# HG changeset patch
# User Eleni Maria Stea <elene.mst@gmail.com>
# Date 1391300288 -7200
# Node ID 1272e33356082a99c11e039f733c62f4a4b12bbd
# Parent  c5af275b6a600a6771796b47071ae2c5acd03123
using 2 thresholds (sigmoid functions)
custom resolution in polygonization

diff -r c5af275b6a60 -r 1272e3335608 notes
--- a/notes	Mon Jan 27 01:22:02 2014 +0200
+++ b/notes	Sun Feb 02 02:18:08 2014 +0200
@@ -1,4 +1,5 @@
-3d texture ap ta slices
-sunartisi pou na ftiaxnei to isosurface
-mesh class
-i volume class tha ftiaxnei ena mesh i 8a bazei data mesa s ena mesh
+Sigmoid 2
+k T=0,5 panta
+gia windowing
+
+na balw to t tou gui -1000 ws 1000 k na ginetai map sto 0 ws 1
diff -r c5af275b6a60 -r 1272e3335608 src/main.cc
--- a/src/main.cc	Mon Jan 27 01:22:02 2014 +0200
+++ b/src/main.cc	Sun Feb 02 02:18:08 2014 +0200
@@ -27,7 +27,7 @@
 
 static Volume *vol;
 static Mesh *mesh;
-static float cur_z, thres = 0.5;
+static float cur_z, thres = 0.5, thres2 = 1.0;
 
 static int use_orig_vol_res = 1;
 static int vol_res[3]; // volume sampling resolution x/y/z
@@ -106,9 +106,24 @@
 static void thres_change(int id)
 {
 	static float prev_thres = thres;
+	static float prev_thres2 = thres2;
 
-	if(prev_thres != thres) {
+	if(prev_thres != thres || prev_thres2 != thres2) {
 		prev_thres = thres;
+		prev_thres2 = thres2;
+		mesh->clear();
+	}
+}
+static void res_change(int id)
+{
+	static float prev_resx = vol_res[0];
+	static float prev_resy = vol_res[1];
+	static float prev_resz = vol_res[2];
+
+	if(prev_resx != vol_res[0] || prev_resy != vol_res[1] || prev_resz != vol_res[2]) {
+		prev_resx = vol_res[0];
+		prev_resy = vol_res[1];
+		prev_resz = vol_res[2];
 		mesh->clear();
 	}
 }
@@ -119,16 +134,21 @@
 
 	ui->set_main_gfx_window(glutGetWindow());
 
-	GLUI_Spinner *thres_spin = ui->add_spinner("iso threshold", GLUI_SPINNER_FLOAT, &thres, 0, thres_change);
+	GLUI_Panel *thres_panel = ui->add_panel("iso thresholds");
+
+	GLUI_Spinner *thres_spin = ui->add_spinner_to_panel(thres_panel, "T1", GLUI_SPINNER_FLOAT, &thres, 0, thres_change);
 	thres_spin->set_float_limits(0, 1);
 
+	GLUI_Spinner *thres2_spin = ui->add_spinner_to_panel(thres_panel, "T2", GLUI_SPINNER_FLOAT, &thres2, 0, thres_change);
+	thres2_spin->set_float_limits(0, 1);
+
 	GLUI_Panel *res_panel = ui->add_panel("volume resolution");
 
 	ui->add_checkbox_to_panel(res_panel, "original resolution", &use_orig_vol_res, 0, toggle_use_orig);
 
 	static const char *res_spin_name[] = {"x", "y", "z"};
 	for(int i=0; i<3; i++) {
-		res_spin[i] = ui->add_spinner_to_panel(res_panel, res_spin_name[i], GLUI_SPINNER_INT, vol_res + i);
+		res_spin[i] = ui->add_spinner_to_panel(res_panel, res_spin_name[i], GLUI_SPINNER_INT, vol_res + i, 0, res_change);
 		res_spin[i]->set_int_limits(8, 256); // TODO limits as arguments or config
 		res_spin[i]->disable();
 	}
@@ -161,7 +181,7 @@
 	if(mesh->is_empty()) {
 		printf("recalculating isosurface ... ");
 		fflush(stdout);
-		vol->create_mesh(mesh, thres);
+		vol->create_mesh(mesh, thres, thres2, vol_res[0], vol_res[1], vol_res[2]);
 		printf("done.\n");
 	}
 	mesh->draw();
@@ -210,7 +230,7 @@
 
 static int prev_x, prev_y;
 static bool bn_state[32];
-static float prev_thres;
+static float prev_thres, prev_thres2;
 
 static void mouse(int bn, int state, int x, int y)
 {
@@ -221,9 +241,10 @@
 
 	if(state == GLUT_DOWN) {
 		prev_thres = thres;
+		prev_thres2 = thres2;
 	}
 	else {
-		if(thres != prev_thres) {
+		if(thres != prev_thres || thres2 != prev_thres2) {
 			mesh->clear();
 		}
 	}
diff -r c5af275b6a60 -r 1272e3335608 src/volume.cc
--- a/src/volume.cc	Mon Jan 27 01:22:02 2014 +0200
+++ b/src/volume.cc	Sun Feb 02 02:18:08 2014 +0200
@@ -168,6 +168,16 @@
 
 static Mesh *cur_mesh;
 static Volume *cur_vol;
+static float low_thres, high_thres;
+
+static float smoothstep(float x, float low, float high)
+{
+	if(x < low) return 0.0;
+	if(x >= high) return 1.0;
+
+	x = (x - low) / (high - low);
+	return x * x * (3.0 - 2.0 * x);
+}
 
 static float cb_eval(float x, float y, float z)
 {
@@ -177,7 +187,9 @@
 	int px = (x + 1) / 2.0 * img->get_width();
 	int py = (y + 1) / 2.0 * img->get_height();
 
-	return pixels[px + img->get_width() * py];
+	float val = pixels[px + img->get_width() * py];
+	float dt = 0.25 * (high_thres - low_thres);
+	return smoothstep(val, low_thres - dt, low_thres + dt) * (1 - smoothstep(val, high_thres - dt, high_thres + dt));
 }
 
 static void cb_vertex(float x, float y, float z)
@@ -193,14 +205,28 @@
 	cur_mesh->add_vertex(Vector3(x, y, z));
 }
 
-void Volume::create_mesh(Mesh *mesh, float threshold)
+void Volume::create_mesh(Mesh *mesh, float tmin, float tmax, int xres, int yres, int zres)
 {
+	if (tmin > tmax) {
+		float t = tmax;
+		tmax = tmin;
+		tmin = t;
+	}
+	low_thres = tmin; high_thres = tmax;
+
+	if(xres <= 0)
+		xres = width;
+	if(yres <= 0)
+		yres = height;
+	if(zres <= 0)
+		zres = slices.size();
+
 	cur_mesh = mesh;
 	cur_vol = this;
 
 	metasurface *ms = msurf_create();
-	msurf_threshold(ms, threshold);
-	msurf_resolution(ms, width, height, slices.size());
+	msurf_threshold(ms, 0.5);
+	msurf_resolution(ms, xres, yres, zres);
 	msurf_vertex_func(ms, cb_vertex);
 	msurf_eval_func(ms, cb_eval);
 	msurf_polygonize(ms);
diff -r c5af275b6a60 -r 1272e3335608 src/volume.h
--- a/src/volume.h	Mon Jan 27 01:22:02 2014 +0200
+++ b/src/volume.h	Sun Feb 02 02:18:08 2014 +0200
@@ -38,7 +38,7 @@
 
 	unsigned int get_texture() const;
 
-	void create_mesh(Mesh *mesh, float threshold);
+	void create_mesh(Mesh *mesh, float tmin, float tmax, int xres, int yres, int zres);
 
 	void draw() const;
 };