#include "physics.qh"
#include "input.qh"
+#if XONOTIC
.int disableclientprediction;
void sys_phys_simulate(entity this, float dt);
{
sys_phys_simulate_simple(this, frametime);
}
+
+#else
+const int PHYSICS_TRACE_PLANE_MAX = 5;
+
+// NOTE: currently unsuitable for players
+void sys_phys_update(entity this, float dt)
+{
+ // x: { 60: 0.5, 45: ~0.7, 30: ~0.9 }, from: 'vec2(0, 1) * vec2(cos(90 - x), sin(90 - x))'
+ // read as 'within x degrees'
+ float maxgrounddot = 0.5;
+ float maxstepdot = 0.7;
+ vector upvec = '0 0 1';
+ float groundsnap = 1;
+ bool jump = this.com_in_jump;
+ bool jumpstep = true;
+
+ vector mn = this.mins;
+ vector mx = this.maxs;
+
+ vector acc = this.com_phys_acc;
+ vector vel = this.com_phys_vel;
+ vector pos = this.com_phys_pos_prev = this.com_phys_pos;
+ bool onground = this.com_phys_ground;
+
+ bool nogravityonground = this.com_phys_nogravityonground;
+ float stepheight = this.com_phys_stepheight;
+ float stepdownheight = -stepheight;
+ float jumpvel = this.com_phys_jumpvel;
+ float bounce = this.com_phys_bounce;
+ float friction = this.com_phys_friction;
+ float gravity = this.com_phys_gravity.z;
+ bool noclip = this.com_phys_noclip;
+ if (noclip)
+ {
+ jump = false;
+ nogravityonground = false;
+ }
+
+ vector g = upvec * -gravity;
+
+ // apply accelaration in two steps: https://www.niksula.hut.fi/~hkankaan/Homepages/gravity.html
+ // alternatives: rk4, verlet, euler
+ vel += (acc + g) * dt / 2;
+ {
+ if (onground || noclip)
+ {
+ if (nogravityonground)
+ {
+ g = '0 0 0';
+ if (vel * upvec < 0) vel = vec_reflect(vel, upvec, 0); // kill downward velocity
+ }
+ if (jump)
+ {
+ vel += upvec * jumpvel;
+ }
+ else // the first landing frame is free
+ {
+ // friction
+ vector slide = noclip ? vel : vec_reflect(vel, upvec, 0);
+ vector push = vel - slide;
+ // TODO: slick
+ slide *= 1 - friction * dt;
+ vel = slide + push;
+ }
+ }
+ vector step = vel * dt;
+ bool pass = false;
+ bool foundground = false; // assume until proven otherwise
+ if (nogravityonground) foundground = true; // override
+ bool steplimit = 1;
+ if (noclip)
+ {
+ pass = true;
+ }
+ else
+ {
+ for (int i = 0; i < PHYSICS_TRACE_PLANE_MAX; ++i)
+ {
+ vector p0 = pos;
+ vector p1 = p0 + step;
+ tracebox(p0, mn, mx, p1, MOVE_NORMAL, this);
+ float frac = trace_fraction;
+ vector norm = trace_plane_normal;
+ if (frac == 1)
+ {
+ // all clear
+ if (steplimit > 0 && onground && vel * upvec <= 0)
+ {
+ // can we step down?
+ tracebox(p1, mn, mx, p1 + upvec * stepdownheight, MOVE_NORMAL, this);
+ if (trace_fraction == 1)
+ {
+ // no stairs here
+ }
+ else if (trace_plane_normal * upvec >= maxstepdot)
+ {
+ // step down
+ step += upvec * (stepdownheight * trace_fraction);
+ }
+ }
+ pass = true;
+ break;
+ }
+ // hit something
+ if (norm * upvec >= maxgrounddot) foundground = true;
+ if (steplimit > 0 && (jumpstep || onground)) // try: vel * upvec >= 0
+ {
+ // can we step up?
+ vector slide = vec_reflect(step, upvec, 0); // remove fall component
+ vector p1 = p0 + slide; // step is here
+ tracebox(p1 + upvec * stepheight, mn, mx, p1, MOVE_NORMAL, this);
+ if (trace_fraction < 1 && trace_plane_normal * upvec >= maxstepdot)
+ {
+ // there is a step in front of us, get above it
+ // TODO: not if it's slippery (slick)
+ vector stepup = upvec * (1 - trace_fraction) * stepheight;
+ tracebox(p0, mn, mx, p0 + stepup, MOVE_NORMAL, this);
+ if (trace_fraction == 1)
+ {
+ // go over
+ tracebox(p0 + stepup, mn, mx, p1 + stepup, MOVE_NORMAL, this);
+ if (trace_fraction == 1)
+ {
+ // all clear
+ steplimit -= 1;
+ pos += stepup;
+ if (vel * upvec < 0) vel = vec_reflect(vel, upvec, 0); // kill downward velocity
+ step = p1 - p0;
+ pass = true;
+ break;
+ }
+ }
+ }
+ }
+ // no stairs here
+ pos += frac * step;
+ vel = vec_reflect(vel, norm, bounce);
+ step = (1 - frac) * vel * dt;
+ continue;
+ }
+ }
+ if (nogravityonground)
+ {
+ vector p1 = pos + step;
+ tracebox(p1, mn, mx, p1 - groundsnap * upvec, MOVE_NORMAL, this);
+ foundground = trace_plane_normal * upvec >= maxgrounddot;
+ }
+ if (pass)
+ {
+ pos += step;
+ if (!foundground)
+ {
+ if (onground) emit(phys_stepfall, this);
+ }
+ else
+ {
+ if (!onground) emit(phys_stepland, this);
+ }
+ onground = foundground;
+ }
+ }
+ vel += (acc + g) * dt / 2;
+
+ this.com_phys_acc = acc;
+ this.com_phys_vel = vel;
+ this.com_phys_pos = pos;
+ this.com_phys_ground = onground;
+}
+#endif
projects / xonotic / xonotic-data.pk3dir.git / blobdiff