489 lines
14 KiB
C++
489 lines
14 KiB
C++
#include <math.h>
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#include <sys/types.h>
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#include <pthread.h>
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#include "Config.h"
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#include "Gravity.h"
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//#include "powder.h"
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#ifdef GRAVFFT
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#include <fftw3.h>
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#endif
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void Gravity::bilinear_interpolation(float *src, float *dst, int sw, int sh, int rw, int rh)
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{
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int y, x, fxceil, fyceil;
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float fx, fy, fyc, fxc;
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double intp;
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float tr, tl, br, bl;
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//Bilinear interpolation for upscaling
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for (y=0; y<rh; y++)
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for (x=0; x<rw; x++)
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{
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fx = ((float)x)*((float)sw)/((float)rw);
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fy = ((float)y)*((float)sh)/((float)rh);
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fxc = modf(fx, &intp);
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fyc = modf(fy, &intp);
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fxceil = (int)ceil(fx);
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fyceil = (int)ceil(fy);
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if (fxceil>=sw) fxceil = sw-1;
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if (fyceil>=sh) fyceil = sh-1;
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tr = src[sw*(int)floor(fy)+fxceil];
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tl = src[sw*(int)floor(fy)+(int)floor(fx)];
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br = src[sw*fyceil+fxceil];
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bl = src[sw*fyceil+(int)floor(fx)];
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dst[rw*y+x] = ((tl*(1.0f-fxc))+(tr*(fxc)))*(1.0f-fyc) + ((bl*(1.0f-fxc))+(br*(fxc)))*(fyc);
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}
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}
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void Gravity::gravity_init()
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{
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//Allocate full size Gravmaps
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th_ogravmap = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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th_gravmap = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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th_gravy = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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th_gravx = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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th_gravp = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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gravmap = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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gravy = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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gravx = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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gravp = (float *)calloc((XRES/CELL)*(YRES/CELL), sizeof(float));
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gravmask = (unsigned int *)calloc((XRES/CELL)*(YRES/CELL), sizeof(unsigned));
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}
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void Gravity::gravity_cleanup()
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{
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#ifdef GRAVFFT
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grav_fft_cleanup();
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#endif
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}
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void Gravity::gravity_update_async()
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{
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int result;
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if(ngrav_enable)
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{
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pthread_mutex_lock(&gravmutex);
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result = grav_ready;
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if(result) //Did the gravity thread finish?
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{
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//if (!sys_pause||framerender){ //Only update if not paused
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//Switch the full size gravmaps, we don't really need the two above any more
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float *tmpf;
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if(th_gravchanged)
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{
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#if !defined(GRAVFFT) && defined(GRAV_DIFF)
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memcpy(gravy, th_gravy, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memcpy(gravx, th_gravx, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memcpy(gravp, th_gravp, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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#else
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tmpf = gravy;
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gravy = th_gravy;
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th_gravy = tmpf;
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tmpf = gravx;
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gravx = th_gravx;
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th_gravx = tmpf;
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tmpf = gravp;
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gravp = th_gravp;
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th_gravp = tmpf;
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#endif
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}
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tmpf = gravmap;
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gravmap = th_gravmap;
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th_gravmap = tmpf;
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grav_ready = 0; //Tell the other thread that we're ready for it to continue
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pthread_cond_signal(&gravcv);
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//}
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}
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pthread_mutex_unlock(&gravmutex);
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//Apply the gravity mask
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membwand(gravy, gravmask, (XRES/CELL)*(YRES/CELL)*sizeof(float), (XRES/CELL)*(YRES/CELL)*sizeof(unsigned));
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membwand(gravx, gravmask, (XRES/CELL)*(YRES/CELL)*sizeof(float), (XRES/CELL)*(YRES/CELL)*sizeof(unsigned));
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memset(gravmap, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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}
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}
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void *Gravity::update_grav_async_helper(void * context)
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{
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((Gravity *)context)->update_grav_async();
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}
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void Gravity::update_grav_async()
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{
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int done = 0;
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int thread_done = 0;
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memset(th_ogravmap, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(th_gravmap, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(th_gravy, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(th_gravx, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(th_gravp, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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//memset(th_gravy, 0, XRES*YRES*sizeof(float));
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//memset(th_gravx, 0, XRES*YRES*sizeof(float));
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//memset(th_gravp, 0, XRES*YRES*sizeof(float));
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#ifdef GRAVFFT
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grav_fft_init();
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#endif
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while(!thread_done){
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if(!done){
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update_grav();
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done = 1;
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pthread_mutex_lock(&gravmutex);
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grav_ready = done;
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thread_done = gravthread_done;
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pthread_mutex_unlock(&gravmutex);
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} else {
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pthread_mutex_lock(&gravmutex);
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pthread_cond_wait(&gravcv, &gravmutex);
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done = grav_ready;
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thread_done = gravthread_done;
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pthread_mutex_unlock(&gravmutex);
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}
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}
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pthread_exit(NULL);
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}
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void Gravity::start_grav_async()
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{
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if(!ngrav_enable){
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gravthread_done = 0;
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grav_ready = 0;
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pthread_mutex_init (&gravmutex, NULL);
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pthread_cond_init(&gravcv, NULL);
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pthread_create(&gravthread, NULL, &Gravity::update_grav_async_helper, this); //Start asynchronous gravity simulation
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ngrav_enable = 1;
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}
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memset(gravy, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(gravx, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(gravp, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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}
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void Gravity::stop_grav_async()
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{
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if(ngrav_enable){
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pthread_mutex_lock(&gravmutex);
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gravthread_done = 1;
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pthread_cond_signal(&gravcv);
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pthread_mutex_unlock(&gravmutex);
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pthread_join(gravthread, NULL);
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pthread_mutex_destroy(&gravmutex); //Destroy the mutex
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ngrav_enable = 0;
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}
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//Clear the grav velocities
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memset(gravy, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(gravx, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(gravp, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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}
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#ifdef GRAVFFT
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int grav_fft_status = 0;
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float *th_ptgravx, *th_ptgravy, *th_gravmapbig, *th_gravxbig, *th_gravybig;
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fftwf_complex *th_ptgravxt, *th_ptgravyt, *th_gravmapbigt, *th_gravxbigt, *th_gravybigt;
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fftwf_plan plan_gravmap, plan_gravx_inverse, plan_gravy_inverse;
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void Gravity::grav_fft_init()
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{
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int xblock2 = XRES/CELL*2;
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int yblock2 = YRES/CELL*2;
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int x, y, fft_tsize = (xblock2/2+1)*yblock2;
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float distance, scaleFactor;
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fftwf_plan plan_ptgravx, plan_ptgravy;
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if (grav_fft_status) return;
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//use fftw malloc function to ensure arrays are aligned, to get better performance
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th_ptgravx = fftwf_malloc(xblock2*yblock2*sizeof(float));
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th_ptgravy = fftwf_malloc(xblock2*yblock2*sizeof(float));
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th_ptgravxt = fftwf_malloc(fft_tsize*sizeof(fftwf_complex));
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th_ptgravyt = fftwf_malloc(fft_tsize*sizeof(fftwf_complex));
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th_gravmapbig = fftwf_malloc(xblock2*yblock2*sizeof(float));
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th_gravmapbigt = fftwf_malloc(fft_tsize*sizeof(fftwf_complex));
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th_gravxbig = fftwf_malloc(xblock2*yblock2*sizeof(float));
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th_gravybig = fftwf_malloc(xblock2*yblock2*sizeof(float));
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th_gravxbigt = fftwf_malloc(fft_tsize*sizeof(fftwf_complex));
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th_gravybigt = fftwf_malloc(fft_tsize*sizeof(fftwf_complex));
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//select best algorithm, could use FFTW_PATIENT or FFTW_EXHAUSTIVE but that increases the time taken to plan, and I don't see much increase in execution speed
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plan_ptgravx = fftwf_plan_dft_r2c_2d(yblock2, xblock2, th_ptgravx, th_ptgravxt, FFTW_MEASURE);
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plan_ptgravy = fftwf_plan_dft_r2c_2d(yblock2, xblock2, th_ptgravy, th_ptgravyt, FFTW_MEASURE);
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plan_gravmap = fftwf_plan_dft_r2c_2d(yblock2, xblock2, th_gravmapbig, th_gravmapbigt, FFTW_MEASURE);
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plan_gravx_inverse = fftwf_plan_dft_c2r_2d(yblock2, xblock2, th_gravxbigt, th_gravxbig, FFTW_MEASURE);
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plan_gravy_inverse = fftwf_plan_dft_c2r_2d(yblock2, xblock2, th_gravybigt, th_gravybig, FFTW_MEASURE);
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//(XRES/CELL)*(YRES/CELL)*4 is size of data array, scaling needed because FFTW calculates an unnormalized DFT
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scaleFactor = -M_GRAV/((XRES/CELL)*(YRES/CELL)*4);
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//calculate velocity map caused by a point mass
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for (y=0; y<yblock2; y++)
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{
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for (x=0; x<xblock2; x++)
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{
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if (x==XRES/CELL && y==YRES/CELL) continue;
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distance = sqrtf(pow(x-(XRES/CELL), 2) + pow(y-(YRES/CELL), 2));
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th_ptgravx[y*xblock2+x] = scaleFactor*(x-(XRES/CELL)) / pow(distance, 3);
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th_ptgravy[y*xblock2+x] = scaleFactor*(y-(YRES/CELL)) / pow(distance, 3);
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}
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}
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th_ptgravx[yblock2*xblock2/2+xblock2/2] = 0.0f;
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th_ptgravy[yblock2*xblock2/2+xblock2/2] = 0.0f;
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//transform point mass velocity maps
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fftwf_execute(plan_ptgravx);
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fftwf_execute(plan_ptgravy);
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fftwf_destroy_plan(plan_ptgravx);
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fftwf_destroy_plan(plan_ptgravy);
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fftwf_free(th_ptgravx);
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fftwf_free(th_ptgravy);
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//clear padded gravmap
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memset(th_gravmapbig,0,xblock2*yblock2*sizeof(float));
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grav_fft_status = 1;
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}
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void Gravity::grav_fft_cleanup()
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{
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if (!grav_fft_status) return;
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fftwf_free(th_ptgravxt);
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fftwf_free(th_ptgravyt);
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fftwf_free(th_gravmapbig);
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fftwf_free(th_gravmapbigt);
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fftwf_free(th_gravxbig);
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fftwf_free(th_gravybig);
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fftwf_free(th_gravxbigt);
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fftwf_free(th_gravybigt);
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fftwf_destroy_plan(plan_gravmap);
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fftwf_destroy_plan(plan_gravx_inverse);
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fftwf_destroy_plan(plan_gravy_inverse);
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grav_fft_status = 0;
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}
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void Gravity::update_grav()
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{
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int x, y, changed = 0;
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int xblock2 = XRES/CELL*2, yblock2 = YRES/CELL*2;
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int i, fft_tsize = (xblock2/2+1)*yblock2;
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float mr, mc, pr, pc, gr, gc;
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for (y=0; y<YRES/CELL; y++)
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{
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if(changed)
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break;
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for (x=0; x<XRES/CELL; x++)
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{
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if(th_ogravmap[y*(XRES/CELL)+x]!=th_gravmap[y*(XRES/CELL)+x]){
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changed = 1;
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break;
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}
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}
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}
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if(changed)
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{
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th_gravchanged = 1;
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if (!grav_fft_status) grav_fft_init();
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//copy gravmap into padded gravmap array
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for (y=0; y<YRES/CELL; y++)
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{
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for (x=0; x<XRES/CELL; x++)
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{
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th_gravmapbig[(y+YRES/CELL)*xblock2+XRES/CELL+x] = th_gravmap[y*(XRES/CELL)+x];
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}
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}
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//transform gravmap
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fftwf_execute(plan_gravmap);
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//do convolution (multiply the complex numbers)
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for (i=0; i<fft_tsize; i++)
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{
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mr = th_gravmapbigt[i][0];
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mc = th_gravmapbigt[i][1];
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pr = th_ptgravxt[i][0];
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pc = th_ptgravxt[i][1];
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gr = mr*pr-mc*pc;
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gc = mr*pc+mc*pr;
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th_gravxbigt[i][0] = gr;
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th_gravxbigt[i][1] = gc;
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pr = th_ptgravyt[i][0];
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pc = th_ptgravyt[i][1];
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gr = mr*pr-mc*pc;
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gc = mr*pc+mc*pr;
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th_gravybigt[i][0] = gr;
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th_gravybigt[i][1] = gc;
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}
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//inverse transform, and copy from padded arrays into normal velocity maps
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fftwf_execute(plan_gravx_inverse);
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fftwf_execute(plan_gravy_inverse);
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for (y=0; y<YRES/CELL; y++)
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{
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for (x=0; x<XRES/CELL; x++)
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{
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th_gravx[y*(XRES/CELL)+x] = th_gravxbig[y*xblock2+x];
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th_gravy[y*(XRES/CELL)+x] = th_gravybig[y*xblock2+x];
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th_gravp[y*(XRES/CELL)+x] = sqrtf(pow(th_gravxbig[y*xblock2+x],2)+pow(th_gravybig[y*xblock2+x],2));
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}
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}
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}
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else
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{
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th_gravchanged = 0;
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}
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memcpy(th_ogravmap, th_gravmap, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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}
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#else
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// gravity without fast Fourier transforms
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void Gravity::update_grav(void)
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{
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int x, y, i, j, changed = 0;
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float val, distance;
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th_gravchanged = 0;
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#ifndef GRAV_DIFF
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//Find any changed cells
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for (i=0; i<YRES/CELL; i++)
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{
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if(changed)
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break;
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for (j=0; j<XRES/CELL; j++)
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{
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if(th_ogravmap[i*(XRES/CELL)+j]!=th_gravmap[i*(XRES/CELL)+j]){
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changed = 1;
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break;
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}
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}
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}
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if(!changed)
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goto fin;
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memset(th_gravy, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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memset(th_gravx, 0, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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#endif
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th_gravchanged = 1;
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for (i = 0; i < YRES / CELL; i++) {
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for (j = 0; j < XRES / CELL; j++) {
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#ifdef GRAV_DIFF
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if (th_ogravmap[i*(XRES/CELL)+j] != th_gravmap[i*(XRES/CELL)+j])
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{
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#else
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if (th_gravmap[i*(XRES/CELL)+j] > 0.0001f || th_gravmap[i*(XRES/CELL)+j]<-0.0001f) //Only calculate with populated or changed cells.
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{
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#endif
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for (y = 0; y < YRES / CELL; y++) {
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for (x = 0; x < XRES / CELL; x++) {
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if (x == j && y == i)//Ensure it doesn't calculate with itself
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continue;
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distance = sqrt(pow(j - x, 2) + pow(i - y, 2));
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#ifdef GRAV_DIFF
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val = th_gravmap[i*(XRES/CELL)+j] - th_ogravmap[i*(XRES/CELL)+j];
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#else
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val = th_gravmap[i*(XRES/CELL)+j];
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#endif
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th_gravx[y*(XRES/CELL)+x] += M_GRAV * val * (j - x) / pow(distance, 3);
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th_gravy[y*(XRES/CELL)+x] += M_GRAV * val * (i - y) / pow(distance, 3);
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th_gravp[y*(XRES/CELL)+x] += M_GRAV * val / pow(distance, 2);
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}
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}
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}
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}
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}
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fin:
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memcpy(th_ogravmap, th_gravmap, (XRES/CELL)*(YRES/CELL)*sizeof(float));
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}
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#endif
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void Gravity::grav_mask_r(int x, int y, char checkmap[YRES/CELL][XRES/CELL], char shape[YRES/CELL][XRES/CELL], char *shapeout)
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{
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if(x < 0 || x >= XRES/CELL || y < 0 || y >= YRES/CELL)
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return;
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if(x == 0 || y ==0 || y == (YRES/CELL)-1 || x == (XRES/CELL)-1)
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*shapeout = 1;
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checkmap[y][x] = 1;
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shape[y][x] = 1;
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if(x-1 >= 0 && !checkmap[y][x-1] && bmap[y][x-1]!=WL_GRAV)
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grav_mask_r(x-1, y, checkmap, shape, shapeout);
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if(y-1 >= 0 && !checkmap[y-1][x] && bmap[y-1][x]!=WL_GRAV)
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grav_mask_r(x, y-1, checkmap, shape, shapeout);
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if(x+1 < XRES/CELL && !checkmap[y][x+1] && bmap[y][x+1]!=WL_GRAV)
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grav_mask_r(x+1, y, checkmap, shape, shapeout);
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if(y+1 < YRES/CELL && !checkmap[y+1][x] && bmap[y+1][x]!=WL_GRAV)
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|
grav_mask_r(x, y+1, checkmap, shape, shapeout);
|
|
return;
|
|
}
|
|
void Gravity::mask_free(mask_el *c_mask_el){
|
|
if(c_mask_el==NULL)
|
|
return;
|
|
if(c_mask_el->next!=NULL)
|
|
mask_free((mask_el*)c_mask_el->next);
|
|
free(c_mask_el->shape);
|
|
free(c_mask_el);
|
|
}
|
|
void Gravity::gravity_mask()
|
|
{
|
|
char checkmap[YRES/CELL][XRES/CELL];
|
|
int x = 0, y = 0, i, j;
|
|
unsigned maskvalue;
|
|
mask_el *t_mask_el = NULL;
|
|
mask_el *c_mask_el = NULL;
|
|
if(!gravmask)
|
|
return;
|
|
memset(checkmap, 0, sizeof(checkmap));
|
|
for(x = 0; x < XRES/CELL; x++)
|
|
{
|
|
for(y = 0; y < YRES/CELL; y++)
|
|
{
|
|
if(bmap[y][x]!=WL_GRAV && checkmap[y][x] == 0)
|
|
{
|
|
//Create a new shape
|
|
if(t_mask_el==NULL){
|
|
t_mask_el = (mask_el *)malloc(sizeof(mask_el));
|
|
t_mask_el->shape = (char *)malloc((XRES/CELL)*(YRES/CELL));
|
|
memset(t_mask_el->shape, 0, (XRES/CELL)*(YRES/CELL));
|
|
t_mask_el->shapeout = 0;
|
|
t_mask_el->next = NULL;
|
|
c_mask_el = t_mask_el;
|
|
} else {
|
|
c_mask_el->next = (mask_el *)malloc(sizeof(mask_el));
|
|
c_mask_el = (mask_el *)c_mask_el->next;
|
|
c_mask_el->shape = (char *)malloc((XRES/CELL)*(YRES/CELL));
|
|
memset(c_mask_el->shape, 0, (XRES/CELL)*(YRES/CELL));
|
|
c_mask_el->shapeout = 0;
|
|
c_mask_el->next = NULL;
|
|
}
|
|
//Fill the shape
|
|
grav_mask_r(x, y, (char (*)[XRES/CELL])checkmap, (char (*)[XRES/CELL])c_mask_el->shape, (char*)&c_mask_el->shapeout);
|
|
}
|
|
}
|
|
}
|
|
c_mask_el = t_mask_el;
|
|
memset(gravmask, 0, (XRES/CELL)*(YRES/CELL)*sizeof(unsigned));
|
|
while(c_mask_el!=NULL)
|
|
{
|
|
char *cshape = c_mask_el->shape;
|
|
for(x = 0; x < XRES/CELL; x++)
|
|
{
|
|
for(y = 0; y < YRES/CELL; y++)
|
|
{
|
|
if(cshape[y*(XRES/CELL)+x]){
|
|
if(c_mask_el->shapeout)
|
|
maskvalue = 0xFFFFFFFF;
|
|
else
|
|
maskvalue = 0x00000000;
|
|
gravmask[y*(XRES/CELL)+x] = maskvalue;
|
|
}
|
|
}
|
|
}
|
|
c_mask_el = (mask_el*)c_mask_el->next;
|
|
}
|
|
mask_free(t_mask_el);
|
|
}
|
|
|
|
Gravity::Gravity()
|
|
{
|
|
gravity_init();
|
|
}
|