X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?a=blobdiff_plain;f=src%2Fscr%2Fhairball.c;fp=src%2Fscr%2Fhairball.c;h=89c45c348b50f8baec77718316f97aec748f74b8;hb=ba648ddfc62fc6d3f47294aa8bfc10ea6ca3f479;hp=0000000000000000000000000000000000000000;hpb=3398fc6c4188104048f99b650a6cb90beda9b6ed;p=dosdemo

diff --git a/src/scr/hairball.c b/src/scr/hairball.c
new file mode 100644
index 0000000..89c45c3
--- /dev/null
+++ b/src/scr/hairball.c
@@ -0,0 +1,317 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <float.h>
+#include "demo.h"
+#include "3dgfx.h"
+#include "vmath.h"
+#include "screen.h"
+#include "util.h"
+#include "cfgopt.h"
+#include "mesh.h"
+
+
+#ifdef MSDOS
+#include "dos/gfx.h"	/* for wait_vsync assembly macro */
+#else
+void wait_vsync(void);
+#endif
+
+#define NSPAWNPOS	64
+#define SPAWN_RATE	16.0f
+//#define GRAV		(-6.0f)
+#define GRAV		0.0f
+#define HAIR_LENGTH 20
+
+struct particle {
+	vec3_t pos;
+	vec3_t vel;
+	int r, g, b, a;
+	int life;
+
+	struct particle *next;
+};
+
+struct hairball {
+	vec3_t pos;
+	quat_t rot;
+	float xform[16];
+
+	struct particle *plist[NSPAWNPOS];
+};
+
+static int init(void);
+static void destroy(void);
+static void start(long trans_time);
+static void draw(void);
+static void update_hairball(struct hairball *hb, float dt);
+static void draw_hairball(struct hairball *hb);
+
+static struct particle *palloc(void);
+void pfree(struct particle *p);
+
+
+static struct screen scr = {
+	"hairball",
+	init,
+	destroy,
+	start, 0,
+	draw
+};
+
+static long start_time;
+
+static float cam_theta, cam_phi = 15;
+static float cam_dist = 8;
+
+static vec3_t *spawnpos, *spawndir;
+static struct hairball hball;
+static struct g3d_mesh sphmesh;
+
+struct screen *hairball_screen(void)
+{
+	return &scr;
+}
+
+static int init(void)
+{
+	int i, j, numpt = 0;
+
+	gen_sphere_mesh(&sphmesh, 1.0f, 12, 6);
+
+	hball.xform[0] = hball.xform[5] = hball.xform[10] = hball.xform[15] = 1.0f;
+	hball.rot.w = 1.0f;
+
+	if(!(spawnpos = malloc(NSPAWNPOS * sizeof *spawnpos)) ||
+			!(spawndir = malloc(NSPAWNPOS * sizeof *spawndir))) {
+		fprintf(stderr, "failed to allocate spawnpos/dir array\n");
+		return -1;
+	}
+
+	while(numpt < NSPAWNPOS) {
+		float best_dist = -1.0f;
+		for(i=0; i<100; i++) {
+			vec3_t pos = sphrand(1.0f);
+
+			float mindist = FLT_MAX;
+			for(j=0; j<numpt; j++) {
+				float dx = pos.x - spawnpos[i].x;
+				float dy = pos.y - spawnpos[i].y;
+				float dz = pos.z - spawnpos[i].z;
+				float dsq = dx * dx + dy * dy + dz * dz;
+				if(dsq < mindist) {
+					mindist = dsq;
+				}
+			}
+
+			if(mindist > best_dist) {
+				spawnpos[numpt] = pos;
+				best_dist = mindist;
+			}
+		}
+
+		spawndir[numpt] = spawnpos[numpt];
+		++numpt;
+	}
+
+	return 0;
+}
+
+static void destroy(void)
+{
+}
+
+static void start(long trans_time)
+{
+	g3d_matrix_mode(G3D_PROJECTION);
+	g3d_load_identity();
+	g3d_perspective(50.0, 1.33333, 0.5, 100.0);
+
+	start_time = time_msec;
+}
+
+static void update(void)
+{
+	static float prev_mx, prev_my;
+	static long prev_msec;
+	int mouse_dx, mouse_dy;
+	long msec = time_msec - start_time;
+	float dt = (msec - prev_msec) / 1000.0f;
+	prev_msec = msec;
+
+	mouse_dx = mouse_x - prev_mx;
+	mouse_dy = mouse_y - prev_my;
+	prev_mx = mouse_x;
+	prev_my = mouse_y;
+
+
+	if(opt.sball) {
+		memcpy(hball.xform, sball_matrix, 16 * sizeof(float));
+
+		hball.pos.x = hball.xform[12];
+		hball.pos.y = hball.xform[13];
+		hball.pos.z = hball.xform[14];
+	} else {
+		if(mouse_bmask & MOUSE_BN_MIDDLE) {
+			hball.pos.x += mouse_dx * 0.05;
+			hball.pos.y -= mouse_dy * 0.05;
+		}
+
+		quat_to_mat(hball.xform, hball.rot);
+		hball.xform[12] = hball.pos.x;
+		hball.xform[13] = hball.pos.y;
+		hball.xform[14] = hball.pos.z;
+	}
+
+	update_hairball(&hball, dt);
+
+	mouse_orbit_update(&cam_theta, &cam_phi, &cam_dist);
+}
+
+static void draw(void)
+{
+	unsigned long msec;
+	static unsigned long last_swap;
+
+	update();
+
+	memset(fb_pixels, 0, fb_width * fb_height * 2);
+
+	g3d_matrix_mode(G3D_MODELVIEW);
+	g3d_load_identity();
+	g3d_translate(0, 0, -cam_dist);
+	g3d_rotate(cam_phi, 1, 0, 0);
+	g3d_rotate(cam_theta, 0, 1, 0);
+
+	draw_hairball(&hball);
+
+	msec = get_msec();
+	if(msec - last_swap < 16) {
+		wait_vsync();
+	}
+	if(!opt.vsync) {
+		wait_vsync();
+	}
+	swap_buffers(fb_pixels);
+	last_swap = get_msec();
+}
+
+static void update_hairball(struct hairball *hb, float dt)
+{
+	int i, j, spawn_count;
+	struct particle pdummy, *prev, *p;
+	static float spawn_acc;
+
+	/* update particles */
+	for(i=0; i<NSPAWNPOS; i++) {
+		pdummy.next = hb->plist[i];
+		prev = &pdummy;
+		while(prev && prev->next) {
+			p = prev->next;
+			if(--p->life <= 0) {
+				prev->next = p->next;
+				pfree(p);
+				prev = prev->next;
+				continue;
+			}
+
+			p->pos.x += p->vel.x * dt;
+			p->pos.y += p->vel.y * dt;
+			p->pos.z += p->vel.z * dt;
+			p->vel.y += GRAV * dt;
+
+			p->r = p->g = p->b = (p->life << 8) / HAIR_LENGTH - 1;
+
+			prev = p;
+		}
+
+		hb->plist[i] = pdummy.next;
+	}
+
+	/* spawn new particles */
+	spawn_acc += dt;
+	if(spawn_acc >= (1.0f / SPAWN_RATE)) {
+		for(i=0; i<NSPAWNPOS; i++) {
+			struct particle *p = palloc();
+			float *mat = hb->xform;
+			vec3_t pos = spawnpos[i];
+			vec3_t dir = spawndir[i];
+
+			p->pos.x = mat[0] * pos.x + mat[4] * pos.y + mat[8] * pos.z + mat[12];
+			p->pos.y = mat[1] * pos.x + mat[5] * pos.y + mat[9] * pos.z + mat[13];
+			p->pos.z = mat[2] * pos.x + mat[6] * pos.y + mat[10] * pos.z + mat[14];
+
+			p->vel.x = mat[0] * dir.x + mat[4] * dir.y + mat[8] * dir.z;
+			p->vel.y = mat[1] * dir.x + mat[5] * dir.y + mat[9] * dir.z;
+			p->vel.z = mat[2] * dir.x + mat[6] * dir.y + mat[10] * dir.z;
+			p->life = HAIR_LENGTH;
+
+			p->next = hb->plist[i];
+			hb->plist[i] = p;
+		}
+		spawn_acc -= 1.0f / SPAWN_RATE;
+	}
+}
+
+static void draw_hairball(struct hairball *hb)
+{
+	int i, col;
+	struct particle *p;
+	vec3_t prevpos;
+	vec3_t start[NSPAWNPOS];
+
+	for(i=0; i<NSPAWNPOS; i++) {
+		start[i].x = hb->xform[0] * spawnpos[i].x + hb->xform[4] * spawnpos[i].y + hb->xform[8] * spawnpos[i].z + hb->xform[12];
+		start[i].y = hb->xform[1] * spawnpos[i].x + hb->xform[5] * spawnpos[i].y + hb->xform[9] * spawnpos[i].z + hb->xform[13];
+		start[i].z = hb->xform[2] * spawnpos[i].x + hb->xform[6] * spawnpos[i].y + hb->xform[10] * spawnpos[i].z + hb->xform[14];
+	}
+
+	g3d_begin(G3D_LINES);
+	for(i=0; i<NSPAWNPOS; i++) {
+		if(start[i].z >= hb->pos.z) continue;
+		p = hb->plist[i];
+		prevpos = start[i];
+		while(p) {
+			g3d_color3b(p->r, p->g, p->b);
+			g3d_vertex(prevpos.x, prevpos.y, prevpos.z);
+			g3d_vertex(p->pos.x, p->pos.y, p->pos.z);
+			prevpos = p->pos;
+			p = p->next;
+		}
+	}
+	g3d_end();
+
+
+	g3d_push_matrix();
+	g3d_mult_matrix(hb->xform);
+	zsort_mesh(&sphmesh);
+	draw_mesh(&sphmesh);
+	g3d_pop_matrix();
+
+	g3d_begin(G3D_LINES);
+	for(i=0; i<NSPAWNPOS; i++) {
+		if(start[i].z < hb->pos.z) continue;
+		p = hb->plist[i];
+		prevpos = start[i];
+		while(p) {
+			g3d_color3b(p->r, p->g, p->b);
+			g3d_vertex(prevpos.x, prevpos.y, prevpos.z);
+			g3d_vertex(p->pos.x, p->pos.y, p->pos.z);
+			prevpos = p->pos;
+			p = p->next;
+		}
+	}
+	g3d_end();
+
+}
+
+
+static struct particle *palloc(void)
+{
+	return malloc(sizeof(struct particle));
+}
+
+void pfree(struct particle *p)
+{
+	free(p);
+}