+++ /dev/null
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-#include <math.h>
-#include <errno.h>
-#include "imago2.h"
-#include "3dgfx.h"
-#include "smoketxt.h"
-#include "util.h"
-#include "noise.h"
-
-/* if defined, use bilinear interpolation for dispersion field vectors */
-#define BILERP_FIELD
-/* if defined randomize field vectors by RAND_FIELD_MAX */
-#define RANDOMIZE_FIELD
-
-#define RAND_FIELD_MAX 0.7
-
-#define DFL_PCOUNT 4000
-#define DFL_MAX_LIFE 7.0f
-#define DFL_PALPHA 1.0f
-#define DFL_ZBIAS 0.25
-#define DFL_DRAG 0.95
-#define DFL_FORCE 0.07
-#define DFL_FREQ 0.085
-
-struct vec2 {
- float x, y;
-};
-
-struct vec3 {
- float x, y, z;
-};
-
-struct particle {
- float x, y, z;
- float vx, vy, vz; /* velocity */
- int r, g, b;
- float life;
-};
-
-struct emitter {
- struct particle *plist;
- int pcount;
-
- struct vec3 wind;
- float drag;
- float max_life;
-
- struct g3d_vertex *varr;
-};
-
-struct vfield {
- struct vec2 pos, size;
-
- int width, height;
- int xshift;
- struct vec2 *v;
-};
-
-
-struct smktxt {
- struct emitter em;
- struct vfield vfield;
-
- unsigned char *img_pixels;
- int img_xsz, img_ysz;
-};
-
-static int init_emitter(struct emitter *em, int num, unsigned char *map, int xsz, int ysz);
-static int load_vfield(struct vfield *vf, const char *fname);
-static void vfield_eval(struct vfield *vf, float x, float y, struct vec2 *dir);
-
-struct smktxt *create_smktxt(const char *imgname, const char *vfieldname)
-{
- struct smktxt *stx;
-
- if(!imgname) return 0;
-
- if(!(stx = calloc(sizeof *stx, 1))) {
- return 0;
- }
- if(!(stx->img_pixels = img_load_pixels(imgname, &stx->img_xsz, &stx->img_ysz, IMG_FMT_GREY8))) {
- fprintf(stderr, "create_smktxt: failed to load particle spawnmap: %s\n", imgname);
- free(stx);
- return 0;
- }
-
- stx->em.pcount = DFL_PCOUNT;
- stx->em.wind.z = 0.01;
- stx->em.drag = DFL_DRAG;
- stx->em.max_life = DFL_MAX_LIFE;
-
- if(vfieldname) {
- if(load_vfield(&stx->vfield, vfieldname) == -1) {
- img_free_pixels(stx->img_pixels);
- free(stx);
- return 0;
- }
- }
-
- return stx;
-}
-
-void destroy_smktxt(struct smktxt *stx)
-{
- if(!stx) return;
-
- img_free_pixels(stx->img_pixels);
- free(stx);
-}
-
-int gen_smktxt_vfield(struct smktxt *stx, int xres, int yres, float xfreq, float yfreq)
-{
- int i, j;
- unsigned int tmp;
- struct vec2 *vptr;
- struct vfield *vf = &stx->vfield;
-
- if(!(vf->v = malloc(xres * yres * sizeof *vf->v))) {
- fprintf(stderr, "failed to allocate %dx%d vector field\n", xres, yres);
- return -1;
- }
-
- vf->width = xres;
- vf->height = yres;
- vf->pos.x = vf->pos.y = 0.0f;
- vf->size.x = vf->size.y = 1.0f;
-
- /* assume xres is pow2 otherwise fuck you */
- tmp = xres - 1;
- vf->xshift = 0;
- while(tmp) {
- ++vf->xshift;
- tmp >>= 1;
- }
-
- vptr = vf->v;
- for(i=0; i<yres; i++) {
- for(j=0; j<xres; j++) {
- float x = noise3(j * xfreq, i * yfreq, 0.5);
- float y = noise3(j * xfreq, i * yfreq, 10.5);
- float len = sqrt(x * x + y * y);
- if(len == 0.0f) len = 1.0f;
-
- vptr->x = x / len;
- vptr->y = y / len;
-
- ++vptr;
- }
- }
- return 0;
-}
-
-int dump_smktxt_vfield(struct smktxt *stx, const char *fname)
-{
- FILE *fp;
- int xsz, ysz;
-
- if(!(fp = fopen(fname, "wb"))) {
- fprintf(stderr, "failed to open %s for writing: %s\n", fname, strerror(errno));
- return -1;
- }
-
- xsz = stx->vfield.width;
- ysz = stx->vfield.height;
-
- fwrite(&xsz, sizeof xsz, 1, fp);
- fwrite(&ysz, sizeof ysz, 1, fp);
- fwrite(stx->vfield.v, sizeof *stx->vfield.v, xsz * ysz, fp);
- fclose(fp);
- return 0;
-}
-
-void set_smktxt_wind(struct smktxt *stx, float x, float y, float z)
-{
- stx->em.wind.x = x;
- stx->em.wind.y = y;
- stx->em.wind.z = z;
-}
-
-void set_smktxt_plife(struct smktxt *stx, float life)
-{
- stx->em.max_life = life;
-}
-
-void set_smktxt_pcount(struct smktxt *stx, int count)
-{
- free(stx->em.plist);
- stx->em.plist = 0;
- stx->em.pcount = count;
-}
-
-void set_smktxt_drag(struct smktxt *stx, float drag)
-{
- stx->em.drag = drag;
-}
-
-void update_smktxt(struct smktxt *stx, float dt)
-{
- int i;
- struct vec2 accel;
- struct particle *p;
- struct g3d_vertex *v;
-
- if(!stx->em.plist) {
- if(init_emitter(&stx->em, stx->em.pcount, stx->img_pixels, stx->img_xsz, stx->img_ysz) == -1) {
- fprintf(stderr, "failed to initialize emitter with %d particles\n", stx->em.pcount);
- return;
- }
- }
-
- p = stx->em.plist;
- v = stx->em.varr;
-
- for(i=0; i<stx->em.pcount; i++) {
- vfield_eval(&stx->vfield, p->x, p->y, &accel);
- p->x += p->vx * stx->em.drag * dt;
- p->y += p->vy * stx->em.drag * dt;
- p->z += p->vz * stx->em.drag * dt;
- p->vx += (stx->em.wind.x + accel.x * DFL_FORCE) * dt;
- p->vy += (stx->em.wind.y + accel.y * DFL_FORCE) * dt;
- p->vz += (stx->em.wind.z + p->z * DFL_ZBIAS) * dt;
- p->life -= dt;
- if(p->life < 0.0f) p->life = 0.0f;
-
- v->x = p->x;
- v->y = p->y;
- v->z = p->z;
- v->w = 1.0f;
- v->a = cround64(p->life * 255.0f / stx->em.max_life);
- v->r = 0;
- v->g = (v->a & 0xe0) >> 3;
- v->b = (v->a & 0x1f) << 3;
- ++v;
-
- ++p;
- }
-}
-
-void draw_smktxt(struct smktxt *stx)
-{
- g3d_draw(G3D_POINTS, stx->em.varr, stx->em.pcount);
-}
-
-
-static int init_emitter(struct emitter *em, int num, unsigned char *map, int xsz, int ysz)
-{
- int i, x, y;
- float aspect = (float)xsz / (float)ysz;
- struct particle *p;
-
- free(em->varr);
- if(!(em->varr = malloc(num * sizeof *em->varr))) {
- fprintf(stderr, "failed to allocate particle vertex array (%d verts)\n", num);
- return -1;
- }
-
- free(em->plist);
- if(!(em->plist = malloc(num * sizeof *em->plist))) {
- free(em->varr);
- return -1;
- }
- em->pcount = num;
-
- p = em->plist;
- for(i=0; i<num; i++) {
- do {
- x = rand() % xsz;
- y = rand() % ysz;
- } while(map[y * xsz + x] < 128);
-
- p->x = (float)x / (float)xsz - 0.5;
- p->y = -(float)y / (float)xsz + 0.5 / aspect;
- p->z = ((float)i / (float)num * 2.0 - 1.0) * 0.005;
- p->r = p->g = p->b = 255;
- p->vx = p->vy = p->vz = 0.0f;
- p->life = em->max_life;
- ++p;
- }
- return 0;
-}
-
-static int load_vfield(struct vfield *vf, const char *fname)
-{
- FILE *fp;
- int tmp;
-
- if(!(fp = fopen(fname, "rb"))) {
- fprintf(stderr, "failed to open vector field: %s\n", fname);
- return -1;
- }
- if(fread(&vf->width, sizeof vf->width, 1, fp) < 1 ||
- fread(&vf->height, sizeof vf->height, 1, fp) < 1) {
- fprintf(stderr, "load_vfield: unexpected end of file while reading header\n");
- fclose(fp);
- return -1;
- }
-
- /* assume xsz is pow2 otherwise fuck you */
- tmp = vf->width - 1;
- vf->xshift = 0;
- while(tmp) {
- ++vf->xshift;
- tmp >>= 1;
- }
-
- if(!(vf->v = malloc(vf->width * vf->height * sizeof *vf->v))) {
- fprintf(stderr, "failed to allocate %dx%d vector field\n", vf->width, vf->height);
- fclose(fp);
- return -1;
- }
- if(fread(vf->v, sizeof *vf->v, vf->width * vf->height, fp) < vf->width * vf->height) {
- fprintf(stderr, "load_vfield: unexpected end of file while reading %dx%d vector field\n",
- vf->width, vf->height);
- fclose(fp);
- return -1;
- }
- fclose(fp);
-
- vf->pos.x = vf->pos.y = 0;
- vf->size.x = vf->size.y = 1;
- return 0;
-}
-
-static void vfield_eval(struct vfield *vf, float x, float y, struct vec2 *dir)
-{
- int px, py;
- float tx, ty;
- struct vec2 *p1, *p2;
- struct vec2 left, right;
-
- x = ((x - vf->pos.x) / vf->size.x + 0.5f) * vf->width;
- y = ((y - vf->pos.y) / vf->size.y + 0.5f) * vf->height;
- x = floor(x);
- y = floor(y);
-
- if(x < 0) x = 0;
- if(y < 0) y = 0;
- if(x > vf->width - 2) x = vf->width - 2;
- if(y > vf->height - 2) y = vf->height - 2;
-
- px = (int)x;
- py = (int)y;
-
- p1 = vf->v + (py << vf->xshift) + px;
-#ifdef BILERP_FIELD
- p2 = p1 + vf->width;
-
- tx = fmod(x, 1.0f);
- ty = fmod(y, 1.0f);
-
- left.x = p1->x + (p2->x - p1->x) * ty;
- left.y = p1->y + (p2->y - p1->y) * ty;
- ++p1;
- ++p2;
- right.x = p1->x + (p2->x - p1->x) * ty;
- right.y = p1->y + (p2->y - p1->y) * ty;
-
- dir->x = left.x + (right.x - left.x) * tx;
- dir->y = left.y + (right.y - left.y) * ty;
-#else
- dir->x = p1->x;
- dir->y = p1->y;
-#endif
-
-#ifdef RANDOMIZE_FIELD
- dir->x += ((float)rand() / RAND_MAX - 0.5) * RAND_FIELD_MAX;
- dir->y += ((float)rand() / RAND_MAX - 0.5) * RAND_FIELD_MAX;
-#endif
-}
projects / dosdemo / blobdiff