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-rw-r--r--hacks/glx/glplanet.c206
1 files changed, 186 insertions, 20 deletions
diff --git a/hacks/glx/glplanet.c b/hacks/glx/glplanet.c
index a2f6889..83748cc 100644
--- a/hacks/glx/glplanet.c
+++ b/hacks/glx/glplanet.c
@@ -65,6 +65,7 @@
#define DEF_RESOLUTION "128"
#define DEF_IMAGE "BUILTIN"
#define DEF_IMAGE2 "BUILTIN"
+#define DEF_MODE "globe"
#define BLENDED_TERMINATOR
@@ -83,6 +84,7 @@ static char *which_image;
static char *which_image2;
static int resolution;
static GLfloat spin_arg;
+static char *mode_arg;
static XrmOptionDescRec opts[] = {
{"-rotate", ".rotate", XrmoptionNoArg, "true" },
@@ -96,9 +98,11 @@ static XrmOptionDescRec opts[] = {
{"-stars", ".stars", XrmoptionNoArg, "true" },
{"+stars", ".stars", XrmoptionNoArg, "false" },
{"-spin", ".spin", XrmoptionSepArg, 0 },
+ {"-no-spin", ".spin", XrmoptionNoArg, "0" },
{"-image", ".image", XrmoptionSepArg, 0 },
{"-image2", ".image2", XrmoptionSepArg, 0 },
{"-resolution", ".resolution", XrmoptionSepArg, 0 },
+ {"-mode", ".mode", XrmoptionSepArg, 0 },
};
static argtype vars[] = {
@@ -110,6 +114,7 @@ static argtype vars[] = {
{&spin_arg, "spin", "Spin", DEF_SPIN, t_Float},
{&which_image, "image", "Image", DEF_IMAGE, t_String},
{&which_image2,"image2", "Image", DEF_IMAGE2, t_String},
+ {&mode_arg, "mode" ,"Mode" , DEF_MODE, t_String},
{&resolution, "resolution","Resolution", DEF_RESOLUTION, t_Int},
};
@@ -154,6 +159,7 @@ typedef struct {
Bool button_down_p;
GLuint tex1, tex2;
int draw_axis;
+ enum { GLOBE, EQUIRECTANGULAR, MERCATOR } mode;
} planetstruct;
@@ -268,6 +274,138 @@ setup_texture (ModeInfo * mi)
static void
+unit_mercator (int stacks, int slices, int wire_p, Bool mercp)
+{
+ int i, j;
+ GLfloat x, y, ty, xs, ys;
+ GLfloat lastx = 0, lasty = 0, lastty = 0;
+ GLfloat r, north, south;
+
+ /* #### TODO: the grid lines are always rendered as Equirectangular,
+ not Mercator. */
+
+ stacks /= 2;
+ xs = 1.0 / slices;
+ ys = 1.0 / stacks;
+
+ glPushMatrix();
+ r = 1.8;
+ glScalef (r, r, r);
+ glFrontFace(GL_CW);
+
+ r = 0.35; /* Grids are roughly square at equator */
+
+ if (mercp)
+ {
+ /* The poles go to infinity. The traditional Mercator projection
+ omits the Northern and Southern latitudes asymmetrically to
+ move Europe toward the center. How Colonial! */
+ north = 85 / 180.0;
+ south = -66 / 180.0;
+ }
+ else
+ {
+ /* Antarctica should be roughly the same width as North America,
+ but even Equirectangular is crazypants here. */
+ north = 80 / 180.0;
+ south = -north;
+ }
+
+
+ for (j = 0, y = -0.5, ty = 0; j <= stacks;
+ lasty = y, lastty = ty, y += ys, j++)
+ {
+ GLfloat th;
+
+ ty = (0.5 - y) * (south - north) - south;
+ ty += 0.5;
+
+ th = M_PI * (ty - 0.5); /* latitude in radians */
+
+ if (mercp)
+ {
+ /* Obviously I have no idea what I'm doing here */
+ ty = 2 * (atan (pow(M_E, th)) - M_PI/4);
+ ty *= 0.41;
+ ty += 0.5;
+ }
+
+ /* Draw the end caps
+ */
+ if (j == 0 || j == stacks)
+ {
+ GLfloat xx, yy, lxx, lyy;
+ glFrontFace(j == 0 ? GL_CCW : GL_CW);
+
+ if (j == stacks && !wire_p) glEnd();
+
+ glNormal3f (0, (j == 0 ? -1 : 1), 0);
+
+ glBegin (wire_p ? GL_LINE_LOOP : GL_TRIANGLES);
+
+ for (i = 0, x = 0, lastx = 0, lxx = 0;
+ i <= slices;
+ lastx = x, lxx = xx, lyy = yy, x += xs, i++)
+ {
+ xx = r * cos(M_PI * 2 * x);
+ yy = r * sin(M_PI * 2 * x);
+ if (i == 0) continue;
+
+ glTexCoord2f (x, j == 0 ? 0 : 1);
+ glVertex3f (0, y, 0);
+ glTexCoord2f (lastx, ty); glVertex3f (lxx, y, lyy);
+ glTexCoord2f (x, ty); glVertex3f (xx, y, yy);
+ }
+ glEnd();
+ glFrontFace(GL_CW);
+
+ if (!wire_p) glBegin (GL_QUADS);
+ }
+
+ if (j == 0)
+ continue;
+
+ /* Draw one ring of quads.
+ */
+ for (i = 0, x = 0, lastx = 0; i <= slices; lastx = x, x += xs, i++)
+ {
+ GLfloat xx = r * cos(M_PI * 2 * x);
+ GLfloat yy = r * sin(M_PI * 2 * x);
+ GLfloat lx = r * cos(M_PI * 2 * lastx);
+ GLfloat ly = r * sin(M_PI * 2 * lastx);
+ GLfloat y2 = y;
+ GLfloat ly2 = lasty;
+
+#if 0
+ if (mercp)
+ {
+ y2 = ty - 0.5;
+ ly2 = lastty - 0.5;
+ }
+#endif
+
+ if (i == 0) continue;
+ if (wire_p) glBegin(GL_LINE_LOOP);
+ glNormal3f (lx, 0, ly);
+ glTexCoord2f (lastx, lastty); glVertex3f (lx, ly2, ly);
+ glNormal3f (xx, 0, yy);
+ glTexCoord2f (x, lastty); glVertex3f (xx, ly2, yy);
+ glNormal3f (xx, 0, yy);
+ glTexCoord2f (x, ty); glVertex3f (xx, y2, yy);
+ glNormal3f (lx, 0, ly);
+ glTexCoord2f (lastx, ty); glVertex3f (lx, y2, ly);
+ if (wire_p) glEnd();
+ }
+ }
+
+ if (!wire_p) glEnd();
+
+ glPopMatrix();
+}
+
+
+
+static void
init_stars (ModeInfo *mi)
{
planetstruct *gp = &planets[MI_SCREEN(mi)];
@@ -452,6 +590,20 @@ init_planet (ModeInfo * mi)
reshape_planet(mi, MI_WIDTH(mi), MI_HEIGHT(mi));
}
+ if (!mode_arg || !*mode_arg || !strcasecmp(mode_arg, "GLOBE"))
+ gp->mode = GLOBE;
+ else if (!strcasecmp(mode_arg, "EQUIRECTANGULAR"))
+ gp->mode = EQUIRECTANGULAR;
+ else if (!strcasecmp(mode_arg, "mercator"))
+ gp->mode = MERCATOR;
+ else
+ {
+ fprintf (stderr,
+ "%s: mode must be 'globe', 'merecator' or 'equirectangular',"
+ " not '%s'\n", progname, mode_arg);
+ exit (1);
+ }
+
{
char *f = get_string_resource(mi->dpy, "imageForeground", "Foreground");
char *b = get_string_resource(mi->dpy, "imageBackground", "Background");
@@ -513,7 +665,10 @@ init_planet (ModeInfo * mi)
glFrontFace(GL_CCW);
glPushMatrix();
glRotatef (90, 1, 0, 0);
- unit_sphere (resolution, resolution, wire);
+ if (gp->mode == GLOBE)
+ unit_sphere (resolution, resolution, wire);
+ else
+ unit_mercator (resolution, resolution, wire, (gp->mode == MERCATOR));
glPopMatrix();
glEndList();
@@ -533,24 +688,27 @@ init_planet (ModeInfo * mi)
}
# endif
- glPushMatrix();
- glScalef (1.01, 1.01, 1.01);
- unit_dome (resolution, resolution, wire);
-
-# ifdef BLENDED_TERMINATOR
- terminator_tube (mi, resolution);
- if (!wire)
+ if (gp->mode == GLOBE)
{
- /* We have to draw the transparent side of the mask too,
- though I'm not sure why. */
- GLfloat c[] = { 0, 0, 0, 0 };
- glColor4fv (c);
- if (!do_texture)
- glMaterialfv (GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, c);
- glRotatef (180, 1, 0, 0);
+ glPushMatrix();
+ glScalef (1.01, 1.01, 1.01);
unit_dome (resolution, resolution, wire);
- }
+
+# ifdef BLENDED_TERMINATOR
+ terminator_tube (mi, resolution);
+ if (!wire)
+ {
+ /* We have to draw the transparent side of the mask too,
+ though I'm not sure why. */
+ GLfloat c[] = { 0, 0, 0, 0 };
+ glColor4fv (c);
+ if (!do_texture)
+ glMaterialfv (GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE, c);
+ glRotatef (180, 1, 0, 0);
+ unit_dome (resolution, resolution, wire);
+ }
# endif
+ }
glPopMatrix();
glEndList();
@@ -562,8 +720,10 @@ init_planet (ModeInfo * mi)
glPushMatrix ();
glRotatef (90, 1, 0, 0); /* unit_sphere is off by 90 */
glRotatef (8, 0, 1, 0); /* line up the time zones */
- unit_sphere (12, 24, 1);
- unit_sphere (12, 24, 1);
+ if (gp->mode == GLOBE)
+ unit_sphere (12, 24, 1);
+ else
+ unit_mercator (20, 24, 1, (gp->mode == MERCATOR));
glBegin(GL_LINES);
glVertex3f(0, -2, 0);
glVertex3f(0, 2, 0);
@@ -599,7 +759,8 @@ draw_planet (ModeInfo * mi)
if (do_rotate && !gp->button_down_p)
{
- gp->z -= 0.001 * spin_arg; /* the sun sets in the west */
+ int wat = gp->mode == GLOBE ? 1 : -1;
+ gp->z -= 0.001 * spin_arg * wat; /* the sun sets in the west */
if (gp->z < 0) gp->z += 1;
}
@@ -685,7 +846,7 @@ draw_planet (ModeInfo * mi)
glPopMatrix();
}
- else if (!do_texture || gp->tex2)
+ else if (!do_texture || (gp->tex2 && gp->mode == GLOBE))
{
/* Originally we just used GL_LIGHT0 to produce the day/night sides of
the planet, but that always looked crappy, even with a vast number of
@@ -802,6 +963,11 @@ draw_planet (ModeInfo * mi)
#endif /* BLENDED_TERMINATOR */
}
+ else if (gp->mode != GLOBE)
+ {
+ glDisable (GL_LIGHTING);
+ glDisable (GL_BLEND);
+ }
if (gp->draw_axis)
{
generated by cgit v1.2.3-55-g7522 (git 2.39.0) at 2024-04-27 00:25:08 +0200