libgis -> grits: Fix build after rename

[grits] / src / plugins / env.c

diff --git a/src/plugins/env.c b/src/plugins/env.c
index e5787c6d6cead1d1837720735b1a9ce0a25f5c7a..129e759ea8d39b4ea4a4126a2adde2c5e3a7397f 100644 (file)
--- a/src/plugins/env.c
+++ b/src/plugins/env.c
@@ -15,18 +15,27 @@
  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  */
 
+/**
+ * SECTION:env
+ * @short_description: Environment plugin
+ *
+ * #GisPluginEnv provides environmental information such as sky images. It can
+ * also paint a blank overlay on the surface so that other plugins can draw
+ * transparent overlays nicely.
+ */
+
 #include <math.h>
 #include <gtk/gtkgl.h>
 #include <GL/gl.h>
 
-#include <gis.h>
+#include <grits.h>
 
 #include "env.h"
 
 /***********
  * Helpers *
  ***********/
-static gpointer expose(GisCallback *callback, gpointer _env)
+static void expose(GisCallback *callback, GisOpenGL *opengl, gpointer _env)
 {
        GisPluginEnv *env = GIS_PLUGIN_ENV(_env);
        g_debug("GisPluginEnv: expose");
@@ -35,46 +44,52 @@ static gpointer expose(GisCallback *callback, gpointer _env)
        gis_viewer_get_location(env->viewer, &lat, &lon, &elev);
 
        /* Misc */
-       gdouble rg   = MAX(0, 1-(elev/20000));
-       gdouble blue = MAX(0, 1-(elev/50000));
-       glClearColor(MIN(0.65,rg), MIN(0.65,rg), MIN(1,blue), 1.0f);
+       gdouble rg   = MAX(0, 1-(elev/40000));
+       gdouble blue = MAX(0, 1-(elev/100000));
+       glClearColor(MIN(0.4,rg), MIN(0.4,rg), MIN(1,blue), 1.0f);
        glClear(GL_COLOR_BUFFER_BIT);
 
        /* Attempt to render an atmosphere */
-       /*
        glEnable(GL_COLOR_MATERIAL);
        glDisable(GL_CULL_FACE);
        glDisable(GL_LIGHTING);
+       glMatrixMode(GL_MODELVIEW);
+       glBlendFunc(GL_SRC_ALPHA, GL_DST_ALPHA);
+       gis_viewer_center_position(env->viewer, lat, lon, -EARTH_R);
 
-       glBlendFunc(GL_ONE, GL_ONE);
+       gdouble ds  = EARTH_R+elev;     // distance to self
+       gdouble da  = EARTH_R+300000;   // distance to top of atmosphere
+       gdouble dg  = EARTH_R-100000;   // distance to top of atmosphere
+       gdouble ang = acos(EARTH_R/ds); // angle to horizon
+       ang = MAX(ang,0.1);
 
-       glMatrixMode(GL_MODELVIEW);
+       gdouble ar  = sin(ang)*da;      // top of quad fan "atomosphere"j
+       gdouble az  = cos(ang)*da;      //
 
-       elev = -EARTH_R;
-       for (elev = -EARTH_R; elev < 0; elev += EARTH_R/10) {
-               glPushMatrix();
-               glColor4f(0.3, 0.3, 1.0, 0.2);
-               gis_viewer_center_position(env->viewer, lat, lon, elev);
-
-               glBegin(GL_TRIANGLE_FAN);
-               glVertex3f(0, 0, 0);
-               for (gdouble i = 0; i <= 2*G_PI; i += G_PI/10) {
-                       gint rad = 1*EARTH_R + 300000;
-                       glVertex3f(rad*sin(i), rad*cos(i), 0);
-                       g_message("%f %f %f", 3*EARTH_R*sin(i), 3*EARTH_R*cos(i), 0.);
-               }
-               glEnd();
-               glPopMatrix();
-       }
-       */
+       gdouble gr  = sin(ang)*dg;      // bottom of quad fan "ground"
+       gdouble gz  = cos(ang)*dg;      //
 
-       return NULL;
+       glBegin(GL_QUAD_STRIP);
+       for (gdouble i = 0; i <= 2*G_PI; i += G_PI/30) {
+               glColor4f(0.3, 0.3, 1.0, 1.0); glVertex3f(gr*sin(i), gr*cos(i), gz);
+               glColor4f(0.3, 0.3, 1.0, 0.0); glVertex3f(ar*sin(i), ar*cos(i), az);
+       }
+       glEnd();
 }
 
 
 /***********
  * Methods *
  ***********/
+/**
+ * gis_plugin_env_new:
+ * @viewer: the #GisViewer to use for drawing
+ * @prefs:  the #GisPrefs for storing configurations
+ *
+ * Create a new instance of the environment plugin.
+ *
+ * Returns: the new #GisPluginEnv
+ */
 GisPluginEnv *gis_plugin_env_new(GisViewer *viewer, GisPrefs *prefs)
 {
        g_debug("GisPluginEnv: new");