path: root/src/esp.cpp

// esp.cpp — ESP drawing + shared world_to_screen / entity gather (aimbot reuses these)
#include "esp_internal.h"
#include "hl2h.h"
#include <cmath>
#include <cstring>
#include <strings.h>
#include <cstddef>
#include <cstdlib>
#include <ctime>



struct EspTarget {
  int idx;
  float sx, sy;       // screen pos of feet
  float h;            // box height px
  float health, maxhealth;
  bool show_health;
  bool friendly;
  bool neutral;
  int damage; // NpcDamageClass
  int state;  // server NPC_STATE_*
  char weapon[24];
  char name[48];
};

struct ArrowTarget {
  Vector head;
  bool neutral;
};
static ArrowTarget g_arrows[32];
static int g_narrows = 0;
static EspTarget g_targets[128];
static int g_ntargets = 0;
int g_scr_w = 0, g_scr_h = 0;
static bool g_esp_logged = false;


// Speed graph: 100 samples at 0.1 s = the last 10 seconds.
static constexpr int SPEED_SAMPLES = 100;
static float g_speed_samples[SPEED_SAMPLES] = {};
static int g_speed_head = 0;
static double g_speed_last_sample = 0.0;

double esp_now() {
  timespec ts;
  clock_gettime(CLOCK_MONOTONIC, &ts);
  return (double)ts.tv_sec + (double)ts.tv_nsec * 1e-9;
}

// Refresh the cached screen size every frame. It used to be read once, so a
// resolution or window change left every projection, screen-edge clamp and
// centering calculation stale for the rest of the session.
bool esp_update_screen() {
  if (!g_surface)
    return false;
  int w = 0, h = 0;
  overlay_screen_size(w, h);
  if (w > 0)
    g_scr_w = w;
  if (h > 0)
    g_scr_h = h;
  return g_scr_w > 0 && g_scr_h > 0;
}

// Local perspective projection used when the engine's debug-overlay
// projection refuses a point that is actually in front of the camera.
static bool project_manual(const Vector &w, float &sx, float &sy) {
  if (!g_scr_w || !g_scr_h)
    return false;
  float pitch = g_cam_view.x * PI_F / 180.0f;
  float yaw = g_cam_view.y * PI_F / 180.0f;
  float roll = g_cam_view.z * PI_F / 180.0f;
  float sp = sinf(pitch), cp = cosf(pitch);
  float syy = sinf(yaw), cy = cosf(yaw);
  float sr = sinf(roll), cr = cosf(roll);
  float fwd[3] = {cp * cy, cp * syy, -sp};
  // Source's AngleVectors with roll; the old right/up vectors assumed roll 0,
  // so view punch made the fallback projection rotate against the world.
  float right[3] = {-sr * sp * cy + cr * syy, -sr * sp * syy - cr * cy,
                    -sr * cp};
  float up[3] = {cr * sp * cy + sr * syy, cr * sp * syy - sr * cy, cr * cp};
  float dx = w.x - g_cam_eye.x, dy = w.y - g_cam_eye.y, dz = w.z - g_cam_eye.z;
  float z = dx * fwd[0] + dy * fwd[1] + dz * fwd[2];
  if (z < 1.0f)
    return false;
  float x = dx * right[0] + dy * right[1] + dz * right[2];
  float y = dx * up[0] + dy * up[1] + dz * up[2];
  float fov = g_fov_camera > 10 ? (float)g_fov_camera : 75.0f;
  // Source defines the FOV for a 4:3 reference and widens it on widescreen;
  // using a raw tan(fov/2) made the fallback ~33% too narrow at 16:9.
  float aspect = (float)g_scr_w / (float)g_scr_h;
  float tanfov = tanf(fov * 0.5f * PI_F / 180.0f) * (aspect / (4.0f / 3.0f));
  sx = (float)g_scr_w * 0.5f + (x / z) * ((float)g_scr_w * 0.5f / tanfov);
  sy = (float)g_scr_h * 0.5f - (y / z) * ((float)g_scr_w * 0.5f / tanfov);
  return std::isfinite(sx) && std::isfinite(sy) && fabsf(sx) < 1e7f &&
         fabsf(sy) < 1e7f;
}

bool world_to_screen(const Vector &w, float &sx, float &sy) {
  // Preferred: the engine's own transform. Uses the real view setup (FOV,
  // aspect, roll), so boxes do not drift at the screen edges.
  if (g_iface.debugoverlay) {
    using Fn = int (*)(void *, const Vector *, Vector *);
    Vector s;
    int behind =
        vfunc<Fn>(g_iface.debugoverlay, 9)(g_iface.debugoverlay, &w, &s);
    if (behind) {
      // The overlay transform can report "behind" for points that are in
      // front but near the view axis/extremes (e.g. something directly below
      // the player). Use the local projection in that case.
      float pitch = g_cam_view.x * PI_F / 180.0f;
      float yaw = g_cam_view.y * PI_F / 180.0f;
      float cp = cosf(pitch), sp = sinf(pitch);
      float fwd[3] = {cp * cosf(yaw), cp * sinf(yaw), -sp};
      float z = (w.x - g_cam_eye.x) * fwd[0] +
                (w.y - g_cam_eye.y) * fwd[1] +
                (w.z - g_cam_eye.z) * fwd[2];
      if (z > 4.0f)
        return project_manual(w, sx, sy);
      return false;
    }
    // A point on the view axis can produce NaN/inf or enormous coordinates;
    // drawing those as ints corrupts the surface clip state and hides the
    // rest of the overlay.
    if (!std::isfinite(s.x) || !std::isfinite(s.y) || fabsf(s.x) > 1e7f ||
        fabsf(s.y) > 1e7f)
      return false;
    sx = s.x;
    sy = s.y;
    return true;
  }
  return project_manual(w, sx, sy);
}

// ---------------------------------------------------------------------------
// entity helpers (IClientEntityList / IClientNetworkable, header-documented)
// ---------------------------------------------------------------------------

using GetNetFn = void *(*)(void *, int);
using GetCCFn = void *(*)(void *);
using GetModelFn = const void *(*)(void *, int);
using GetModelNameFn = const char *(*)(void *, const void *);

// entitylist slot 0 = GetClientNetworkable(entnum). Safer than assuming the
// IClientNetworkable subobject offset inside the entity (see projectz).
static void relation_rgb(const EspTarget &t, int &r, int &g, int &b) {
  const int *c = t.friendly ? g_esp_col_friendly
                            : t.neutral ? g_esp_col_neutral
                                        : g_esp_col_hostile;
  r = c[0];
  g = c[1];
  b = c[2];
}

static void esp_collect(int local_idx) {
  // outer_draw() runs once per PaintTraverseEx call (several per frame); cache
  // the scan briefly so we do not walk the entity list dozens of times a frame.
  static double last_scan = 0.0;
  static double last_dbg = 0.0;
  double now = esp_now();
  if (now - last_scan < 0.01)
    return;
  last_scan = now;
  bool dbg = (now - last_dbg) >= 2.0;
  if (dbg) last_dbg = now;

  g_ntargets = 0;
  g_narrows = 0;
  using Fn = int (*)(void *);
  int hi = vfunc<Fn>(g_iface.entitylist, 6)(g_iface.entitylist); // GetHighestEntityIndex
  if (hi < 0 || hi > 4096) hi = 4096;
  int npc_alive = 0, dbg_lines = 0;
  bool srv = resolve_server_netvars();

  for (int idx = 1; idx <= hi && g_ntargets < 128; idx++) {
    if (idx == local_idx) continue;
    void *ent = entitylist_get(idx);
    if (!ent) continue;
    entptr_store(ent, idx);
    void *net = entity_networkable(idx);
    if (!net || entity_is_dormant(net)) continue;
    const char *cls = entity_class_name(net, nullptr);
    if (!cls) continue;

    uintptr_t e = (uintptr_t)ent;
    int cli_life = g_net.lifestate >= 0
                       ? (int)*(unsigned char *)(e + g_net.lifestate)
                       : -1;
    int cli_hp = g_net.health >= 0 ? *(int *)(e + g_net.health) : 0;
    bool npc = is_npc_class(cls);
    const char *model = entity_model_name(ent);

    // NPC health is not networked; read it from the listen-server entity.
    int hp = cli_hp, maxhp = -1, life = cli_life;
    if (npc && srv) {
      int slife = -1, smax = -1;
      void *sbase = nullptr;
      int shp = server_entity_health(idx, &smax, &slife, &sbase);
      if (!g_srv_checked && sbase) {
        int cli_mi =
            g_net.modelindex >= 0 ? *(int *)(e + g_net.modelindex) : -1;
        int srv_mi = server_model_index(sbase);
        // Wait for both indices: the client index is often 0 for a tick right
        // after a map load, which used to latch "untrusted" permanently.
        if (cli_mi > 0 && srv_mi > 0) {
          g_srv_checked = true;
          g_srv_trusted = (cli_mi == srv_mi);
          logd("ESP server check: idx=%d base=%p cli_model=%d srv_model=%d "
               "hp=%d maxhp=%d life=%d trusted=%d",
               idx, sbase, cli_mi, srv_mi, shp, smax, slife,
               (int)g_srv_trusted);
          if (!g_srv_trusted)
            logf("ESP: server entity mismatch, ignoring server values");
        }
      }
      if (g_srv_trusted) {
        if (shp >= 0) hp = shp;
        if (smax > 0) maxhp = smax;
        if (slife >= 0) life = slife;
      }
    }

    if (dbg && npc && dbg_lines < 40) {
      dbg_lines++;
      logd("ESP npc %d cls=%s life=%d(cli %d) hp=%d(cli %d) maxhp=%d model=%s",
           idx, cls, life, cli_life, hp, cli_hp, maxhp,
           model ? model : "?");
    }

    if (npc) {
      if (life != LIFE_ALIVE) continue;
      npc_alive++;
    } else {
      // players (HL2DM) are the only entities with a live networked m_iHealth
      if (!strstr(cls, "Player") || !(hp > 0)) continue;
    }

    float minz = g_net.mins >= 0 ? *(float *)(e + g_net.mins + 8) : 0.0f;
    float maxz = g_net.maxs >= 0 ? *(float *)(e + g_net.maxs + 8) : 72.0f;
    if (!(maxz > minz + 4.0f && maxz - minz < 512.0f)) {
      minz = 0.0f;
      maxz = 72.0f;
    }
    Vector origin{*(float *)(e + g_net.origin), *(float *)(e + g_net.origin + 4),
                  *(float *)(e + g_net.origin + 8)};
    bool neutral = false;
    bool friendly = npc && npc_is_friendly(idx, model, local_idx, neutral);
    // Arrows are collected before projection: a hostile behind the camera
    // never produces on-screen box coordinates.
    if (npc && g_narrows < 32 && !friendly &&
        (!neutral || esp_option(ESP_OPT_SHOW_NEUTRAL))) {
      ArrowTarget &a = g_arrows[g_narrows++];
      a.head = Vector{origin.x, origin.y, origin.z + maxz * 0.7f};
      a.neutral = neutral;
    }
    // Project several points along the vertical axis. Requiring both feet and
    // head to project dropped the target when the feet were behind the near
    // plane (common when standing over/next to something).
    float min_sy = 1e9f, max_sy = -1e9f, low_x = 0.0f;
    bool projected = false;
    const int VSAMPLES = 6;
    for (int k = 0; k <= VSAMPLES; k++) {
      float z = origin.z + minz +
                (maxz - minz) * (float)k / (float)VSAMPLES;
      float px, py;
      if (!world_to_screen(Vector{origin.x, origin.y, z}, px, py))
        continue;
      if (px < -2.0f * (float)g_scr_w || px > 3.0f * (float)g_scr_w)
        continue;
      projected = true;
      if (py < min_sy)
        min_sy = py;
      if (py > max_sy) {
        max_sy = py;
        low_x = px;
      }
    }
    if (!projected) {
      static int fail_logs = 0;
      float ddx = origin.x - g_cam_eye.x;
      float ddy = origin.y - g_cam_eye.y;
      float ddz = origin.z - g_cam_eye.z;
      if (fail_logs < 8 && ddx * ddx + ddy * ddy + ddz * ddz < 400.0f * 400.0f) {
        fail_logs++;
        logf("ESP: close target %d model=%s failed projection at "
             "(%.1f %.1f %.1f)",
             idx, model ? model : "?", origin.x, origin.y, origin.z);
      }
      continue;
    }
    float h = max_sy - min_sy;
    if (h < 3.0f || max_sy < 0 || min_sy > (float)g_scr_h)
      continue; // behind / offscreen
    if (low_x < -(float)g_scr_w || low_x > 2.0f * (float)g_scr_w)
      continue;
    float sx = low_x, sy = max_sy;

    EspTarget &t = g_targets[g_ntargets++];
    t.idx = idx;
    t.sx = sx; t.sy = sy; t.h = h;
    t.health = hp > 0 ? (float)hp : 0.0f;
    t.maxhealth = maxhp > 0 ? (float)maxhp : 100.0f;
    t.show_health = hp > 0;
    t.friendly = friendly;
    t.neutral = neutral;
    t.damage = npc_damage_class(idx, model);
    t.state = npc ? server_npc_state(idx) : -1;
    t.weapon[0] = 0;
    if (npc)
      weapon_short_name(idx, t.weapon, sizeof(t.weapon));
    short_name(model, t.name, sizeof(t.name));
    if (npc && !model) snprintf(t.name, sizeof(t.name), "NPC");
  }

  if (dbg)
    logd("ESP scan: hi=%d npc_alive=%d targets=%d", hi, npc_alive, g_ntargets);
  if (g_ntargets && !g_esp_logged) {
    g_esp_logged = true;
    logd("ESP: first targets, %d", g_ntargets);
  }
}

void surf_rect(int filled, int x0, int y0, int x1, int y1) {
  if (filled)
    overlay_fill(x0, y0, x1, y1);
  else
    overlay_outline_rect(x0, y0, x1, y1);
}
void surf_color(int r, int g, int b, int a) {
  overlay_color(r, g, b, a);
}
void surf_line(int x0, int y0, int x1, int y1) {
  overlay_line(x0, y0, x1, y1);
}

// Screen projection of the aimbot FOV cone boundary, using the engine's own
// world->screen transform so it follows the actual aspect/fov.
QAngle engine_view_angles() {
  QAngle v{g_cam_view.x, g_cam_view.y, g_cam_view.z};
  if (g_iface.engine) {
    using Fn = void (*)(void *, QAngle *);
    vfunc<Fn>(g_iface.engine, 19)(g_iface.engine, &v);
  }
  return v;
}

void esp_draw_fov_circle() {
  if (!g_surface || !aimbot_fov_circle())
    return;
  // No local player means no game world (main menu); the cached camera is stale
  // and the projected circle would land at a meaningless spot.
  if (engine_get_local_player() <= 0)
    return;
  if (!esp_update_screen())
    return;
  float fov = (float)aimbot_fov();
  if (fov < 1.0f || fov >= 89.0f) // beyond this the "circle" is behind the eye
    return;
  float alpha = fov * PI_F / 180.0f;
  QAngle view = engine_view_angles();
  float yaw = view.y * PI_F / 180.0f;
  float pitch = view.x * PI_F / 180.0f;
  Vector fwd{cosf(pitch) * cosf(yaw), cosf(pitch) * sinf(yaw), -sinf(pitch)};
  Vector right{sinf(yaw), -cosf(yaw), 0.0f};
  Vector up{right.y * fwd.z - right.z * fwd.y,
            right.z * fwd.x - right.x * fwd.z,
            right.x * fwd.y - right.y * fwd.x};

  constexpr float D = 1024.0f;
  float ca = cosf(alpha), sa = sinf(alpha);
  Vector eh{g_cam_eye.x + (fwd.x * ca + right.x * sa) * D,
            g_cam_eye.y + (fwd.y * ca + right.y * sa) * D,
            g_cam_eye.z + (fwd.z * ca + right.z * sa) * D};
  Vector ev{g_cam_eye.x + (fwd.x * ca + up.x * sa) * D,
            g_cam_eye.y + (fwd.y * ca + up.y * sa) * D,
            g_cam_eye.z + (fwd.z * ca + up.z * sa) * D};
  float hsx, hsy, vsx, vsy;
  if (!world_to_screen(eh, hsx, hsy) || !world_to_screen(ev, vsx, vsy))
    return;

  float cx = (float)g_scr_w * 0.5f, cy = (float)g_scr_h * 0.5f;
  float rx = fabsf(hsx - cx), ry = fabsf(vsy - cy);
  if (!(rx > 1.0f && ry > 1.0f) || rx > 1e5f || ry > 1e5f)
    return;

  constexpr int N = 64;
  int px = 0, py = 0;
  surf_color(255, 255, 255, 160);
  for (int i = 0; i <= N; i++) {
    float phi = (2.0f * PI_F * i) / N;
    int x = (int)(cx + rx * cosf(phi));
    int y = (int)(cy + ry * sinf(phi));
    if (i > 0)
      surf_line(px, py, x, y);
    px = x;
    py = y;
  }
}

// Speed graph: 100 samples at 0.1 s = the last 10 seconds; min is 0, max is
// the window maximum. Small and centered in the lower half of the screen.
static void speed_graph_sample() {
  // Only while actually playing: IVEngineClient013 slot 26 IsInGame,
  // slot 84 IsPaused.
  if (g_iface.engine) {
    using BoolFn = bool (*)(void *);
    if (!vfunc<BoolFn>(g_iface.engine, 26)(g_iface.engine))
      return;
    if (vfunc<BoolFn>(g_iface.engine, 84)(g_iface.engine))
      return;
  }
  double now = esp_now();
  if (now - g_speed_last_sample < 0.1)
    return;
  g_speed_last_sample = now;
  float speed = 0.0f;
  int local = engine_get_local_player();
  if (local > 0 && g_net.velocity >= 0) {
    void *ent = entitylist_get(local);
    if (ent) {
      const float *v = (const float *)((uintptr_t)ent + g_net.velocity);
      speed = sqrtf(v[0] * v[0] + v[1] * v[1]);
    }
  }
  g_speed_samples[g_speed_head] = speed;
  g_speed_head = (g_speed_head + 1) % SPEED_SAMPLES;
}

static void draw_speed_graph() {
  if (!esp_option(ESP_OPT_SHOW_SPEEDGRAPH))
    return;
  speed_graph_sample();

  float maxv = 0.0f;
  for (int i = 0; i < SPEED_SAMPLES; i++)
    if (g_speed_samples[i] > maxv)
      maxv = g_speed_samples[i];
  float scale = maxv > 1.0f ? maxv : 1.0f;

  const int w = 240, h = 64;
  int x = (g_scr_w - w) / 2;
  int y = (g_scr_h * 9) / 10 - h / 2;
  if (x < 0) x = 0;
  if (y < 0) y = 0;

  surf_color(0, 0, 0, 120);
  surf_rect(1, x, y, x + w, y + h);
  surf_color(80, 80, 80, 180);
  surf_rect(0, x, y, x + w, y + h);

  surf_color(0, 255, 200, 220);
  int px = 0, py = 0;
  for (int i = 0; i < SPEED_SAMPLES; i++) {
    int idx = (g_speed_head + i) % SPEED_SAMPLES; // oldest -> newest
    float v = g_speed_samples[idx];
    int sx = x + 1 + (i * (w - 2)) / (SPEED_SAMPLES - 1);
    int sy = y + h - 2 - (int)((v / scale) * (float)(h - 4));
    if (sy < y + 1) sy = y + 1;
    if (i > 0)
      surf_line(px, py, sx, sy);
    px = sx;
    py = sy;
  }

  char label[32];
  snprintf(label, sizeof(label), "max %d", (int)maxv);
  draw_text_col(x + 3, y + 2, label, 200, 200, 200);

  int cur_idx = (g_speed_head + SPEED_SAMPLES - 1) % SPEED_SAMPLES;
  char cur[16];
  snprintf(cur, sizeof(cur), "%d", (int)g_speed_samples[cur_idx]);
  int cur_w = (int)strlen(cur) * 8;
  draw_text_col(x + w - 4 - cur_w, y + 2, cur, 255, 255, 255);
}

// Draw the parent->child bone links. Bone snapshots are world-space matrices
// from SetupBones; project each bone once and reuse for both endpoints.
static void draw_skeleton(const EspTarget &t) {
  int n = bones_count(t.idx);
  if (n <= 0 || n > 256)
    return;
  Vector wp[256];
  float xs[256], ys[256];
  bool ok[256];
  int core_count = 0;
  for (int i = 0; i < n; i++) {
    ok[i] = false;
    if (!bone_is_skeleton_core(t.idx, i))
      continue;
    core_count++;
    ok[i] = bone_pos(t.idx, i, wp[i]) &&
            world_to_screen(wp[i], xs[i], ys[i]) && std::isfinite(xs[i]) &&
            std::isfinite(ys[i]);
  }
  static int logged = 0;
  if (core_count > 0 && logged < 4) {
    logged++;
    logd("skeleton: idx=%d bones=%d core=%d humanoid=%d", t.idx, n, core_count,
         (int)bones_is_humanoid(t.idx));
  }
  int sr, sg, sb;
  relation_rgb(t, sr, sg, sb);
  surf_color(sr, sg, sb, 255);
  for (int i = 0; i < n; i++) {
    if (!ok[i])
      continue;
    int p = bone_nearest_core_parent(t.idx, i);
    if (p >= 0 && p < n && ok[p])
      surf_line((int)xs[p], (int)ys[p], (int)xs[i], (int)ys[i]);
  }
}

// ---------------------------------------------------------------------------
// aimbot v1: nearest hostile NPC head to the crosshair.
// Bounded smoothing: never snap, never overshoot. Each tick moves at most
// MAX_STEP degrees toward the target and stops inside DEADZONE.
// ---------------------------------------------------------------------------

QAngle angle_to(const Vector &from, const Vector &to) {
  float dx = to.x - from.x, dy = to.y - from.y, dz = to.z - from.z;
  float horiz = sqrtf(dx * dx + dy * dy);
  if (horiz < 0.001f)
    horiz = 0.001f;
  QAngle a{};
  a.x = -atan2f(dz, horiz) * 180.0f / PI_F; // Source: positive pitch = down
  a.y = atan2f(dy, dx) * 180.0f / PI_F;
  a.z = 0.0f;
  return a;
}

// Server bullet direction adds m_Local.m_vecPunchAngle to the usercmd view
// (GetAutoaimVector), so aim angles have to be pre-subtracted by it.
bool punch_angles(float &px, float &py) {
  px = py = 0.0f;
  if (!aim_punch_enabled() || g_net.punch < 0)
    return false;
  int local = engine_get_local_player();
  if (local <= 0)
    return false;
  void *le = entitylist_get(local);
  if (!le)
    return false;
  const float *p = (const float *)((uintptr_t)le + g_net.punch);
  px = p[0];
  py = p[1];
  return std::isfinite(px) && std::isfinite(py);
}


// Dynamic props are tinted through their client render colour. StudioRender
// feeds m_clrRender into the per-model colour modulation each draw, which is
// why tinting the prop material alone had no effect. (The IStudioRender hook
// experiment corrupted materials and crashed; see studio.cpp.)
void prop_tint_update() {
  static bool applied = false;
  static bool logged_missing = false;
  static bool logged_touched = false;
  bool on = feature_active(FEAT_WORLD_TINT) && g_tint_prop_on;
  if (on)
    studio_props_init();
  if (!on && !applied)
    return;
  if (!g_iface.entitylist || g_net.clr_render < 0) {
    if (on && !logged_missing) {
      logged_missing = true;
      logf("prop tint: m_clrRender unavailable");
    }
    return;
  }
  static double last = 0.0;
  double now = esp_now();
  if (on && now - last < 0.01)
    return;
  last = now;

  using Fn = int (*)(void *);
  int hi = vfunc<Fn>(g_iface.entitylist, 6)(g_iface.entitylist);
  if (hi < 0 || hi > 4096)
    hi = 4096;
  uint32_t col =
      on ? ((uint32_t)g_tint_prop_rgb[0] | ((uint32_t)g_tint_prop_rgb[1] << 8) |
            ((uint32_t)g_tint_prop_rgb[2] << 16) | (255u << 24))
         : 0xFFFFFFFFu;
  int touched = 0;
  for (int idx = 1; idx <= hi; idx++) {
    void *ent = entitylist_get(idx);
    if (!ent)
      continue;
    const char *model = entity_model_name(ent);
    if (!model)
      continue;
    bool prop = strncmp(model, "models/props", 12) == 0 ||
                strncmp(model, "props_", 6) == 0;
    if (!prop)
      continue;
    *(uint32_t *)((uintptr_t)ent + (uintptr_t)g_net.clr_render) = col;
    touched++;
  }
  applied = on;
  if (on && touched > 0 && !logged_touched) {
    logged_touched = true;
    logf("prop tint: %d prop entities", touched);
  }
}

// Small left-edge label, stacked above the box (10 px font + 1 px shadow).
static void draw_left_tag(int left, int y, const char *text, int r, int g,
                          int b) {
  int tw = (int)strlen(text) * 6;
  int tx = left - tw - 3;
  if (tx < 2)
    tx = 2;
  draw_text_small_col(tx + 1, y + 1, text, 0, 0, 0);
  draw_text_small_col(tx, y, text, r, g, b);
}

static const char *alert_tag(int state, int &r, int &g, int &b) {
  switch (state) {
  case 1: r = 170; g = 180; b = 190; return "IDLE";
  case 2: r = 255; g = 220; b = 80; return "ALERT";
  case 3: r = 255; g = 90; b = 70; return "COMBAT";
  case 4: r = 150; g = 200; b = 255; return "SCRIPT";
  default: return nullptr;
  }
}

// Direction markers for hostiles outside the view. Drawn at the screen edge
// using the engine projection when the target is in front, and the view-right
// dot product when it is behind.
static void draw_edge_arrows() {
  if (!g_surface || !g_scr_w || !g_narrows || !esp_option(ESP_OPT_ARROWS))
    return;
  float cx = (float)g_scr_w * 0.5f, cy = (float)g_scr_h * 0.5f;
  const float margin = 26.0f;
  int drawn = 0;
  for (int i = 0; i < g_narrows && drawn < 12; i++) {
    const ArrowTarget &a = g_arrows[i];
    float sx, sy;
    bool proj = world_to_screen(a.head, sx, sy);
    if (proj && sx >= 4.0f && sx <= (float)g_scr_w - 4.0f && sy >= 4.0f &&
        sy <= (float)g_scr_h - 4.0f)
      continue; // already visible as a box
    float dx, dy;
    if (proj) {
      dx = sx - cx;
      dy = sy - cy;
    } else {
      float yaw = g_cam_view.y * PI_F / 180.0f;
      float wx = a.head.x - g_cam_eye.x;
      float wy = a.head.y - g_cam_eye.y;
      float right = wx * sinf(yaw) + wy * (-cosf(yaw));
      dx = right >= 0.0f ? 1.0f : -1.0f;
      dy = 0.0f;
    }
    float len = sqrtf(dx * dx + dy * dy);
    if (len < 1e-3f) {
      dx = 0.0f;
      dy = 1.0f;
      len = 1.0f;
    }
    dx /= len;
    dy /= len;
    float half_w = cx - margin, half_h = cy - margin;
    float tx = fabsf(dx) > 1e-4f ? half_w / fabsf(dx) : 1e9f;
    float ty = fabsf(dy) > 1e-4f ? half_h / fabsf(dy) : 1e9f;
    float d = tx < ty ? tx : ty;
    float ex = cx + dx * d, ey = cy + dy * d;
    float px = -dy, py = dx;
    const int *col = a.neutral ? g_esp_col_neutral : g_esp_col_hostile;
    surf_color(col[0], col[1], col[2], 235);
    surf_line((int)ex, (int)ey, (int)(ex - dx * 13.0f + px * 6.0f),
              (int)(ey - dy * 13.0f + py * 6.0f));
    surf_line((int)ex, (int)ey, (int)(ex - dx * 13.0f - px * 6.0f),
              (int)(ey - dy * 13.0f - py * 6.0f));
    drawn++;
  }
}

// Map transition triggers are server-only brush entities. Draw their world
// bounds and the target map; the previous map is remembered across level
// changes from the worldspawn model name.
struct TransitionBox {
  char next[128];
  Vector mins, maxs;
};
static TransitionBox g_trans[8];
static int g_ntrans = 0;
static char g_map_last[64];
static char g_map_prev[64];

static void map_name_from_world(char *out, size_t outn) {
  out[0] = 0;
  void *w = entitylist_get(0);
  const char *m = w ? entity_model_name(w) : nullptr;
  if (!m)
    return;
  const char *b = strrchr(m, '/');
  b = b ? b + 1 : m;
  size_t n = strcspn(b, ".");
  if (n >= outn)
    n = outn - 1;
  memcpy(out, b, n);
  out[n] = 0;
}

static void transitions_scan() {
  char cur[64];
  map_name_from_world(cur, sizeof(cur));
  if (strcmp(cur, g_map_last) != 0) {
    if (g_map_last[0])
      snprintf(g_map_prev, sizeof(g_map_prev), "%s", g_map_last);
    snprintf(g_map_last, sizeof(g_map_last), "%s", cur);
  }
  int count = server_entity_count();
  int n = 0;
  for (int i = 1; i <= count && n < 8; i++) {
    TransitionBox &b = g_trans[n];
    b.mins = Vector{0, 0, 0};
    b.maxs = Vector{0, 0, 0};
    if (!server_trigger_info(i, b.next, sizeof(b.next), b.mins, b.maxs))
      continue;
    if (b.mins.x == b.maxs.x && b.mins.y == b.maxs.y &&
        b.mins.z == b.maxs.z)
      continue;
    n++;
  }
  g_ntrans = n;
  static int logged = 0;
  if (n > 0 && logged < 4) {
    logged++;
    logf("transitions: %d changelevel trigger(s), next=%s prev=%s", n,
         g_trans[0].next, g_map_prev[0] ? g_map_prev : "?");
  }
}

// Clip a 2D segment to the screen (with a small margin). Liang-Barsky.
static bool clip_line2d(float &x0, float &y0, float &x1, float &y1,
                        float xmin, float ymin, float xmax, float ymax) {
  float dx = x1 - x0, dy = y1 - y0;
  float p[4] = {-dx, dx, -dy, dy};
  float q[4] = {x0 - xmin, xmax - x0, y0 - ymin, ymax - y0};
  float u1 = 0.0f, u2 = 1.0f;
  for (int i = 0; i < 4; i++) {
    if (fabsf(p[i]) < 1e-6f) {
      if (q[i] < 0.0f)
        return false;
      continue;
    }
    float r = q[i] / p[i];
    if (p[i] < 0.0f) {
      if (r > u2) return false;
      if (r > u1) u1 = r;
    } else {
      if (r < u1) return false;
      if (r < u2) u2 = r;
    }
  }
  float nx0 = x0 + u1 * dx, ny0 = y0 + u1 * dy;
  float nx1 = x0 + u2 * dx, ny1 = y0 + u2 * dy;
  x0 = nx0; y0 = ny0; x1 = nx1; y1 = ny1;
  return true;
}

// Project a world-space segment, clipping it at the near plane first. Without
// this an edge with one corner behind the camera was dropped entirely, so a
// partially visible transition box or radius ring disappeared.
bool project_segment(const Vector &a, const Vector &b, int &x0, int &y0,
                     int &x1, int &y1) {
  if (!g_scr_w || !g_scr_h)
    return false;
  float pitch = g_cam_view.x * PI_F / 180.0f;
  float yaw = g_cam_view.y * PI_F / 180.0f;
  float cp = cosf(pitch), sp = sinf(pitch);
  float cy = cosf(yaw), sy = sinf(yaw);
  Vector fwd{cp * cy, cp * sy, -sp};
  Vector da{a.x - g_cam_eye.x, a.y - g_cam_eye.y, a.z - g_cam_eye.z};
  Vector db{b.x - g_cam_eye.x, b.y - g_cam_eye.y, b.z - g_cam_eye.z};
  const float nearz = 5.0f;
  float za = da.x * fwd.x + da.y * fwd.y + da.z * fwd.z;
  float zb = db.x * fwd.x + db.y * fwd.y + db.z * fwd.z;
  if (za <= nearz && zb <= nearz)
    return false;
  Vector ca = a, cb = b;
  if (za <= nearz) {
    float t = (nearz - za) / (zb - za);
    ca = Vector{a.x + (b.x - a.x) * t, a.y + (b.y - a.y) * t,
                a.z + (b.z - a.z) * t};
  } else if (zb <= nearz) {
    float t = (nearz - zb) / (za - zb);
    cb = Vector{b.x + (a.x - b.x) * t, b.y + (a.y - b.y) * t,
                b.z + (a.z - b.z) * t};
  }
  float ax, ay, bx, by;
  if (!world_to_screen(ca, ax, ay) && !project_manual(ca, ax, ay))
    return false;
  if (!world_to_screen(cb, bx, by) && !project_manual(cb, bx, by))
    return false;
  if (!clip_line2d(ax, ay, bx, by, -8.0f, -8.0f, (float)g_scr_w + 8.0f,
                   (float)g_scr_h + 8.0f))
    return false;
  x0 = (int)ax;
  y0 = (int)ay;
  x1 = (int)bx;
  y1 = (int)by;
  return true;
}

static void draw_transitions() {
  if (!g_surface || !g_ntrans)
    return;
  // Corner bits: +x, +y, +z. Twelve edges connect corners differing by one
  // bit; projecting the corners and joining them gives a proper 3D wireframe
  // instead of a screen-space rectangle.
  static const int edges[12][2] = {
      {0, 1}, {2, 3}, {4, 5}, {6, 7}, {0, 2}, {1, 3},
      {4, 6}, {5, 7}, {0, 4}, {1, 5}, {2, 6}, {3, 7}};
  for (int i = 0; i < g_ntrans; i++) {
    const TransitionBox &b = g_trans[i];
    Vector corners[8];
    float xs[8], ys[8];
    bool ok[8];
    int seen = 0;
    for (int c = 0; c < 8; c++) {
      corners[c] = Vector{(c & 1) ? b.maxs.x : b.mins.x,
                          (c & 2) ? b.maxs.y : b.mins.y,
                          (c & 4) ? b.maxs.z : b.mins.z};
      ok[c] = world_to_screen(corners[c], xs[c], ys[c]) &&
              std::isfinite(xs[c]) && std::isfinite(ys[c]);
      if (ok[c])
        seen++;
    }
    if (!seen)
      continue;
    // The trigger whose target is the map we came from is the way back.
    bool back = g_map_prev[0] && strcmp(b.next, g_map_prev) == 0;
    int r = back ? 200 : 255, g = back ? 200 : 170, bl = back ? 200 : 60;
    surf_color(r, g, bl, 210);
    for (int e = 0; e < 12; e++) {
      int a = edges[e][0], c = edges[e][1];
      int lx, ly, hx, hy;
      if (project_segment(corners[a], corners[c], lx, ly, hx, hy))
        surf_line(lx, ly, hx, hy);
    }
    // Tag above the highest projected corner.
    float topx = 0.0f, topy = 1e9f;
    for (int c = 0; c < 8; c++) {
      if (ok[c] && ys[c] < topy) {
        topy = ys[c];
        topx = xs[c];
      }
    }
    char line[128];
    snprintf(line, sizeof(line), "%s %.100s", back ? "<-" : "->", b.next);
    int tx = (int)topx;
    if (tx < 4) tx = 4;
    if (tx > g_scr_w - 120) tx = g_scr_w - 120;
    int ty = (int)topy - 16;
    if (ty < 4) ty = 4;
    draw_text_small_col(tx + 1, ty + 1, line, 0, 0, 0);
    draw_text_small_col(tx, ty, line, r, g, bl);
  }
}

void esp_draw() {
  if (!g_surface || !g_iface.entitylist || !g_net.esp_ok()) return;
  if (!esp_update_screen())
    return;
  esp_collect(engine_get_local_player());
  static double last_trans = 0.0;
  double trans_now = esp_now();
  if (trans_now - last_trans >= 0.25) {
    last_trans = trans_now;
    transitions_scan();
  }
  draw_transitions();
  for (int i = 0; i < g_ntargets; i++) {
    const EspTarget &t = g_targets[i];
    if (t.neutral && !esp_option(ESP_OPT_SHOW_NEUTRAL))
      continue;
    if (esp_option(ESP_OPT_SHOW_SKELETON)) {
      void *ent = entitylist_get(t.idx);
      if (ent && bones_update(t.idx, ent))
        draw_skeleton(t);
    }
    int cr, cg, cb;
    relation_rgb(t, cr, cg, cb);
    surf_color(cr, cg, cb, 255);
    float w = t.h * 0.45f;  // ponytail: constant aspect, no OBB width
    int left = (int)(t.sx - w / 2);
    int right = (int)(t.sx + w / 2);
    int top = (int)(t.sy - t.h);
    int bot = (int)t.sy;
    if (esp_option(ESP_OPT_SHOW_BOX))
      surf_rect(0, left, top, right, bot);
    bool draw_bar = t.show_health && esp_option(ESP_OPT_SHOW_HEALTHBAR);
    bool draw_num = t.show_health && esp_option(ESP_OPT_SHOW_HEALTHNUM);
    int num_x = right + 3;
    if (draw_bar) {
      float frac = t.health / (t.maxhealth > 1.0f ? t.maxhealth : 100.0f);
      if (frac > 1) frac = 1;
      if (frac < 0) frac = 0;
      // vertical bar just right of the box, HP number beside it
      int bx0 = right + 2, bx1 = right + 5;
      surf_color(0, 0, 0, 200);
      surf_rect(1, bx0, top, bx1, bot);
      int fill_top = bot - (int)((float)(bot - top) * frac);
      if (fill_top < top) fill_top = top;
      if (frac > 0.5f) surf_color(40, 255, 40, 255);
      else if (frac > 0.25f) surf_color(255, 255, 0, 255);
      else surf_color(255, 40, 40, 255);
      if (fill_top < bot)
        surf_rect(1, bx0, fill_top, bx1, bot);
      num_x = bx1 + 3;
    }
    if (draw_num) {
      char hptext[16];
      snprintf(hptext, sizeof(hptext), "%d", (int)t.health);
      draw_text_col(num_x, top, hptext, 255, 255, 255);
    }
    if (esp_option(ESP_OPT_SHOW_NAME))
      draw_text_col(left, top - 14, t.name, cr, cg, cb);
    int tag_y = top + 2;
    if (esp_option(ESP_OPT_DAMAGE_TAGS)) {
      const char *tag = nullptr;
      int tr = 255, tg = 255, tb = 255;
      if (t.damage == NPC_DMG_ARMORED) {
        tag = "ARM";
        tr = 255; tg = 170; tb = 60;
      } else if (t.damage == NPC_DMG_VULNERABLE) {
        tag = "VULN";
        tr = 90; tg = 220; tb = 255;
      } else if (t.damage == NPC_DMG_IMMUNE) {
        tag = "IMM";
        tr = 180; tg = 180; tb = 180;
      }
      if (tag) {
        draw_left_tag(left, tag_y, tag, tr, tg, tb);
        tag_y += 12;
      }
    }
    if (esp_option(ESP_OPT_ALERT)) {
      int ar, ag, ab;
      const char *tag = alert_tag(t.state, ar, ag, ab);
      if (tag) {
        draw_left_tag(left, tag_y, tag, ar, ag, ab);
        tag_y += 12;
      }
    }
    if (esp_option(ESP_OPT_WEAPON) && t.weapon[0]) {
      draw_left_tag(left, tag_y, t.weapon, 220, 220, 220);
      tag_y += 12;
    }
  }

  draw_edge_arrows();

  // Groundwork probe: HL2H_BONE_DEBUG=1 draws a white marker at each NPC's
  // "head" hitbox center (from SetupBones + studio hitboxes).
  static bool bone_debug = getenv("HL2H_BONE_DEBUG") != nullptr;
  if (bone_debug) {
    static bool head_logged = false;
    for (int i = 0; i < g_ntargets; i++) {
      const EspTarget &t = g_targets[i];
      void *ent = entitylist_get(t.idx);
      if (!ent || !bones_update(t.idx, ent))
        continue;
      Vector head;
      if (!head_position(t.idx, head)) {
        static int no_head = 0;
        if (no_head < 4) {
          no_head++;
          logd("head: idx=%d no head hitbox/bone", t.idx);
        }
        continue;
      }
      float hx, hy;
      if (!world_to_screen(head, hx, hy))
        continue;
      surf_color(255, 255, 255, 255);
      surf_rect(1, (int)hx - 2, (int)hy - 2, (int)hx + 3, (int)hy + 3);
      if (!head_logged) {
        head_logged = true;
        logd("bone debug: idx=%d bones=%d head=(%.1f %.1f %.1f)", t.idx,
             bones_count(t.idx), head.x, head.y, head.z);
      }
    }
  }

  draw_speed_graph();
}


// ---------------------------------------------------------------------------
// Valuable item tags
// ---------------------------------------------------------------------------