Xash3DArchive/engine/client/cl_view.c

/*
Copyright (C) 1997-2001 Id Software, Inc.

This program is free software; you can redistribute it and/or
modify it under the terms of the GNU General Public License
as published by the Free Software Foundation; either version 2
of the License, or (at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  

See the GNU General Public License for more details.

You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// cl_view.c -- player rendering positioning

#include "common.h"
#include "client.h"
#include "const.h"

/*
====================
V_ClearScene

Specifies the model that will be used as the world
====================
*/
void V_ClearScene( void )
{
	re->ClearScene();
}

/*
====================
V_CalcFov
====================
*/
float V_CalcFov( float fov_x, float width, float height )
{
	float	fov_y, x, rad = 360.0f * M_PI;

	// check to avoid division by zero
	if( fov_x == 0 ) Host_Error( "V_CalcFov: null fov!\n" );

	// make sure that fov in-range
	fov_x = bound( 1, fov_x, 179 );
	x = width / tan( fov_x / rad );
	fov_y = atan2( height, x );
	fov_y = (fov_y * rad);

	return fov_y;
}

/*
===============
V_SetupRefDef

update refdef values each frame
===============
*/
void V_SetupRefDef( void )
{
	int		i;
	float		lerp, backlerp;
	frame_t		*oldframe;
	entity_state_t	*ps, *ops;

	// find the previous frame to interpolate from
	ps = &cl.frame.ps;
	i = (cl.frame.serverframe - 1) & UPDATE_MASK;
	oldframe = &cl.frames[i];
	if( oldframe->serverframe != cl.frame.serverframe-1 || !oldframe->valid )
		oldframe = &cl.frame; // previous frame was dropped or invalid
	ops = &oldframe->ps;

	// see if the player entity was teleported this frame
	if( ps->ed_flags & ESF_NO_PREDICTION )
		ops = ps;	// don't interpolate
	lerp = cl.refdef.lerpfrac;

	if( cl.time > cl.frame.servertime )
	{
		if( cl_showclamp->integer )
			MsgDev( D_NOTE, "cl_highclamp %i\n", cl.time - cl.frame.servertime );
		cl.time = cl.frame.servertime;
		cl.refdef.lerpfrac = 1.0f;
	}
	else if( cl.time < cl.frame.servertime - Host_FrameTime())
	{
		if( cl_showclamp->integer )
			MsgDev( D_NOTE, "cl_lowclamp %i\n", cl.frame.servertime - Host_FrameTime() - cl.time );
		cl.time = cl.frame.servertime - Host_FrameTime();
		cl.refdef.lerpfrac = 0.0f;
	}
	else cl.refdef.lerpfrac = 1.0 - (cl.frame.servertime - cl.time) * 0.01f;

	// interpolate field of view
	cl.data.fov = ops->fov + cl.refdef.lerpfrac * ( ps->fov - ops->fov );

	VectorCopy( ps->velocity, cl.refdef.velocity );
	VectorCopy( ps->origin, cl.refdef.origin );
	VectorCopy( ops->origin, cl.refdef.prev.origin );
	VectorCopy( ps->angles, cl.refdef.angles );
	VectorCopy( ops->angles, cl.refdef.prev.angles );
	VectorCopy( ps->viewoffset, cl.refdef.viewheight );
	VectorCopy( ops->viewoffset, cl.refdef.prev.viewheight );
	VectorCopy( ps->punch_angles, cl.refdef.punchangle );
	VectorCopy( ops->punch_angles, cl.refdef.prev.punchangle );

	cl.refdef.movevars = &clgame.movevars;

	if( ps->flags & FL_ONGROUND )
		cl.refdef.onground = EDICT_NUM( ps->groundent );
	else cl.refdef.onground = NULL;
	cl.refdef.clientnum = cl.playernum; // not a entity num
	cl.refdef.viewmodel = ps->viewmodel;
	cl.refdef.health = ps->health;
	cl.refdef.num_entities = clgame.numEntities;
	cl.refdef.max_entities = clgame.maxEntities;
	cl.refdef.max_clients = clgame.maxClients;
	cl.refdef.oldtime = (cl.oldtime * 0.001f);
	cl.refdef.time = (cl.time * 0.001f); // cl.time for right lerping
	cl.refdef.frametime = cls.frametime;
	cl.refdef.demoplayback = cls.demoplayback;
	cl.refdef.demorecord = cls.demorecording;
	cl.refdef.paused = cl_paused->integer;
	cl.refdef.predicting = cl_predict->integer;

	// invalid values
	cl.refdef.waterlevel = 0;	// FIXME: calc it again
	cl.refdef.smoothing = 0;	// FIXME: detect right settings
	cl.refdef.viewentity = NULL; // remove ???
	VectorClear( cl.refdef.crosshairangle );

	// calculate the origin
	if( cl.refdef.predicting && !cl.refdef.demoplayback )
	{	
		// use predicted values
		int delta;

		backlerp = 1.0 - lerp;
		for( i = 0; i < 3; i++ )
		{
			cl.refdef.vieworg[i] = cl.predicted_origin[i] + ops->viewoffset[i] 
				+ cl.refdef.lerpfrac * (ps->viewoffset[i] - ops->viewoffset[i]) - backlerp * cl.prediction_error[i];
		}

		// smooth out stair climbing
		delta = cls.realtime - cl.predicted_step_time;
		if( delta < Host_FrameTime()) cl.refdef.vieworg[2] -= cl.predicted_step * (Host_FrameTime() - delta) * 0.01f;

		// in-game use predicted values
		for( i = 0; i < 3; i++ ) cl.refdef.viewangles[i] = cl.predicted_angles[i];
	}
}

/*
===============
V_ApplyRefDef

apply pre-calculated values
===============
*/
void V_ApplyRefDef( void )
{
	cl.refdef.areabits = cl.frame.areabits;
	cl.refdef.fov_y = V_CalcFov( cl.refdef.fov_x, cl.refdef.viewport[2], cl.refdef.viewport[3] );

	if( cl.frame.ps.renderfx == kRenderFxUnderwater )
	{
		float f = com.sin( cl.time * 0.001 * 0.4 * (M_PI * 2.7));
		cl.refdef.fov_x += f;
		cl.refdef.fov_y -= f;
	}
	if( cl.viewent.v.modelindex )
	{
		re->AddRefEntity( &cl.viewent, ED_VIEWMODEL, cl.refdef.lerpfrac );
	}
}

/*
===============
V_CalcRefDef

sets cl.refdef view values
===============
*/
void V_CalcRefDef( void )
{
	cls.dllFuncs.pfnCalcRefdef( &cl.refdef );
}

//============================================================================

/*
==================
V_RenderView

==================
*/
void V_RenderView( void )
{
	if( !cl.video_prepped ) return; // still loading

	// an invalid frame will just use the exact previous refdef
	// we can't use the old frame if the video mode has changed, though...
	if( cl.frame.valid && (cl.force_refdef || !cl_paused->value ))
	{
		cl.force_refdef = false;
		V_ClearScene();

		// build a refresh entity list and calc cl.sim*
		// this also calls CL_CalcViewValues which loads
		// refdef.forward, etc.
		CL_AddEntities ();

		V_SetupRefDef ();
		V_CalcRefDef ();
		V_ApplyRefDef ();
	}
	re->RenderFrame( &cl.refdef );
}

/*
==================
V_PreRender

==================
*/
bool V_PreRender( void )
{
	// too early
	if( !re ) return false;
		
	re->BeginFrame();
	SCR_FillRect( 0, 0, SCREEN_WIDTH, SCREEN_HEIGHT, g_color_table[0] );
	return true;
}

/*
==================
V_PostRender

==================
*/
void V_PostRender( void )
{
	SCR_DrawNet();
	SCR_DrawFPS();
	UI_Draw();
	Con_DrawConsole();
	re->EndFrame();
}