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Diffstat (limited to 'src/fov.c')
| -rw-r--r-- | src/fov.c | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/src/fov.c b/src/fov.c new file mode 100644 index 0000000..f60f067 --- /dev/null +++ b/src/fov.c @@ -0,0 +1,136 @@ +/* + * Copyright © 2022 Michael Smith <mikesmiffy128@gmail.com> + * + * Permission to use, copy, modify, and/or distribute this software for any + * purpose with or without fee is hereby granted, provided that the above + * copyright notice and this permission notice appear in all copies. + * + * THE SOFTWARE IS PROVIDED “AS IS” AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH + * REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY + * AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, + * INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM + * LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR + * OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR + * PERFORMANCE OF THIS SOFTWARE. + */ + +// TODO(linux): theoretically, probably ifdef out the cvar-replacement stuff; we +// expect any game that's been ported to linux to already have fov_desired + +#include <stdbool.h> + +#include "con_.h" +#include "engineapi.h" +#include "ent.h" +#include "gametype.h" +#include "hook.h" +#include "intdefs.h" +#include "mem.h" +#include "vcall.h" +#include "x86.h" + +bool changedmax = false; +DEF_CVAR_MINMAX_UNREG(fov_desired, + "Set the base field of view (SST reimplementation)", 75, 75, 120, + CON_HIDDEN | CON_ARCHIVE) +static struct con_var *real_fov_desired; // engine's if it has it, or ours + +typedef void (*VCALLCONV SetDefaultFOV_func)(void *, int); +static SetDefaultFOV_func orig_SetDefaultFOV; +static void VCALLCONV hook_SetDefaultFOV(void *this, int fov) { + // the game normally clamps fov_desired on the server side, disregard + // whatever it tries to set and force our own value instead + orig_SetDefaultFOV(this, con_getvari(real_fov_desired)); +} + +static bool find_SetDefaultFOV(struct con_cmd *fov) { + uchar *fovcb = (uchar *)fov->cb; + int callcnt = 0; + for (uchar *p = fovcb; p - fovcb < 96;) { + // fov command source, and consequent asm, calls 4 functions, one of + // them virtual (i.e. via register). of the 3 direct calls, + // SetDefaultFOV is the third. + if (p[0] == X86_CALL && ++callcnt == 3) { + orig_SetDefaultFOV = (SetDefaultFOV_func)(p + 5 + + mem_loadoffset(p + 1)); + return true; + } + int len = x86_len(p); + if (len == -1) { + con_warn("fov: find_SetDefaultFOV: unknown or invalid instruction\n"); + return false; + } + p += len; + } + return true; +} + +// replacement cvar needs to actively set player fov if in a map +static void fovcb(struct con_var *v) { + void *player = ent_get(1); // NOTE: singleplayer only! + if (player) orig_SetDefaultFOV(player, con_getvari(v)); +} + +// called by sst.c in ClientActive to ensure fov is applied on load +void fov_onload(void) { + if (real_fov_desired == fov_desired) { + void *player = ent_get(1); // " + if (player) orig_SetDefaultFOV(player, con_getvari(fov_desired)); + } +} + +static struct con_cmd *cmd_fov; + +bool fov_init(bool has_ent) { + // could work for other games, but generally only portal 1 people want this + // (the rest of us consider this cheating and a problem for runs...) + if (!GAMETYPE_MATCHES(Portal1)) { return false; } + + cmd_fov = con_findcmd("fov"); + if (!cmd_fov) return false; // shouldn't really happen but just in case! + + if (real_fov_desired = con_findvar("fov_desired")) { + // latest steampipe already goes up to 120 fov + if (real_fov_desired->parent->maxval == 120) return false; + real_fov_desired->parent->maxval = 120; + } + else { + if (!has_ent) return false; + con_reg(fov_desired); + real_fov_desired = fov_desired; + } + if (!find_SetDefaultFOV(cmd_fov)) { + con_warn("fov: couldn't find SetDefaultFOV function\n"); + return false; + } + orig_SetDefaultFOV = (SetDefaultFOV_func)hook_inline( + (void *)orig_SetDefaultFOV, (void *)&hook_SetDefaultFOV); + if (!orig_SetDefaultFOV) { + con_warn("fov: couldn't hook SetDefaultFOV function\n"); + return false; + } + + // we might not be using our cvar but simpler to do this unconditionally + fov_desired->cb = &fovcb; + fov_desired->parent->base.flags &= ~CON_HIDDEN; + // hide the original fov command since we've effectively broken it anyway :) + cmd_fov->base.flags |= CON_DEVONLY; + return true; +} + +void fov_end(void) { + if (real_fov_desired && real_fov_desired != fov_desired) { + real_fov_desired->parent->maxval = 90; + if (con_getvarf(real_fov_desired) > 90) { + con_setvarf(real_fov_desired, 90); // blegh. + } + } + else { + void *player = ent_get(1); // also singleplayer only + if (player) orig_SetDefaultFOV(player, 75); + } + unhook_inline((void *)orig_SetDefaultFOV); + cmd_fov->base.flags &= ~CON_DEVONLY; +} + +// vi: sw=4 ts=4 noet tw=80 cc=80 |