splines.cpp

3D 游戏界的大牛人 John Carmack 终于放出了 Q3 的源代码

/*
===========================================================================
Copyright (C) 1999-2005 Id Software, Inc.

This file is part of Quake III Arena source code.

Quake III Arena source code 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.

Quake III Arena source code 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 Foobar; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
===========================================================================
*/

//#include "stdafx.h"
//#include "qe3.h"

#include "q_shared.hpp"
#include "splines.h"

extern "C" {
int FS_Write( const void *buffer, int len, fileHandle_t h );
int FS_ReadFile( const char *qpath, void **buffer );
void FS_FreeFile( void *buffer );
fileHandle_t FS_FOpenFileWrite( const char *filename );
void FS_FCloseFile( fileHandle_t f );
}

float Q_fabs( float f ) {
	int tmp = * ( int * ) &f;
	tmp &= 0x7FFFFFFF;
	return * ( float * ) &tmp;
}


//#include "../shared/windings.h"
//#include "../qcommon/qcommon.h"
//#include "../sys/sys_public.h"
//#include "../game/game_entity.h"

idCameraDef splineList;
idCameraDef *g_splineList = &splineList;

idVec3_t idSplineList::zero(0,0,0);
/*
void glLabeledPoint(idVec3_t &color, idVec3_t &point, float size, const char *label) {
	qglColor3fv(color);
	qglPointSize(size);
	qglBegin(GL_POINTS);
	qglVertex3fv(point);
	qglEnd();
	idVec3_t v = point;
	v.x += 1;
	v.y += 1;
	v.z += 1;
	qglRasterPos3fv (v);
	qglCallLists (strlen(label), GL_UNSIGNED_BYTE, label);
}


void glBox(idVec3_t &color, idVec3_t &point, float size) {
	idVec3_t mins(point);
	idVec3_t maxs(point);
	mins[0] -= size;
	mins[1] += size;
	mins[2] -= size;
	maxs[0] += size;
	maxs[1] -= size;
	maxs[2] += size;
	qglColor3fv(color);
	qglBegin(GL_LINE_LOOP);
	qglVertex3f(mins[0],mins[1],mins[2]);
	qglVertex3f(maxs[0],mins[1],mins[2]);
	qglVertex3f(maxs[0],maxs[1],mins[2]);
	qglVertex3f(mins[0],maxs[1],mins[2]);
	qglEnd();
	qglBegin(GL_LINE_LOOP);
	qglVertex3f(mins[0],mins[1],maxs[2]);
	qglVertex3f(maxs[0],mins[1],maxs[2]);
	qglVertex3f(maxs[0],maxs[1],maxs[2]);
	qglVertex3f(mins[0],maxs[1],maxs[2]);
	qglEnd();

	qglBegin(GL_LINES);
  	qglVertex3f(mins[0],mins[1],mins[2]);
	qglVertex3f(mins[0],mins[1],maxs[2]);
	qglVertex3f(mins[0],maxs[1],maxs[2]);
	qglVertex3f(mins[0],maxs[1],mins[2]);
	qglVertex3f(maxs[0],mins[1],mins[2]);
	qglVertex3f(maxs[0],mins[1],maxs[2]);
	qglVertex3f(maxs[0],maxs[1],maxs[2]);
	qglVertex3f(maxs[0],maxs[1],mins[2]);
	qglEnd();

}

void splineTest() {
	//g_splineList->load("p:/doom/base/maps/test_base1.camera");
}

void splineDraw() {
	//g_splineList->addToRenderer();
}


//extern void D_DebugLine( const idVec3_t &color, const idVec3_t &start, const idVec3_t &end );

void debugLine(idVec3_t &color, float x, float y, float z, float x2, float y2, float z2) {
	//idVec3_t from(x, y, z);
	//idVec3_t to(x2, y2, z2);
	//D_DebugLine(color, from, to);
}


void idSplineList::addToRenderer() {

	if (controlPoints.Num() == 0) {
		return;
	}

	idVec3_t mins, maxs;
	idVec3_t yellow(1.0, 1.0, 0);
	idVec3_t white(1.0, 1.0, 1.0);
        int i;
        
	for(i = 0; i < controlPoints.Num(); i++) {
		VectorCopy(*controlPoints[i], mins);
		VectorCopy(mins, maxs);
		mins[0] -= 8;
		mins[1] += 8;
		mins[2] -= 8;
		maxs[0] += 8;
		maxs[1] -= 8;
		maxs[2] += 8;
		debugLine( yellow, mins[0], mins[1], mins[2], maxs[0], mins[1], mins[2]);
		debugLine( yellow, maxs[0], mins[1], mins[2], maxs[0], maxs[1], mins[2]);
		debugLine( yellow, maxs[0], maxs[1], mins[2], mins[0], maxs[1], mins[2]);
		debugLine( yellow, mins[0], maxs[1], mins[2], mins[0], mins[1], mins[2]);
		
		debugLine( yellow, mins[0], mins[1], maxs[2], maxs[0], mins[1], maxs[2]);
		debugLine( yellow, maxs[0], mins[1], maxs[2], maxs[0], maxs[1], maxs[2]);
		debugLine( yellow, maxs[0], maxs[1], maxs[2], mins[0], maxs[1], maxs[2]);
		debugLine( yellow, mins[0], maxs[1], maxs[2], mins[0], mins[1], maxs[2]);
	    
	}

	int step = 0;
	idVec3_t step1;
	for(i = 3; i < controlPoints.Num(); i++) {
		for (float tension = 0.0f; tension < 1.001f; tension += 0.1f) {
			float x = 0;
			float y = 0;
			float z = 0;
			for (int j = 0; j < 4; j++) {
				x += controlPoints[i - (3 - j)]->x * calcSpline(j, tension);
				y += controlPoints[i - (3 - j)]->y * calcSpline(j, tension);
				z += controlPoints[i - (3 - j)]->z * calcSpline(j, tension);
			}
			if (step == 0) {
				step1[0] = x;
				step1[1] = y;
				step1[2] = z;
				step = 1;
			} else {
				debugLine( white, step1[0], step1[1], step1[2], x, y, z);
				step = 0;
			}

		}
	}
}
*/

void idSplineList::buildSpline() {
	//int start = Sys_Milliseconds();
	clearSpline();
	for(int i = 3; i < controlPoints.Num(); i++) {
		for (float tension = 0.0f; tension < 1.001f; tension += granularity) {
			float x = 0;
			float y = 0;
			float z = 0;
			for (int j = 0; j < 4; j++) {
				x += controlPoints[i - (3 - j)]->x * calcSpline(j, tension);
				y += controlPoints[i - (3 - j)]->y * calcSpline(j, tension);
				z += controlPoints[i - (3 - j)]->z * calcSpline(j, tension);
			}
			splinePoints.Append(new idVec3_t(x, y, z));
		}
	}
	dirty = false;
	//Com_Printf("Spline build took %f seconds\n", (float)(Sys_Milliseconds() - start) / 1000);
}

/*
void idSplineList::draw(bool editMode) {
	int i;
	vec4_t yellow(1, 1, 0, 1);
        
	if (controlPoints.Num() == 0) {
		return;
	}

	if (dirty) {
		buildSpline();
	}


	qglColor3fv(controlColor);
	qglPointSize(5);
	
	qglBegin(GL_POINTS);
	for (i = 0; i < controlPoints.Num(); i++) {
		qglVertex3fv(*controlPoints[i]);
	}
	qglEnd();
	
	if (editMode) {
		for(i = 0; i < controlPoints.Num(); i++) {
			glBox(activeColor, *controlPoints[i], 4);
		}
	}

	//Draw the curve
	qglColor3fv(pathColor);
	qglBegin(GL_LINE_STRIP);
	int count = splinePoints.Num();
	for (i = 0; i < count; i++) {
		qglVertex3fv(*splinePoints[i]);
	}
	qglEnd();

	if (editMode) {
		qglColor3fv(segmentColor);
		qglPointSize(3);
		qglBegin(GL_POINTS);
		for (i = 0; i < count; i++) {
			qglVertex3fv(*splinePoints[i]);
		}
		qglEnd();
	}
	if (count > 0) {
		//assert(activeSegment >=0 && activeSegment < count);
		if (activeSegment >=0 && activeSegment < count) {
			glBox(activeColor, *splinePoints[activeSegment], 6);
			glBox(yellow, *splinePoints[activeSegment], 8);
		}
	}

}
*/

float idSplineList::totalDistance() {

	if (controlPoints.Num() == 0) {
		return 0.0;
	}

	if (dirty) {
		buildSpline();
	}

	float dist = 0.0;
	idVec3_t temp;
	int count = splinePoints.Num();
	for(int i = 1; i < count; i++) {
		temp = *splinePoints[i-1];
		temp -= *splinePoints[i];
		dist += temp.Length();
	}
	return dist;
}

void idSplineList::initPosition(long bt, long totalTime) {

	if (dirty) {
		buildSpline();
	}

	if (splinePoints.Num() == 0) {
		return;
	}

	baseTime = bt;
	time = totalTime;

	// calc distance to travel ( this will soon be broken into time segments )
	splineTime.Clear();
	splineTime.Append(bt);
	double dist = totalDistance();
	double distSoFar = 0.0;
	idVec3_t temp;
	int count = splinePoints.Num();
	//for(int i = 2; i < count - 1; i++) {
	for(int i = 1; i < count; i++) {
		temp = *splinePoints[i-1];
		temp -= *splinePoints[i];
		distSoFar += temp.Length();
		double percent = distSoFar / dist;
		percent *= totalTime;
		splineTime.Append(percent + bt);
	}
	assert(splineTime.Num() == splinePoints.Num());
	activeSegment = 0;
}



float idSplineList::calcSpline(int step, float tension) {
	switch(step) {
		case 0:	return (pow(1 - tension, 3)) / 6;
		case 1:	return (3 * pow(tension, 3) - 6 * pow(tension, 2) + 4) / 6;
		case 2:	return (-3 * pow(tension, 3) + 3 * pow(tension, 2) + 3 * tension + 1) / 6;
		case 3:	return pow(tension, 3) / 6;
	}
	return 0.0;
}



void idSplineList::updateSelection(const idVec3_t &move) {
	if (selected) {
		dirty = true;
		VectorAdd(*selected, move, *selected);
	}
}


void idSplineList::setSelectedPoint(idVec3_t *p) {
	if (p) {
		p->Snap();
		for(int i = 0; i < controlPoints.Num(); i++) {
			if (*p == *controlPoints[i]) {
				selected = controlPoints[i];
			}
		}
	} else {
		selected = NULL;
	}
}

const idVec3_t *idSplineList::getPosition(long t) {
	static idVec3_t interpolatedPos;
	//static long lastTime = -1;

	int count = splineTime.Num();
	if (count == 0) {
		return &zero;
	}

	Com_Printf("Time: %d\n", t);
	assert(splineTime.Num() == splinePoints.Num());

	while (activeSegment < count) {
		if (splineTime[activeSegment] >= t) {
			if (activeSegment > 0 && activeSegment < count - 1) {
				double timeHi = splineTime[activeSegment + 1];
				double timeLo = splineTime[activeSegment - 1];
				double percent = (timeHi - t) / (timeHi - timeLo); 
				// pick two bounding points
				idVec3_t v1 = *splinePoints[activeSegment-1];
				idVec3_t v2 = *splinePoints[activeSegment+1];
				v2 *= (1.0 - percent);
				v1 *= percent;
				v2 += v1;
				interpolatedPos = v2;
				return &interpolatedPos;
			}
			return splinePoints[activeSegment];
		} else {
			activeSegment++;
		}
	}
	return splinePoints[count-1];
}

void idSplineList::parse(const char *(*text)  ) {
	const char *token;
	//Com_MatchToken( text, "{" );
	do {
		token = Com_Parse( text );
	
		if ( !token[0] ) {
			break;
		}
		if ( !Q_stricmp (token, "}") ) {
			break;
		}

		do {
			// if token is not a brace, it is a key for a key/value pair
			if ( !token[0] || !Q_stricmp (token, "(") || !Q_stricmp(token, "}")) {
				break;
			}

			Com_UngetToken();
			idStr key = Com_ParseOnLine(text);
			const char *token = Com_Parse(text);
			if (Q_stricmp(key.c_str(), "granularity") == 0) {
				granularity = atof(token);
			} else if (Q_stricmp(key.c_str(), "name") == 0) {
				name = token;
			}
			token = Com_Parse(text);

		} while (1);

		if ( !Q_stricmp (token, "}") ) {
			break;
		}