commit 693d9c633d293a63756924b03f4fade44de94925
parent 2226e05667eb32b0b117bc15216ea7952dcc0a25
Author: Vincent Forest <vincent.forest@meso-star.com>
Date: Thu, 2 Mar 2017 16:32:19 +0100
Add an "auto look at" in rendering mode
If no position and no target is explicitly defined through the -r
option, automatically compute the rendering point of view to ensure that
the whole scene is visible.
Diffstat:
3 files changed, 111 insertions(+), 11 deletions(-)
diff --git a/src/solstice.c b/src/solstice.c
@@ -44,7 +44,6 @@
#include <unistd.h>
#endif
-
#include <solstice/ssol.h>
/*******************************************************************************
@@ -95,10 +94,99 @@ clear_nodes(struct darray_nodes* nodes)
}
static res_T
+auto_look_at
+ (struct ssol_scene* scn,
+ const double fov_x, /* Horizontal field of view in radian */
+ const double proj_ratio, /* Width / height */
+ const double up[3], /* Up vector */
+ double position[3],
+ double target[3])
+{
+ float flower[3], fupper[3];
+ double lower[3], upper[3];
+ double up_abs[3];
+ double axis_min[3];
+ double axis_x[3];
+ double axis_z[3];
+ double tmp[3];
+ double radius;
+ double depth;
+ res_T res;
+ ASSERT(scn && fov_x && proj_ratio && up);
+
+ res = ssol_scene_compute_aabb(scn, flower, fupper);
+ if(res != RES_OK) {
+ fprintf(stderr, "Couldn't compute the scene bounding box.\n");
+ goto error;
+ }
+
+ if(flower[0] > fupper[0]
+ || flower[1] > fupper[1]
+ || flower[2] > fupper[2]) { /* Empty scene */
+ d3_set(position, SOLSTICE_ARGS_DEFAULT.camera.pos);
+ d3_set(target, SOLSTICE_ARGS_DEFAULT.camera.tgt);
+ goto exit;
+ }
+
+ d3_set_f3(upper, fupper);
+ d3_set_f3(lower, flower);
+
+ /* The target is the scene centroid */
+ d3_muld(target, d3_add(target, lower, upper), 0.5);
+
+ /* Define which up dimension is minimal and use its unit vector to compute a
+ * vector orthogonal to `up'. This ensures that the unit vector and `up' are
+ * not collinear and thus that their cross product is not a zero vector. */
+ up_abs[0] = fabs(up[0]);
+ up_abs[1] = fabs(up[1]);
+ up_abs[2] = fabs(up[2]);
+ if(up_abs[0] < up_abs[1]) {
+ if(up_abs[0] < up_abs[2]) d3(axis_min, 1, 0, 0);
+ else d3(axis_min, 0, 0, 1);
+ } else {
+ if(up_abs[1] < up_abs[2]) d3(axis_min, 0, 1, 0);
+ else d3(axis_min, 0, 0, 1);
+ }
+ d3_normalize(axis_x, d3_cross(axis_x, up, axis_min));
+ d3_normalize(axis_z, d3_cross(axis_z, up, axis_x));
+
+ /* Approximate whether on the XYZ or the ZYX basis the visible part of the
+ * model is maximise */
+ if(fabs(d3_dot(axis_x, upper)) < fabs(d3_dot(axis_z, upper))) {
+ SWAP(double, axis_x[0], axis_z[0]);
+ SWAP(double, axis_x[1], axis_z[1]);
+ SWAP(double, axis_x[2], axis_z[2]);
+ }
+
+ /* Ensure that the whole model is visible */
+ radius = d3_len(d3_sub(tmp, upper, lower)) * 0.5;
+ if(proj_ratio < 1) {
+ depth = radius / sin(fov_x/2.0);
+ } else {
+ depth = radius / sin(fov_x/(2.0*proj_ratio));
+ }
+
+ /* Define the camera position */
+ d3_sub(position, target, d3_muld(tmp, axis_z, depth));
+
+ /* Empirically move the position to find a better point of view */
+ d3_add(position, position, d3_muld(tmp, up, radius)); /*Empirical offset*/
+ d3_add(position, position, d3_muld(tmp, axis_x, radius)); /*Empirical offset*/
+ d3_normalize(tmp, d3_sub(tmp, target, position));
+ d3_sub(position, target, d3_muld(tmp, tmp, depth));
+
+exit:
+ return res;
+error:
+ goto exit;
+}
+
+static res_T
setup_camera(struct solstice* solstice, const struct solstice_args* args)
{
struct ssol_camera* cam = NULL;
double proj_ratio = 0;
+ double pos[3], tgt[3];
res_T res = RES_OK;
ASSERT(solstice && args);
@@ -122,8 +210,16 @@ setup_camera(struct solstice* solstice, const struct solstice_args* args)
goto error;
}
- res = ssol_camera_look_at
- (cam, args->camera.pos, args->camera.tgt, args->camera.up);
+ if(!args->camera.auto_look_at) {
+ d3_set(pos, args->camera.pos);
+ d3_set(tgt, args->camera.tgt);
+ } else {
+ res = auto_look_at(solstice->scene, MDEG2RAD(args->camera.fov_x),
+ proj_ratio, args->camera.up, pos, tgt);
+ if(res != RES_OK) goto error;
+ }
+
+ res = ssol_camera_look_at(cam, pos, tgt, args->camera.up);
if(res != RES_OK) {
fprintf(stderr,
"Invalid camera point of view:\n"
@@ -462,13 +558,6 @@ solstice_init
goto error;
}
- if(args->rendering) {
- res = setup_camera(solstice, args);
- if(res != RES_OK) goto error;
- res = setup_framebuffer(solstice, args);
- if(res != RES_OK) goto error;
- }
-
res = setup_sun_dirs(solstice, args);
if(res != RES_OK) goto error;
@@ -505,6 +594,13 @@ solstice_init
solstice->dump_format = args->dump_format;
solstice->dump_split_mode = args->dump_split_mode;
+ if(args->rendering) {
+ res = setup_camera(solstice, args);
+ if(res != RES_OK) goto error;
+ res = setup_framebuffer(solstice, args);
+ if(res != RES_OK) goto error;
+ }
+
exit:
return res;
error:
diff --git a/src/solstice_args.c b/src/solstice_args.c
@@ -238,6 +238,7 @@ parse_rendering_option(const char* str, struct solstice_args* args)
fprintf(stderr, "Invalid camera position `%s'.\n", val);
goto error;
}
+ args->camera.auto_look_at = 0; /* Disable auto look at */
} else if(!strcmp(key, "tgt")) {
res = cstr_to_list_double(val, ',', args->camera.tgt, &len, 3);
if(res == RES_OK && len != 3) res = RES_BAD_ARG;
@@ -245,6 +246,7 @@ parse_rendering_option(const char* str, struct solstice_args* args)
fprintf(stderr, "Invalid camera target `%s'.\n", val);
goto error;
}
+ args->camera.auto_look_at = 0; /* Disable auto look at */
} else if(!strcmp(key, "up")) {
res = cstr_to_list_double(val, ',', args->camera.up, &len, 3);
if(res == RES_OK && len != 3) res = RES_BAD_ARG;
diff --git a/src/solstice_args.h.in b/src/solstice_args.h.in
@@ -51,6 +51,7 @@ struct solstice_args {
double tgt[3];
double up[3];
double fov_x; /* In radians */
+ int auto_look_at;
} camera;
struct {
@@ -85,7 +86,8 @@ static const struct solstice_args SOLSTICE_ARGS_NULL = SOLSTICE_ARGS_NULL__;
{ @SOLSTICE_ARGS_DEFAULT_CAMERA_POS@ }, \
{ @SOLSTICE_ARGS_DEFAULT_CAMERA_TGT@ }, \
{ @SOLSTICE_ARGS_DEFAULT_CAMERA_UP@ }, \
- @SOLSTICE_ARGS_DEFAULT_CAMERA_FOV@ \
+ @SOLSTICE_ARGS_DEFAULT_CAMERA_FOV@, \
+ 1, \
}, \
\
{ /* Image */ \
