setCoverage (Coverage coverage)
 void
 SGCloudLayer::rebuild()
 {
-                               // Initialize states and sizes if necessary.
-    if ( layer_states[0] == NULL ) {
+    // Initialize states and sizes if necessary.
+    if ( !state_initialized ) { 
+        state_initialized = true;
+
+        cout << "initializing cloud layers" << endl;
+
         SGPath cloud_path;
 
         cloud_path.set(texture_path.str());
         cloud_path.append("overcast.rgb");
-        layer_states[SG_CLOUD_OVERCAST] = SGCloudMakeState(cloud_path.str());
+        layer_states[SG_CLOUD_OVERCAST] = sgCloudMakeState(cloud_path.str());
 
         cloud_path.set(texture_path.str());
         cloud_path.append("broken.rgba");
         layer_states[SG_CLOUD_BROKEN]
-            = SGCloudMakeState(cloud_path.str());
+            = sgCloudMakeState(cloud_path.str());
 
         cloud_path.set(texture_path.str());
         cloud_path.append("scattered.rgba");
         layer_states[SG_CLOUD_SCATTERED]
-            = SGCloudMakeState(cloud_path.str());
+            = sgCloudMakeState(cloud_path.str());
 
         cloud_path.set(texture_path.str());
         cloud_path.append("few.rgba");
         layer_states[SG_CLOUD_FEW]
-            = SGCloudMakeState(cloud_path.str());
+            = sgCloudMakeState(cloud_path.str());
 
         cloud_path.set(texture_path.str());
         cloud_path.append("cirrus.rgba");
         layer_states[SG_CLOUD_CIRRUS]
-            = SGCloudMakeState(cloud_path.str());
+            = sgCloudMakeState(cloud_path.str());
 
         layer_states[SG_CLOUD_CLEAR] = 0;
     }
@@ -283,7 +287,7 @@ bool SGCloudLayer::repaint( sgVec3 fog_color ) {
 // 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,
-                              double alt )
+                              double alt, double dt )
 {
     sgMat4 T1, LON, LAT;
     sgVec3 axis;
@@ -341,15 +345,35 @@ bool SGCloudLayer::reposition( sgVec3 p, sgVec3 up, double lon, double lat,
         last_lat = lat;
     }
 
-    if ( lon != last_lon || lat != last_lat ) {
+    double sp_dist = speed*dt;
+
+    if ( lon != last_lon || lat != last_lat || sp_dist != 0 ) {
         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 );
+        double course = 0.0, dist = 0.0;
+
+        if (dest != start) {
+            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);
+
+        // calculate cloud movement due to external forces
+        double ax = 0.0, ay = 0.0, bx = 0.0, by = 0.0;
+
+        if (dist > 0.0) {
+            ax = cos(course) * dist;
+            ay = sin(course) * dist;
+        }
+
+        if (sp_dist > 0) {
+            bx = cos(-direction * SGD_DEGREES_TO_RADIANS) * sp_dist;
+            by = sin(-direction * SGD_DEGREES_TO_RADIANS) * sp_dist;
+        }
+
+
+        double xoff = (ax + bx) / (2 * scale);
+        double yoff = (ay + by) / (2 * scale);
 
         const float layer_scale = layer_span / scale;
 
@@ -424,9 +448,11 @@ void SGCloudLayer::draw() {
 
 
 // make an ssgSimpleState for a cloud layer given the named texture
-ssgSimpleState *SGCloudMakeState( const string &path ) {
+ssgSimpleState *sgCloudMakeState( const string &path ) {
     ssgSimpleState *state = new ssgSimpleState();
 
+    cout << " texture = " << path << endl;
+
     state->setTexture( (char *)path.c_str() );
     state->setShadeModel( GL_SMOOTH );
     state->disable( GL_LIGHTING );