Page MenuHome
Differential D6807 Diff 21591 source/blender/editors/curve/poly_demo.cpp

Changeset View

Standalone View

View Options

source/blender/editors/curve/poly_demo.cpp

  • This file was added.
#include <GLUT/glut.h>
#include <cstdio>
#include <cstring>
#include <cmath>
#include <vector>
bool debug = true;
float intersect_check_tol = .001; //Maximum Euclidean dist between intersect pts
// GLUT coords. Format: (x,y)
// (1,1)(w,1) |----->
// |
// (1,h)(w,h) v
// GL coords. Format: (x,y) Specified via gluOrtho2D
// (-1,1) (1,1) ^
// |
// (-1,-1) (1,-1) |------>
/***************************** MATH *****************************/
#include "poly.h"
/***************************** DEFAULT SCENE *****************************/
bool clip_cyclic = true; // Required for initialization
std::vector<float> clip_verts = {-0.460000,-0.004000, 0.360000,-0.072000, 0.388000,-0.744000, -0.440000,-0.720000};
bool subj_cyclic = true;
std::vector<float> subj0 = {-0.500000,-0.500000, 0.500000,-0.500000};
std::vector<float> subj1 = {-0.500000,-0.000000, 0.500000,-0.000000};
std::vector<std::vector<float>> subj_polys = {subj0,subj1};
std::vector<float> inout_pts;
GreinerV2f *clip = nullptr;
GreinerV2f *subj = nullptr; // Uses the linked list param nextPoly!
int win_width = 500;
int win_height = 500;
void glut_coords_2_scene(float gx, float gy, float* sx, float* sy) {
gx /= win_width;
gy /= win_height;
*sx = 2*gx-1;
*sy = 2*(1-gy)-1;
}
void init_default_scene() {
// Import the clip polygon into the linked-list datastructure
GreinerV2f *last = nullptr;
size_t clip_n = clip_verts.size()/2;
for (int i=0; i<clip_n; i++) {
GreinerV2f *v = new GreinerV2f();
v->x = clip_verts[2*i+0];
v->y = clip_verts[2*i+1];
v->prev = last;
if (last) last->next = v;
else clip = v;
last = v;
}
if (clip_cyclic) {
clip->prev = last;
last->next = clip;
}
clip->isBackbone = true;
// Import the subject polygons into the linked list datastructure
last = nullptr;
for (std::vector<float> poly_verts : subj_polys) {
// Different subject polygons are stored in
// subj, subj->nextPoly, subj->nextPoly->nextPoly etc
GreinerV2f *newpoly_first_vert = new GreinerV2f();
newpoly_first_vert -> isBackbone = true;
if (!subj) {
subj = newpoly_first_vert;
} else {
last->nextPoly = newpoly_first_vert;
}
last = newpoly_first_vert;
// Fill in the vertices of the polygon we just finished hooking up
// to the polygon list
GreinerV2f *last_inner = nullptr;
for (size_t i=0,l=poly_verts.size()/2; i<l; i++) {
GreinerV2f *v;
if (i==0) {
v = newpoly_first_vert;
} else {
v = new GreinerV2f();
}
v->x = poly_verts[2*i+0];
v->y = poly_verts[2*i+1];
v->prev = last_inner;
if (last_inner) last_inner->next = v;
last_inner = v;
}
if (subj_cyclic) {
newpoly_first_vert->prev = last_inner;
last_inner->next = newpoly_first_vert;
}
}
}
void GLUT_init(){
glClearColor(0,0,0,0);
glMatrixMode(GL_PROJECTION);
// Defines the view box
// left,right,bottom,top
gluOrtho2D(-1,1,-1,1);
init_default_scene();
}
/***************************** DRAW *****************************/
GreinerV2f *intersect_pt = nullptr;
void GLUT_display(){
glClear(GL_COLOR_BUFFER_BIT);
// Draw Clip polygon lines
glBegin(GL_LINES);
float last_x=clip->x, last_y=clip->y;
bool is_outside = true;
if (subj_cyclic) is_outside = point_in_polygon(last_x, last_y, clip);
for (GreinerV2f *v=clip->next; v; v=v->next) {
float x=v->x, y=v->y;
if (is_outside) glColor3f(.8,0,0);
else glColor3f(1,.6,.6);
glVertex2f(last_x,last_y);
glVertex2f(x,y);
last_x=x; last_y=y;
if (v==clip) break;
if (v->isIntersection) is_outside = !is_outside;
}
glEnd();
//Draw Clip polygon verts
glPointSize(5);
glBegin(GL_POINTS);
glColor3f(1,0,0);
bool first_iter = true;
for (GreinerV2f *v=clip; v; v=v->next) {
glVertex2f(v->x,v->y);
if (!first_iter && v==clip) break;
first_iter = false;
}
glEnd();
// Draw Subject polygon lines
glBegin(GL_LINES);
for (GreinerV2f *curpoly=subj; curpoly; curpoly=curpoly->nextPoly) {
is_outside = true;
last_x=curpoly->x, last_y=curpoly->y;
if (clip_cyclic) is_outside = point_in_polygon(last_x, last_y, curpoly);
for (GreinerV2f *v=curpoly->next; v; v=v->next) {
float x=v->x, y=v->y;
if (is_outside) glColor3f(0,.8,0);
else glColor3f(.8,1,.8);
glVertex2f(last_x,last_y);
glVertex2f(x,y);
last_x=x; last_y=y;
if (v==curpoly) break;
if (v->isIntersection) is_outside = !is_outside;
}
}
glEnd();
// Draw Subject polygon verts
glPointSize(3);
glBegin(GL_POINTS);
glColor3f(0,1,0);
for (GreinerV2f *curpoly=subj; curpoly; curpoly=curpoly->nextPoly) {
last_x=curpoly->x, last_y=curpoly->y;
for (GreinerV2f *v=curpoly; v; v=v->next) {
float x=v->x, y=v->y;
if (!v->isBackbone) glColor3f(0,.8,0);
else glColor3f(1,1,0);
glVertex2f(x,y);
last_x=x; last_y=y;
if (v->next==curpoly) break;
if (v->isIntersection) is_outside = !is_outside;
}
}
glEnd();
// Draw intersection point
if (intersect_pt) {
glPointSize(5);
glBegin(GL_POINTS);
glColor3f(1,1,0);
glVertex2f(intersect_pt->x, intersect_pt->y);
glEnd();
}
// Draw inclusion/exclusion test points
if (clip_cyclic) {
glPointSize(5);
glBegin(GL_POINTS);
for (size_t i=0,l=inout_pts.size()/2; i<l; i++) {
float x=inout_pts[i*2+0], y=inout_pts[i*2+1];
bool pip = point_in_polygon(x,y,clip);
if (pip) glColor3f(1,1,0);
else glColor3f(0, 0, 1);
glVertex2f(x,y);
}
glEnd();
}
glFlush();
}
/***************************** INTERACTION *****************************/
GreinerV2f *grabbed_vert = nullptr;
void GLUT_reshape(int w, int h){
glViewport(0,0,w,h);
win_width = w;
win_height = h;
if (debug){
printf("GLUT_reshape w:%d h:%d\n",w,h);
}
}
void dump_polys_to_stdout() {
printf("bool clip_cyclic = %s; // Required for initialization\n",clip_cyclic?"true":"false");
printf("bool subj_cyclic = %s;\n",subj_cyclic?"true":"false");
printf("std::vector<float> clip_verts = {");
for (GreinerV2f *v=clip; v; v=v->next) {
printf((v->next&&v->next!=clip)?"%f,%f, ":"%f,%f};\n",v->x,v->y);
if (v->next==clip) break;
}
int subj_poly_num = 0;
for (GreinerV2f *subj_poly=subj; subj_poly; subj_poly=subj->nextPoly) {
printf("std::vector<float> subj%i = {", subj_poly_num);
for (GreinerV2f *v=subj_poly; v; v=v->next) {
printf((v->next&&v->next!=subj)?"%f,%f, ":"%f,%f};\n",v->x,v->y);
if (v->next==subj_poly || v->next->isBackbone) break;
}
subj_poly_num++;
}
printf("std::vector<std::vector<float>> subj_polys = {");
for (int i=0; i<subj_poly_num; i++) {
printf((i!=subj_poly_num-1)?"subj%i,":"subj%i};\n",i);
}
printf("std::vector<float> inout_pts = {");
for (size_t i=0,l=inout_pts.size()/2; i<l; i++) {
printf((i!=l-1)?"%f,%f, ":"%f,%f};\n",inout_pts[2*i+0],inout_pts[2*i+1]);
}
}
void toggle_cyclic(GreinerV2f *curve) {
GreinerV2f *backbone = curve;
while (!backbone->isBackbone) backbone=backbone->prev;
if (backbone==clip) {
if (clip_cyclic) {
clip->prev->next = nullptr;
clip->prev = nullptr;
clip_cyclic = false;
} else {
GreinerV2f *last = clip;
while (last->next) last = last->next;
last->next = clip;
clip->prev = last;
clip_cyclic = true;
}
} else { // Backbone is one of subj polys
for (GreinerV2f *poly=subj; poly; poly=poly->nextPoly) {
if (subj_cyclic) {
if (poly->prev) poly->prev->next = nullptr;
poly->prev = nullptr;
} else {
GreinerV2f *last = poly;
while (last->next) {
if (last->next && last->next->isBackbone) break;
last = last->next;
}
last->next = poly;
poly->prev = last;
}
}
subj_cyclic = !subj_cyclic;
}
glutPostRedisplay();
}
void delete_last_selected_vert() {
// Don't allow #subj verts or #clip verts -> 0
if (!grabbed_vert || grabbed_vert==clip) return;
if (grabbed_vert==subj) {
if (grabbed_vert->nextPoly) {
subj = grabbed_vert->nextPoly;
delete grabbed_vert;
glutPostRedisplay();
return;
}
else return;
}
// Did we grab a vert along the subject polygon backbone?
for (GreinerV2f *v = subj; v->nextPoly; v=v->nextPoly) {
if (grabbed_vert==v->nextPoly) {
v->nextPoly = grabbed_vert->nextPoly;
delete grabbed_vert;
glutPostRedisplay();
return;
}
}
// Otherwise we just have to worry about the doubly-linked-list of intra-polygon
// verts
GreinerV2f *next=grabbed_vert->next, *prev=grabbed_vert->prev;
if (next && prev) {
prev->next = next;
next->prev = prev;
} else if (next) {
next->prev = nullptr;
} else if (prev) {
prev->next = nullptr;
}
delete grabbed_vert;
grabbed_vert = nullptr;
glutPostRedisplay();
}
#define GLUT_KEY_ESC 27
#define GLUT_KEY_RETURN 13
#define GLUT_KEY_DELETE 127
void GLUT_keyboard(unsigned char ch, int x, int y ) {
int m = glutGetModifiers();
if (debug) {
char m_str[128]; m_str[0]=0;
if (m&GLUT_ACTIVE_ALT) strcpy(m_str+strlen(m_str),"ALT,");
if (m&GLUT_ACTIVE_SHIFT) strcpy(m_str+strlen(m_str),"SHIFT,");
if (m&GLUT_ACTIVE_CTRL) strcpy(m_str+strlen(m_str),"CTRL,");
printf("GLUT_keyboard x:%d y:%d ch:%i mod:%x(%s)\n",x,y,(int)ch,m,m_str);
}
if (ch==GLUT_KEY_ESC) {
init_default_scene();
glutPostRedisplay();
}
if (ch==GLUT_KEY_RETURN) {
dump_polys_to_stdout();
}
if (ch=='i') {
add_verts_at_intersections(clip,subj);
glutPostRedisplay();
}
if (ch=='1') toggle_cyclic(clip);
if (ch=='2') toggle_cyclic(subj);
if (ch==GLUT_KEY_DELETE) delete_last_selected_vert();
}
void GLUT_specialkey(int ch, int x, int y) {
// CTRL, SHIFT, arrows actually work
// alt/option, command do not
if (debug) {
const char* ch_str = "???";
if (ch==GLUT_KEY_LEFT) ch_str = "GLUT_KEY_LEFT";
if (ch==GLUT_KEY_RIGHT) ch_str = "GLUT_KEY_RIGHT";
if (ch==GLUT_KEY_UP) ch_str = "GLUT_KEY_UP";
if (ch==GLUT_KEY_DOWN) ch_str = "GLUT_KEY_DOWN";
printf("GLUT_specialkey x:%d y:%d ch:%x(%s)\n",x,y,ch,ch_str);
}
}
void create_new_poly(float sx, float sy) {
GreinerV2f *last_backbone = subj;
while (last_backbone->nextPoly) last_backbone = last_backbone->nextPoly;
GreinerV2f *newpoly = new GreinerV2f();
newpoly->x = sx; newpoly->y = sy;
last_backbone->nextPoly = newpoly;
glutPostRedisplay();
}
void create_pt(float sx, float sy) {
if (!grabbed_vert) return;
GreinerV2f *last_vert = grabbed_vert;
while (last_vert->next && !last_vert->isBackbone)
last_vert = last_vert->next;
GreinerV2f *v = new GreinerV2f();
v->x = sx;
v->y = sy;
if (last_vert->next) { // is cyclic
GreinerV2f *first_vert = last_vert->next;
last_vert->next = v;
v->prev = last_vert;
first_vert->prev = v;
v->next = first_vert;
} else {
last_vert->next = v;
v->prev = last_vert;
}
grabbed_vert = v; // Let's drag the new vert we just made
glutPostRedisplay();
}
void initiate_pt_drag_if_near_pt(float sx, float sy) {
float closest_dist = 1e50;
GreinerV2f *closest_vert = nullptr;
for (GreinerV2f *v=clip; v; v=v->next) {
float dx = v->x - sx;
float dy = v->y - sy;
float dist = sqrt(dx*dx + dy*dy);
if (dist<closest_dist) {
closest_dist = dist;
closest_vert = v;
}
if (v->next==clip) break;
}
for (GreinerV2f *poly=subj; poly; poly=poly->nextPoly) {
for (GreinerV2f *v=poly; v; v=v->next) {
float dx = v->x - sx;
float dy = v->y - sy;
float dist = sqrt(dx*dx + dy*dy);
if (dist<closest_dist) {
closest_dist = dist;
closest_vert = v;
}
if (v->next==poly) break;
}
}
if (debug) printf("Nearest point to mousedown (%f)\n",closest_dist);
grabbed_vert = (closest_dist<.025) ? closest_vert : nullptr;
}
void terminate_pt_drag() {
//grabbed_vert = nullptr;
}
void GLUT_mouse( int button, int state, int x, int y) {
float sx,sy;
glut_coords_2_scene(x,y,&sx,&sy);
int m = glutGetModifiers();
if (debug) {
const char* state_str = "???";
if (state==GLUT_DOWN) state_str = "GLUT_DOWN";
if (state==GLUT_UP) state_str = "GLUT_UP";
const char* button_str = "???";
if (button==GLUT_LEFT_BUTTON) button_str = "GLUT_LEFT_BUTTON";
if (button==GLUT_MIDDLE_BUTTON) button_str = "GLUT_MIDDLE_BUTTON";
if (button==GLUT_RIGHT_BUTTON) button_str = "GLUT_RIGHT_BUTTON";
printf("GLUT_mouse x:%d y:%d button:%x(%s) state:%x(%s)\n",
x,y,button,button_str,state,state_str);
}
if (state==GLUT_DOWN && button==GLUT_LEFT_BUTTON) {
if (m&GLUT_ACTIVE_CTRL && m&GLUT_ACTIVE_SHIFT)
create_new_poly(sx,sy);
else if (m&GLUT_ACTIVE_CTRL)
create_pt(sx,sy);
else
initiate_pt_drag_if_near_pt(sx,sy);
}
if (state==GLUT_DOWN && button==GLUT_RIGHT_BUTTON) {
inout_pts.push_back(sx);
inout_pts.push_back(sy);
glutPostRedisplay();
}
if (state==GLUT_UP) {
terminate_pt_drag();
}
}
void GLUT_motion(int x, int y) {
float sx,sy;
glut_coords_2_scene(x,y,&sx,&sy);
if (grabbed_vert) {
grabbed_vert->x = sx;
grabbed_vert->y = sy;
glutPostRedisplay();
}
if (clip && clip->next && subj && subj->next) {
float alpha1, alpha2;
bool does_intersect = get_line_seg_intersection(clip,clip->next,&alpha1, subj,subj->next,&alpha2);
if (does_intersect) {
if (!intersect_pt) intersect_pt = new GreinerV2f();
intersect_pt->x = (1-alpha1)*clip->x + alpha1*clip->next->x;
intersect_pt->y = (1-alpha1)*clip->y + alpha1*clip->next->y;
} else {
intersect_pt = nullptr;
}
} else {
intersect_pt = nullptr;
}
}
/***************************** MAIN *****************************/
int main(int argc, char **argv){
glutInit(& argc, argv);
glutInitDisplayMode(GLUT_SINGLE|GLUT_RGB);
glutInitWindowSize(win_width,win_height);
glutInitWindowPosition(200,200);
glutCreateWindow("Polygon Split Viz");
glutDisplayFunc(GLUT_display);
glutReshapeFunc(GLUT_reshape);
glutMouseFunc(GLUT_mouse);
glutMotionFunc(GLUT_motion); // Mouse is dragged. Callback args: (int x, int y)
glutPassiveMotionFunc(NULL); // Mouse is moved. Callback args: (int x, int y)
glutKeyboardFunc(GLUT_keyboard);
glutSpecialFunc(GLUT_specialkey);
GLUT_init();
puts("Welcome to the polygon demo! This was designed to be a convenient ");
puts("sandbox for testing polygon trim code designed as a part of blender's ");
puts(" new NURBS functionality.");
puts("------ Instructions: ------");
puts("<LMB down/drag>: move polyline/polygon vertices around");
puts("<CTRL>+<LMB>: new vertex on last touched polyline");
puts("<ENTER>: dump vertices in format suitable for copypaste into code");
puts("<ESC>: reset to default 'scene'");
puts("i: insert vertices at points of intersection between the two polylines/gons");
puts("1: toggle clip (red) polyline<->polygon");
puts("2: toggle subj (green) polyline<->polygon");
puts("---------------------------");
glutMainLoop();
return 0;
}
No newline at end of file