nuclear@12: /*
nuclear@12: glviewvol is an OpenGL 3D volume data viewer
nuclear@12: Copyright (C) 2014  John Tsiombikas <nuclear@member.fsf.org>
nuclear@12: 
nuclear@12: This program is free software: you can redistribute it and/or modify
nuclear@12: it under the terms of the GNU General Public License as published by
nuclear@12: the Free Software Foundation, either version 3 of the License, or
nuclear@12: (at your option) any later version.
nuclear@12: 
nuclear@12: This program is distributed in the hope that it will be useful,
nuclear@12: but WITHOUT ANY WARRANTY; without even the implied warranty of
nuclear@12: MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
nuclear@12: GNU General Public License for more details.
nuclear@12: 
nuclear@12: You should have received a copy of the GNU General Public License
nuclear@12: along with this program.  If not, see <http://www.gnu.org/licenses/>.
nuclear@12: */
nuclear@4: #include <stdio.h>
nuclear@7: #include <math.h>
nuclear@4: #include "opengl.h"
nuclear@4: #include "xfer_view.h"
nuclear@11: #include "viewer.h"
nuclear@14: #include "volume.h"
nuclear@14: 
nuclear@14: static void draw_histogram();
nuclear@4: 
nuclear@6: static TransferFunc *xfer;
nuclear@14: static Volume *vol;
nuclear@4: 
nuclear@7: static int act_color = -1;
nuclear@7: static int grabbed_handle = -1;
nuclear@7: static int mousex, mousey;
nuclear@4: 
nuclear@6: bool xfview_init(TransferFunc *xferarg)
nuclear@4: {
nuclear@6: 	xfer = xferarg;
nuclear@4: 	return true;
nuclear@4: }
nuclear@4: 
nuclear@4: void xfview_destroy()
nuclear@4: {
nuclear@4: }
nuclear@4: 
nuclear@14: void xfview_set_volume(Volume *volarg)
nuclear@14: {
nuclear@14: 	vol = volarg;
nuclear@14: }
nuclear@14: 
nuclear@4: void xfview_draw()
nuclear@4: {
nuclear@4: 	float line_color[][3] = {
nuclear@4: 		{ 1, 0, 0 }, { 0, 1, 0 }, { 0, 0, 1 }, { 1, 1, 1 }
nuclear@4: 	};
nuclear@4: 
nuclear@4: 	glMatrixMode(GL_PROJECTION);
nuclear@4: 	glLoadIdentity();
nuclear@7: 	glOrtho(0, 1, 0, 1, -1, 1);
nuclear@7: 
nuclear@4: 	glMatrixMode(GL_MODELVIEW);
nuclear@4: 	glLoadIdentity();
nuclear@4: 
nuclear@4: 	int xsz, ysz;
nuclear@4: 	get_window_size(&xsz, &ysz);
nuclear@4: 	int nsamples = xsz / 4;
nuclear@4: 
nuclear@4: 	// paint the background a faint version of the selected color
nuclear@4: 	glBegin(GL_QUADS);
nuclear@7: 	int cidx = act_color == -1 ? 3 : act_color;
nuclear@7: 	glColor3f(line_color[cidx][0] * 0.1, line_color[cidx][1] * 0.1, line_color[cidx][2] * 0.1);
nuclear@4: 	glVertex2f(-1, -1);
nuclear@4: 	glVertex2f(1, -1);
nuclear@4: 	glVertex2f(1, 1);
nuclear@4: 	glVertex2f(-1, 1);
nuclear@4: 	glEnd();
nuclear@4: 
nuclear@14: 	draw_histogram();
nuclear@14: 
nuclear@4: 	glEnable(GL_LINE_SMOOTH);
nuclear@4: 
nuclear@4: 	glEnable(GL_BLEND);
nuclear@4: 	glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
nuclear@4: 
nuclear@7: 	// draw handles on the selected curve
nuclear@7: 	TransferWindow *xfwin = dynamic_cast<TransferWindow*>(xfer);
nuclear@7: 	if(xfwin) {
nuclear@7: 		float dx = 1.0 / (float)xsz;
nuclear@7: 		float cursor = (float)mousex / (float)xsz;
nuclear@7: 		float low[3], high[3];
nuclear@7: 		xfwin->get_interval_rgba(low, high);
nuclear@7: 
nuclear@7: 		if(act_color == -1) {	// all curves
nuclear@7: 			int nearest = xfwin->nearest_handle(-1, cursor);
nuclear@7: 
nuclear@7: 			if(grabbed_handle != -1) {
nuclear@7: 				glBegin(GL_LINES);
nuclear@7: 				glColor3f(0.8, 0.8, 0.8);
nuclear@7: 				for(int i=0; i<3; i++) {
nuclear@7: 					float x = xfwin->get_handle(i, nearest);
nuclear@7: 					float rad = xfwin->get_soft_radius();
nuclear@7: 					glVertex2f(x - rad, 0.5);
nuclear@7: 					glVertex2f(x + rad, 0.5);
nuclear@7: 					glVertex2f(x - rad, 0.4);
nuclear@7: 					glVertex2f(x - rad, 0.6);
nuclear@7: 					glVertex2f(x + rad, 0.4);
nuclear@7: 					glVertex2f(x + rad, 0.6);
nuclear@7: 				}
nuclear@7: 				glEnd();
nuclear@7: 			}
nuclear@7: 
nuclear@7: 			// draw handles on all lines, highlighting the nearest side of all of them
nuclear@7: 			glBegin(GL_QUADS);
nuclear@7: 			glColor3f(1, 1, 1);
nuclear@7: 
nuclear@7: 			for(int i=0; i<3; i++) {
nuclear@7: 				float x = nearest == TransferWindow::HANDLE_LOW ? low[i] : high[i];
nuclear@7: 				glVertex2f(x - 2.0 * dx, -1);
nuclear@7: 				glVertex2f(x + 2.0 * dx, -1);
nuclear@7: 				glVertex2f(x + 2.0 * dx, 1);
nuclear@7: 				glVertex2f(x - 2.0 * dx, 1);
nuclear@7: 			}
nuclear@7: 			for(int i=0; i<3; i++) {
nuclear@7: 				glColor3fv(line_color[i]);
nuclear@7: 				glVertex2f(low[i] - dx, -1);
nuclear@7: 				glVertex2f(low[i] + dx, -1);
nuclear@7: 				glVertex2f(low[i] + dx, 1);
nuclear@7: 				glVertex2f(low[i] - dx, 1);
nuclear@7: 				glVertex2f(high[i] - dx, -1);
nuclear@7: 				glVertex2f(high[i] + dx, -1);
nuclear@7: 				glVertex2f(high[i] + dx, 1);
nuclear@7: 				glVertex2f(high[i] - dx, 1);
nuclear@7: 			}
nuclear@7: 			glEnd();
nuclear@7: 
nuclear@7: 		} else {
nuclear@7: 			int nearest = xfwin->nearest_handle(act_color, cursor);
nuclear@7: 			float x = nearest == TransferWindow::HANDLE_LOW ? low[act_color] : high[act_color];
nuclear@7: 
nuclear@7: 			if(grabbed_handle != -1) {
nuclear@7: 				float x = xfwin->get_handle(act_color, nearest);
nuclear@7: 				float rad = xfwin->get_soft_radius();
nuclear@7: 
nuclear@7: 				glBegin(GL_LINES);
nuclear@7: 				glColor3f(0.8, 0.8, 0.8);
nuclear@7: 				glVertex2f(x - rad, 0.5);
nuclear@7: 				glVertex2f(x + rad, 0.5);
nuclear@7: 				glVertex2f(x - rad, 0.4);
nuclear@7: 				glVertex2f(x - rad, 0.6);
nuclear@7: 				glVertex2f(x + rad, 0.4);
nuclear@7: 				glVertex2f(x + rad, 0.6);
nuclear@7: 				glEnd();
nuclear@7: 			}
nuclear@7: 
nuclear@7: 
nuclear@7: 			glBegin(GL_QUADS);
nuclear@7: 			glColor3f(1, 1, 1);
nuclear@7: 			glVertex2f(x - 2.0 * dx, -1);
nuclear@7: 			glVertex2f(x + 2.0 * dx, -1);
nuclear@7: 			glVertex2f(x + 2.0 * dx, 1);
nuclear@7: 			glVertex2f(x - 2.0 * dx, 1);
nuclear@7: 
nuclear@7: 			glColor3fv(line_color[act_color]);
nuclear@7: 			for(int i=0; i<2; i++) {
nuclear@7: 				glVertex2f(x - dx, -1);
nuclear@7: 				glVertex2f(x + dx, -1);
nuclear@7: 				glVertex2f(x + dx, 1);
nuclear@7: 				glVertex2f(x - dx, 1);
nuclear@7: 				x = nearest == TransferWindow::HANDLE_LOW ? high[act_color] : low[act_color];
nuclear@7: 			}
nuclear@7: 			glEnd();
nuclear@7: 		}
nuclear@7: 	}
nuclear@7: 
nuclear@6: 	// draw curve
nuclear@4: 	glLineWidth(2.0);
nuclear@4: 
nuclear@7: 	for(int i=0; i<4; i++) {
nuclear@4: 		int idx;
nuclear@7: 		if(act_color == -1) {
nuclear@7: 			idx = i;
nuclear@4: 		} else {
nuclear@7: 			idx = (i + act_color + 1) % 4;
nuclear@4: 		}
nuclear@4: 
nuclear@4: 		glColor3fv(line_color[idx]);
nuclear@4: 
nuclear@4: 		glBegin(GL_LINE_STRIP);
nuclear@4: 		for(int j=0; j<nsamples; j++) {
nuclear@4: 			float t = (float)j / (float)(nsamples - 1);
nuclear@6: 			float vval[4];
nuclear@4: 
nuclear@7: 			if(idx < 3) {
nuclear@7: 				xfer->map(t, vval);
nuclear@7: 			} else {
nuclear@7: 				vval[3] = xfer->map(t);
nuclear@7: 			}
nuclear@7: 
nuclear@7: 			glVertex2f(t, vval[idx]);
nuclear@4: 		}
nuclear@4: 		glEnd();
nuclear@4: 	}
nuclear@4: 
nuclear@4: 	glDisable(GL_BLEND);
nuclear@4: }
nuclear@4: 
nuclear@14: #define HIST_SAMPLES	256
nuclear@14: 
nuclear@14: static void draw_histogram()
nuclear@14: {
nuclear@14: 	VoxelVolume *voxvol = dynamic_cast<VoxelVolume*>(vol);
nuclear@14: 	if(!voxvol) return;
nuclear@14: 
nuclear@14: 	float *hist = voxvol->calc_histogram(HIST_SAMPLES);
nuclear@14: 	if(!hist) return;
nuclear@14: 
nuclear@14: 	float max_y = 0.0f;
nuclear@14: 	for(int i=0; i<HIST_SAMPLES; i++) {
nuclear@14: 		if(hist[i] > max_y) {
nuclear@14: 			max_y = hist[i];
nuclear@14: 		}
nuclear@14: 	}
nuclear@14: 
nuclear@14: 	float dx = 1.0 / (float)HIST_SAMPLES;
nuclear@14: 	glBegin(GL_QUADS);
nuclear@14: 	glColor3f(0.6, 0.6, 0.6);
nuclear@14: 	for(int i=0; i<HIST_SAMPLES; i++) {
nuclear@14: 		float x0 = (float)i / (float)HIST_SAMPLES;
nuclear@14: 		float x1 = x0 + dx;
nuclear@14: 
nuclear@14: 		float y = hist[i] / max_y;
nuclear@14: 
nuclear@14: 		glVertex2f(x0, 0);
nuclear@14: 		glVertex2f(x1, 0);
nuclear@14: 		glVertex2f(x1, y);
nuclear@14: 		glVertex2f(x0, y);
nuclear@14: 	}
nuclear@14: 	glEnd();
nuclear@14: }
nuclear@14: 
nuclear@7: static int prev_x, prev_y;
nuclear@7: 
nuclear@4: void xfview_button(int bn, int press, int x, int y)
nuclear@4: {
nuclear@7: 	prev_x = x;
nuclear@7: 	prev_y = y;
nuclear@7: 
nuclear@7: 	if(bn == 2 && press && grabbed_handle == -1) {
nuclear@7: 		act_color = (act_color + 2) % 4 - 1;
nuclear@4: 		redisplay();
nuclear@4: 		return;
nuclear@4: 	}
nuclear@4: 
nuclear@7: 	if(bn == 0) {
nuclear@7: 		int xsz, ysz;
nuclear@7: 		get_window_size(&xsz, &ysz);
nuclear@7: 
nuclear@7: 		TransferWindow *xfwin = dynamic_cast<TransferWindow*>(xfer);
nuclear@7: 		if(xfwin && press) {
nuclear@7: 			float cursor = (float)x / (float)xsz;
nuclear@7: 			float low[3], high[3];
nuclear@7: 			xfwin->get_interval_rgba(low, high);
nuclear@7: 
nuclear@7: 			// grab the nearest handle
nuclear@7: 			grabbed_handle = xfwin->nearest_handle(act_color, cursor);
nuclear@5: 		} else {
nuclear@7: 			grabbed_handle = -1;
nuclear@5: 		}
nuclear@7: 		redisplay();
nuclear@4: 	}
nuclear@4: }
nuclear@4: 
nuclear@4: void xfview_motion(int x, int y)
nuclear@4: {
nuclear@7: 	mousex = x;
nuclear@7: 	mousey = y;
nuclear@7: 
nuclear@7: 	int dx = x - prev_x;
nuclear@7: 	int dy = y - prev_y;
nuclear@7: 	prev_x = x;
nuclear@7: 	prev_y = y;
nuclear@7: 
nuclear@7: 	if(grabbed_handle != -1) {
nuclear@7: 		TransferWindow *xfwin = dynamic_cast<TransferWindow*>(xfer);
nuclear@7: 		if(!xfwin) return;
nuclear@7: 
nuclear@7: 		int xsz, ysz;
nuclear@7: 		get_window_size(&xsz, &ysz);
nuclear@7: 
nuclear@7: 		if(get_modifiers()) {
nuclear@7: 			float soft = xfwin->get_soft_radius() + dy * 0.01;
nuclear@7: 			if(soft < 0.0) soft = 0.0;
nuclear@7: 			xfwin->set_soft_radius(soft);
nuclear@7: 		} else {
nuclear@7: 			float pos = (float)x / (float)xsz;
nuclear@7: 			xfwin->set_handle(act_color, grabbed_handle, pos);
nuclear@7: 		}
nuclear@7: 	}
nuclear@7: 
nuclear@7: 	redisplay();
nuclear@4: }