X-Git-Url: http://git.mutantstargoat.com/user/nuclear/?p=dosdemo;a=blobdiff_plain;f=tools%2Fropesim%2Fsrc%2Fcmesh.c;fp=tools%2Fropesim%2Fsrc%2Fcmesh.c;h=64ed2d0c04ed864e55b3ebfa15f788595beb3a6c;hp=0000000000000000000000000000000000000000;hb=be72aee3c4a0a5516bdccf06c5419efe3e026ee4;hpb=e8b26db00c934d141f16652cb8dcbeae23b17e48

diff --git a/tools/ropesim/src/cmesh.c b/tools/ropesim/src/cmesh.c
new file mode 100644
index 0000000..64ed2d0
--- /dev/null
+++ b/tools/ropesim/src/cmesh.c
@@ -0,0 +1,1619 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <limits.h>
+#include <float.h>
+#include <assert.h>
+#include "opengl.h"
+#include "cmesh.h"
+
+
+struct cmesh_vattrib {
+	int nelem;	/* num elements per attribute [1, 4] */
+	float *data;
+	unsigned int count;
+	unsigned int vbo;
+	int vbo_valid, data_valid;
+};
+
+/* istart,icount are valid only when the mesh is indexed, otherwise icount is 0.
+ * vstart,vcount are define the submesh for non-indexed meshes.
+ * For indexed meshes, vstart,vcount denote the range of vertices used by each
+ * submesh.
+ */
+struct submesh {
+	char *name;
+	int nfaces;	/* derived from either icount or vcount */
+	int istart, icount;
+	int vstart, vcount;
+	struct submesh *next;
+};
+
+struct cmesh {
+	char *name;
+	unsigned int nverts, nfaces;
+
+	struct submesh *sublist;
+	int subcount;
+
+	/* current value for each attribute for the immediate mode interface */
+	cgm_vec4 cur_val[CMESH_NUM_ATTR];
+
+	unsigned int buffer_objects[CMESH_NUM_ATTR + 1];
+	struct cmesh_vattrib vattr[CMESH_NUM_ATTR];
+
+	unsigned int *idata;
+	unsigned int icount;
+	unsigned int ibo;
+	int ibo_valid, idata_valid;
+
+	/* index buffer for wireframe rendering (constructed on demand) */
+	unsigned int wire_ibo;
+	int wire_ibo_valid;
+
+	/* axis-aligned bounding box */
+	cgm_vec3 aabb_min, aabb_max;
+	int aabb_valid;
+	/* bounding sphere */
+	cgm_vec3 bsph_center;
+	float bsph_radius;
+	int bsph_valid;
+};
+
+
+static int clone(struct cmesh *cmdest, struct cmesh *cmsrc, struct submesh *sub);
+static int pre_draw(struct cmesh *cm);
+static void post_draw(struct cmesh *cm, int cur_sdr);
+static void update_buffers(struct cmesh *cm);
+static void update_wire_ibo(struct cmesh *cm);
+static void calc_aabb(struct cmesh *cm);
+static void calc_bsph(struct cmesh *cm);
+
+static int def_nelem[CMESH_NUM_ATTR] = {3, 3, 3, 2, 4, 4, 4, 2};
+
+static int sdr_loc[CMESH_NUM_ATTR] = {0, 1, 2, 3, 4, 5, 6, 7};
+static int use_custom_sdr_attr;
+
+
+/* global state */
+void cmesh_set_attrib_sdrloc(int attr, int loc)
+{
+	sdr_loc[attr] = loc;
+}
+
+int cmesh_get_attrib_sdrloc(int attr)
+{
+	return sdr_loc[attr];
+}
+
+void cmesh_clear_attrib_sdrloc(void)
+{
+	int i;
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		sdr_loc[i] = -1;
+	}
+}
+
+/* mesh functions */
+struct cmesh *cmesh_alloc(void)
+{
+	struct cmesh *cm;
+
+	if(!(cm = malloc(sizeof *cm))) {
+		return 0;
+	}
+	if(cmesh_init(cm) == -1) {
+		free(cm);
+		return 0;
+	}
+	return cm;
+}
+
+void cmesh_free(struct cmesh *cm)
+{
+	cmesh_destroy(cm);
+	free(cm);
+}
+
+int cmesh_init(struct cmesh *cm)
+{
+	int i;
+
+	memset(cm, 0, sizeof *cm);
+	cgm_wcons(cm->cur_val + CMESH_ATTR_COLOR, 1, 1, 1, 1);
+
+	glGenBuffers(CMESH_NUM_ATTR + 1, cm->buffer_objects);
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		cm->vattr[i].vbo = cm->buffer_objects[i];
+	}
+
+	cm->ibo = cm->buffer_objects[CMESH_NUM_ATTR];
+	return 0;
+}
+
+void cmesh_destroy(struct cmesh *cm)
+{
+	int i;
+
+	free(cm->name);
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		free(cm->vattr[i].data);
+	}
+	free(cm->idata);
+
+	cmesh_clear_submeshes(cm);
+
+	glDeleteBuffers(CMESH_NUM_ATTR + 1, cm->buffer_objects);
+	if(cm->wire_ibo) {
+		glDeleteBuffers(1, &cm->wire_ibo);
+	}
+}
+
+void cmesh_clear(struct cmesh *cm)
+{
+	int i;
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		cm->vattr[i].nelem = 0;
+		cm->vattr[i].vbo_valid = 0;
+		cm->vattr[i].data_valid = 0;
+		free(cm->vattr[i].data);
+		cm->vattr[i].data = 0;
+		cm->vattr[i].count = 0;
+	}
+	cm->ibo_valid = cm->idata_valid = 0;
+	free(cm->idata);
+	cm->idata = 0;
+	cm->icount = 0;
+
+	cm->wire_ibo_valid = 0;
+	cm->nverts = cm->nfaces = 0;
+
+	cm->bsph_valid = cm->aabb_valid = 0;
+
+	cmesh_clear_submeshes(cm);
+}
+
+int cmesh_clone(struct cmesh *cmdest, struct cmesh *cmsrc)
+{
+	return clone(cmdest, cmsrc, 0);
+}
+
+static int clone(struct cmesh *cmdest, struct cmesh *cmsrc, struct submesh *sub)
+{
+	int i, nelem, vstart, vcount, istart, icount;
+	char *srcname, *name = 0;
+	float *varr[CMESH_NUM_ATTR] = {0};
+	float *vptr;
+	unsigned int *iptr, *iarr = 0;
+
+	/* try do anything that can fail first, before making any changes to cmdest
+	 * so we have the option of recovering gracefuly
+	 */
+
+	srcname = sub ? sub->name : cmsrc->name;
+	if(srcname) {
+		if(!(name = malloc(strlen(srcname) + 1))) {
+			return -1;
+		}
+		strcpy(name, srcname);
+	}
+
+	if(sub) {
+		vstart = sub->vstart;
+		vcount = sub->vcount;
+		istart = sub->istart;
+		icount = sub->icount;
+	} else {
+		vstart = istart = 0;
+		vcount = cmsrc->nverts;
+		icount = cmsrc->icount;
+	}
+
+	if(cmesh_indexed(cmsrc)) {
+		if(!(iarr = malloc(icount * sizeof *iarr))) {
+			free(name);
+			return -1;
+		}
+	}
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		if(cmesh_has_attrib(cmsrc, i)) {
+			nelem = cmsrc->vattr[i].nelem;
+			if(!(varr[i] = malloc(vcount * nelem * sizeof(float)))) {
+				while(--i >= 0) {
+					free(varr[i]);
+				}
+				free(iarr);
+				free(name);
+				return -1;
+			}
+		}
+	}
+
+	/* from this point forward nothing can fail */
+	cmesh_clear(cmdest);
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		free(cmdest->vattr[i].data);
+
+		if(cmesh_has_attrib(cmsrc, i)) {
+			cmesh_attrib(cmsrc, i);	/* force validation of the actual data on the source mesh */
+
+			nelem = cmsrc->vattr[i].nelem;
+			cmdest->vattr[i].nelem = nelem;
+			cmdest->vattr[i].data = varr[i];
+			cmdest->vattr[i].count = vcount;
+			vptr = cmsrc->vattr[i].data + vstart * nelem;
+			memcpy(cmdest->vattr[i].data, vptr, vcount * nelem * sizeof(float));
+			cmdest->vattr[i].data_valid = 1;
+			cmdest->vattr[i].vbo_valid = 0;
+		} else {
+			memset(cmdest->vattr + i, 0, sizeof cmdest->vattr[i]);
+		}
+	}
+
+	if(cmesh_indexed(cmsrc)) {
+		cmesh_index(cmsrc);	/* force validation .... */
+
+		cmdest->idata = iarr;
+		cmdest->icount = icount;
+		if(sub) {
+			/* need to offset all vertex indices by -vstart */
+			iptr = cmsrc->idata + istart;
+			for(i=0; i<icount; i++) {
+				cmdest->idata[i] = *iptr++ - vstart;
+			}
+		} else {
+			memcpy(cmdest->idata, cmsrc->idata + istart, icount * sizeof *cmdest->idata);
+		}
+		cmdest->idata_valid = 1;
+	} else {
+		cmdest->idata = 0;
+		cmdest->idata_valid = cmdest->ibo_valid = 0;
+	}
+
+	free(cmdest->name);
+	cmdest->name = name;
+
+	cmdest->nverts = cmsrc->nverts;
+	cmdest->nfaces = sub ? sub->nfaces : cmsrc->nfaces;
+
+	memcpy(cmdest->cur_val, cmsrc->cur_val, sizeof cmdest->cur_val);
+
+	cmdest->aabb_min = cmsrc->aabb_min;
+	cmdest->aabb_max = cmsrc->aabb_max;
+	cmdest->aabb_valid = cmsrc->aabb_valid;
+	cmdest->bsph_center = cmsrc->bsph_center;
+	cmdest->bsph_radius = cmsrc->bsph_radius;
+	cmdest->bsph_valid = cmsrc->bsph_valid;
+
+	/* copy sublist only if we're not cloning a submesh */
+	if(!sub) {
+		struct submesh *sm, *n, *head = 0, *tail = 0;
+
+		sm = cmsrc->sublist;
+		while(sm) {
+			if(!(n = malloc(sizeof *n)) || !(name = malloc(strlen(sm->name) + 1))) {
+				free(n);
+				sm = sm->next;
+				continue;
+			}
+			strcpy(name, sm->name);
+			*n = *sm;
+			n->name = name;
+			n->next = 0;
+
+			if(head) {
+				tail->next = n;
+				tail = n;
+			} else {
+				head = tail = n;
+			}
+
+			sm = sm->next;
+		}
+
+		cmdest->sublist = head;
+		cmdest->subcount = cmsrc->subcount;
+	}
+
+	return 0;
+}
+
+int cmesh_set_name(struct cmesh *cm, const char *name)
+{
+	int len = strlen(name);
+	char *tmp = malloc(len + 1);
+	if(!tmp) return -1;
+	free(cm->name);
+	cm->name = tmp;
+	memcpy(cm->name, name, len + 1);
+	return 0;
+}
+
+const char *cmesh_name(struct cmesh *cm)
+{
+	return cm->name;
+}
+
+int cmesh_has_attrib(struct cmesh *cm, int attr)
+{
+	if(attr < 0 || attr >= CMESH_NUM_ATTR) {
+		return 0;
+	}
+	return cm->vattr[attr].vbo_valid | cm->vattr[attr].data_valid;
+}
+
+int cmesh_indexed(struct cmesh *cm)
+{
+	return cm->ibo_valid | cm->idata_valid;
+}
+
+/* vdata can be 0, in which case only memory is allocated
+ * returns pointer to the attribute array
+ */
+float *cmesh_set_attrib(struct cmesh *cm, int attr, int nelem, unsigned int num,
+		const float *vdata)
+{
+	float *newarr;
+
+	if(attr < 0 || attr >= CMESH_NUM_ATTR) {
+		return 0;
+	}
+	if(cm->nverts && num != cm->nverts) {
+		return 0;
+	}
+
+	if(!(newarr = malloc(num * nelem * sizeof *newarr))) {
+		return 0;
+	}
+	if(vdata) {
+		memcpy(newarr, vdata, num * nelem * sizeof *newarr);
+	}
+
+	cm->nverts = num;
+
+	free(cm->vattr[attr].data);
+	cm->vattr[attr].data = newarr;
+	cm->vattr[attr].count = num * nelem;
+	cm->vattr[attr].nelem = nelem;
+	cm->vattr[attr].data_valid = 1;
+	cm->vattr[attr].vbo_valid = 0;
+	return newarr;
+}
+
+float *cmesh_attrib(struct cmesh *cm, int attr)
+{
+	if(attr < 0 || attr >= CMESH_NUM_ATTR) {
+		return 0;
+	}
+	cm->vattr[attr].vbo_valid = 0;
+	return (float*)cmesh_attrib_ro(cm, attr);
+}
+
+const float *cmesh_attrib_ro(struct cmesh *cm, int attr)
+{
+	void *tmp;
+	int nelem;
+
+	if(attr < 0 || attr >= CMESH_NUM_ATTR) {
+		return 0;
+	}
+
+	if(!cm->vattr[attr].data_valid) {
+#if GL_ES_VERSION_2_0
+		return 0;
+#else
+		if(!cm->vattr[attr].vbo_valid) {
+			return 0;
+		}
+
+		/* local data copy unavailable, grab the data from the vbo */
+		nelem = cm->vattr[attr].nelem;
+		if(!(cm->vattr[attr].data = malloc(cm->nverts * nelem * sizeof(float)))) {
+			return 0;
+		}
+		cm->vattr[attr].count = cm->nverts * nelem;
+
+		glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[attr].vbo);
+		tmp = glMapBuffer(GL_ARRAY_BUFFER, GL_READ_ONLY);
+		memcpy(cm->vattr[attr].data, tmp, cm->nverts * nelem * sizeof(float));
+		glUnmapBuffer(GL_ARRAY_BUFFER);
+
+		cm->vattr[attr].data_valid = 1;
+#endif
+	}
+	return cm->vattr[attr].data;
+}
+
+float *cmesh_attrib_at(struct cmesh *cm, int attr, int idx)
+{
+	float *vptr = cmesh_attrib(cm, attr);
+	return vptr ? vptr + idx * cm->vattr[attr].nelem : 0;
+}
+
+const float *cmesh_attrib_at_ro(struct cmesh *cm, int attr, int idx)
+{
+	const float *vptr = cmesh_attrib_ro(cm, attr);
+	return vptr ? vptr + idx * cm->vattr[attr].nelem : 0;
+}
+
+int cmesh_attrib_count(struct cmesh *cm, int attr)
+{
+	return cmesh_has_attrib(cm, attr) ? cm->nverts : 0;
+}
+
+int cmesh_push_attrib(struct cmesh *cm, int attr, float *v)
+{
+	float *vptr;
+	int i, cursz, newsz;
+
+	if(!cm->vattr[attr].nelem) {
+		cm->vattr[attr].nelem = def_nelem[attr];
+	}
+
+	cursz = cm->vattr[attr].count;
+	newsz = cursz + cm->vattr[attr].nelem;
+	if(!(vptr = realloc(cm->vattr[attr].data, newsz * sizeof(float)))) {
+		return -1;
+	}
+	cm->vattr[attr].data = vptr;
+	cm->vattr[attr].count = newsz;
+	vptr += cursz;
+
+	for(i=0; i<cm->vattr[attr].nelem; i++) {
+		*vptr++ = *v++;
+	}
+	cm->vattr[attr].data_valid = 1;
+	cm->vattr[attr].vbo_valid = 0;
+
+	if(attr == CMESH_ATTR_VERTEX) {
+		cm->nverts = newsz / cm->vattr[attr].nelem;
+	}
+	return 0;
+}
+
+int cmesh_push_attrib1f(struct cmesh *cm, int attr, float x)
+{
+	float v[4];
+	v[0] = x;
+	v[1] = v[2] = 0.0f;
+	v[3] = 1.0f;
+	return cmesh_push_attrib(cm, attr, v);
+}
+
+int cmesh_push_attrib2f(struct cmesh *cm, int attr, float x, float y)
+{
+	float v[4];
+	v[0] = x;
+	v[1] = y;
+	v[2] = 0.0f;
+	v[3] = 1.0f;
+	return cmesh_push_attrib(cm, attr, v);
+}
+
+int cmesh_push_attrib3f(struct cmesh *cm, int attr, float x, float y, float z)
+{
+	float v[4];
+	v[0] = x;
+	v[1] = y;
+	v[2] = z;
+	v[3] = 1.0f;
+	return cmesh_push_attrib(cm, attr, v);
+}
+
+int cmesh_push_attrib4f(struct cmesh *cm, int attr, float x, float y, float z, float w)
+{
+	float v[4];
+	v[0] = x;
+	v[1] = y;
+	v[2] = z;
+	v[3] = w;
+	return cmesh_push_attrib(cm, attr, v);
+}
+
+/* indices can be 0, in which case only memory is allocated
+ * returns pointer to the index array
+ */
+unsigned int *cmesh_set_index(struct cmesh *cm, int num, const unsigned int *indices)
+{
+	unsigned int *tmp;
+	int nidx = cm->nfaces * 3;
+
+	if(nidx && num != nidx) {
+		return 0;
+	}
+
+	if(!(tmp = malloc(num * sizeof *tmp))) {
+		return 0;
+	}
+	if(indices) {
+		memcpy(tmp, indices, num * sizeof *tmp);
+	}
+
+	free(cm->idata);
+	cm->idata = tmp;
+	cm->icount = num;
+	cm->idata_valid = 1;
+	cm->ibo_valid = 0;
+	return tmp;
+}
+
+unsigned int *cmesh_index(struct cmesh *cm)
+{
+	cm->ibo_valid = 0;
+	return (unsigned int*)cmesh_index_ro(cm);
+}
+
+const unsigned int *cmesh_index_ro(struct cmesh *cm)
+{
+	int nidx;
+	unsigned int *tmp;
+
+	if(!cm->idata_valid) {
+#if GL_ES_VERSION_2_0
+		return 0;
+#else
+		if(!cm->ibo_valid) {
+			return 0;
+		}
+
+		/* local copy is unavailable, grab the data from the ibo */
+		nidx = cm->nfaces * 3;
+		if(!(tmp = malloc(nidx * sizeof *cm->idata))) {
+			return 0;
+		}
+		free(cm->idata);
+		cm->idata = tmp;
+		cm->icount = nidx;
+
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cm->ibo);
+		tmp = glMapBuffer(GL_ELEMENT_ARRAY_BUFFER, GL_READ_ONLY);
+		memcpy(cm->idata, tmp, nidx * sizeof *cm->idata);
+		glUnmapBuffer(GL_ELEMENT_ARRAY_BUFFER);
+
+		cm->idata_valid = 1;
+#endif
+	}
+	return cm->idata;
+}
+
+int cmesh_index_count(struct cmesh *cm)
+{
+	return cm->nfaces * 3;
+}
+
+int cmesh_push_index(struct cmesh *cm, unsigned int idx)
+{
+	unsigned int *iptr;
+	unsigned int cur_sz = cm->icount;
+	if(!(iptr = realloc(cm->idata, (cur_sz + 1) * sizeof *iptr))) {
+		return -1;
+	}
+	iptr[cur_sz] = idx;
+	cm->idata = iptr;
+	cm->icount = cur_sz + 1;
+	cm->idata_valid = 1;
+	cm->ibo_valid = 0;
+
+	cm->nfaces = cm->icount / 3;
+	return 0;
+}
+
+int cmesh_poly_count(struct cmesh *cm)
+{
+	if(cm->nfaces) {
+		return cm->nfaces;
+	}
+	if(cm->nverts) {
+		return cm->nverts / 3;
+	}
+	return 0;
+}
+
+/* attr can be -1 to invalidate all attributes */
+void cmesh_invalidate_vbo(struct cmesh *cm, int attr)
+{
+	int i;
+
+	if(attr >= CMESH_NUM_ATTR) {
+		return;
+	}
+
+	if(attr < 0) {
+		for(i=0; i<CMESH_NUM_ATTR; i++) {
+			cm->vattr[i].vbo_valid = 0;
+		}
+	} else {
+		cm->vattr[attr].vbo_valid = 0;
+	}
+}
+
+void cmesh_invalidate_index(struct cmesh *cm)
+{
+	cm->ibo_valid = 0;
+}
+
+int cmesh_append(struct cmesh *cmdest, struct cmesh *cmsrc)
+{
+	int i, nelem, newsz, origsz, srcsz;
+	float *vptr;
+	unsigned int *iptr;
+	unsigned int idxoffs;
+
+	if(!cmdest->nverts) {
+		return cmesh_clone(cmdest, cmsrc);
+	}
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		if(cmesh_has_attrib(cmdest, i) && cmesh_has_attrib(cmsrc, i)) {
+			/* force validation of the data arrays */
+			cmesh_attrib(cmdest, i);
+			cmesh_attrib_ro(cmsrc, i);
+
+			assert(cmdest->vattr[i].nelem == cmsrc->vattr[i].nelem);
+			nelem = cmdest->vattr[i].nelem;
+			origsz = cmdest->nverts * nelem;
+			newsz = cmdest->nverts + cmsrc->nverts * nelem;
+
+			if(!(vptr = realloc(cmdest->vattr[i].data, newsz * sizeof *vptr))) {
+				return -1;
+			}
+			memcpy(vptr + origsz, cmsrc->vattr[i].data, cmsrc->nverts * nelem * sizeof(float));
+			cmdest->vattr[i].data = vptr;
+			cmdest->vattr[i].count = newsz;
+		}
+	}
+
+	if(cmesh_indexed(cmdest)) {
+		assert(cmesh_indexed(cmsrc));
+		/* force validation ... */
+		cmesh_index(cmdest);
+		cmesh_index_ro(cmsrc);
+
+		idxoffs = cmdest->nverts;
+		origsz = cmdest->icount;
+		srcsz = cmsrc->icount;
+		newsz = origsz + srcsz;
+
+		if(!(iptr = realloc(cmdest->idata, newsz * sizeof *iptr))) {
+			return -1;
+		}
+		cmdest->idata = iptr;
+		cmdest->icount = newsz;
+
+		/* copy and fixup all the new indices */
+		iptr += origsz;
+		for(i=0; i<srcsz; i++) {
+			*iptr++ = cmsrc->idata[i] + idxoffs;
+		}
+	}
+
+	cmdest->wire_ibo_valid = 0;
+	cmdest->aabb_valid = 0;
+	cmdest->bsph_valid = 0;
+	return 0;
+}
+
+void cmesh_clear_submeshes(struct cmesh *cm)
+{
+	struct submesh *sm;
+
+	while(cm->sublist) {
+		sm = cm->sublist;
+		cm->sublist = cm->sublist->next;
+		free(sm->name);
+		free(sm);
+	}
+	cm->subcount = 0;
+}
+
+int cmesh_submesh(struct cmesh *cm, const char *name, int fstart, int fcount)
+{
+	int i;
+	unsigned int minv = UINT_MAX, maxv = 0;
+	unsigned int *iptr;
+	struct submesh *sm;
+
+	if(fstart < 0 || fcount < 1 || fstart + fcount > cm->nfaces) {
+		return -1;
+	}
+
+	if(!(sm = malloc(sizeof *sm)) || !(sm->name = malloc(strlen(name) + 1))) {
+		free(sm);
+		return -1;
+	}
+	strcpy(sm->name, name);
+	sm->nfaces = fcount;
+
+	if(cmesh_indexed(cm)) {
+		sm->istart = fstart * 3;
+		sm->icount = fcount * 3;
+
+		/* find out which vertices are used by this submesh */
+		iptr = cm->idata + sm->istart;
+		for(i=0; i<sm->icount; i++) {
+			unsigned int vidx = *iptr++;
+			if(vidx < minv) minv = vidx;
+			if(vidx > maxv) maxv = vidx;
+		}
+		sm->vstart = minv;
+		sm->vcount = maxv - minv + 1;
+	} else {
+		sm->istart = sm->icount = 0;
+		sm->vstart = fstart * 3;
+		sm->vcount = fcount * 3;
+	}
+
+	sm->next = cm->sublist;
+	cm->sublist = sm;
+	cm->subcount++;
+	return 0;
+}
+
+int cmesh_remove_submesh(struct cmesh *cm, int idx)
+{
+	struct submesh dummy;
+	struct submesh *prev, *sm;
+
+	if(idx >= cm->subcount) {
+		return -1;
+	}
+
+	dummy.next = cm->sublist;
+	prev = &dummy;
+
+	while(prev->next && idx-- > 0) {
+		prev = prev->next;
+	}
+
+	if(!(sm = prev->next)) return -1;
+
+	prev->next = sm->next;
+	free(sm->name);
+	free(sm);
+
+	cm->subcount--;
+	assert(cm->subcount >= 0);
+
+	cm->sublist = dummy.next;
+	return 0;
+}
+
+int cmesh_find_submesh(struct cmesh *cm, const char *name)
+{
+	int idx = 0;
+	struct submesh *sm = cm->sublist;
+	while(sm) {
+		if(strcmp(sm->name, name) == 0) {
+			assert(idx <= cm->subcount);
+			return idx;
+		}
+		idx++;
+		sm = sm->next;
+	}
+	return -1;
+}
+
+int cmesh_submesh_count(struct cmesh *cm)
+{
+	return cm->subcount;
+}
+
+static struct submesh *get_submesh(struct cmesh *m, int idx)
+{
+	struct submesh *sm = m->sublist;
+	while(sm && --idx >= 0) {
+		sm = sm->next;
+	}
+	return sm;
+}
+
+int cmesh_clone_submesh(struct cmesh *cmdest, struct cmesh *cm, int subidx)
+{
+	struct submesh *sub;
+
+	if(!(sub = get_submesh(cm, subidx))) {
+		return -1;
+	}
+	return clone(cmdest, cm, sub);
+}
+
+
+/* assemble a complete vertex by adding all the useful attributes */
+int cmesh_vertex(struct cmesh *cm, float x, float y, float z)
+{
+	int i, j;
+
+	cgm_wcons(cm->cur_val + CMESH_ATTR_VERTEX, x, y, z, 1.0f);
+	cm->vattr[CMESH_ATTR_VERTEX].data_valid = 1;
+	cm->vattr[CMESH_ATTR_VERTEX].nelem = 3;
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		if(cm->vattr[i].data_valid) {
+			int newsz = cm->vattr[i].count + cm->vattr[i].nelem;
+			float *tmp = realloc(cm->vattr[i].data, newsz * sizeof *tmp);
+			if(!tmp) return -1;
+			tmp += cm->vattr[i].count;
+
+			cm->vattr[i].data = tmp;
+			cm->vattr[i].count = newsz;
+
+			for(j=0; j<cm->vattr[i].nelem; j++) {
+				*tmp++ = *(&cm->cur_val[i].x + j);
+			}
+		}
+		cm->vattr[i].vbo_valid = 0;
+		cm->vattr[i].data_valid = 1;
+	}
+
+	if(cm->idata_valid) {
+		free(cm->idata);
+		cm->idata = 0;
+		cm->icount = 0;
+	}
+	cm->ibo_valid = cm->idata_valid = 0;
+	return 0;
+}
+
+void cmesh_normal(struct cmesh *cm, float nx, float ny, float nz)
+{
+	cgm_wcons(cm->cur_val + CMESH_ATTR_NORMAL, nx, ny, nz, 1.0f);
+	cm->vattr[CMESH_ATTR_NORMAL].nelem = 3;
+}
+
+void cmesh_tangent(struct cmesh *cm, float tx, float ty, float tz)
+{
+	cgm_wcons(cm->cur_val + CMESH_ATTR_TANGENT, tx, ty, tz, 1.0f);
+	cm->vattr[CMESH_ATTR_TANGENT].nelem = 3;
+}
+
+void cmesh_texcoord(struct cmesh *cm, float u, float v, float w)
+{
+	cgm_wcons(cm->cur_val + CMESH_ATTR_TEXCOORD, u, v, w, 1.0f);
+	cm->vattr[CMESH_ATTR_TEXCOORD].nelem = 3;
+}
+
+void cmesh_boneweights(struct cmesh *cm, float w1, float w2, float w3, float w4)
+{
+	cgm_wcons(cm->cur_val + CMESH_ATTR_BONEWEIGHTS, w1, w2, w3, w4);
+	cm->vattr[CMESH_ATTR_BONEWEIGHTS].nelem = 4;
+}
+
+void cmesh_boneidx(struct cmesh *cm, int idx1, int idx2, int idx3, int idx4)
+{
+	cgm_wcons(cm->cur_val + CMESH_ATTR_BONEIDX, idx1, idx2, idx3, idx4);
+	cm->vattr[CMESH_ATTR_BONEIDX].nelem = 4;
+}
+
+static float *get_vec4(struct cmesh *cm, int attr, int idx, cgm_vec4 *res)
+{
+	int i;
+	float *sptr, *dptr;
+	cgm_wcons(res, 0, 0, 0, 1);
+	if(!(sptr = cmesh_attrib_at(cm, attr, idx))) {
+		return 0;
+	}
+	dptr = &res->x;
+
+	for(i=0; i<cm->vattr[attr].nelem; i++) {
+		*dptr++ = sptr[i];
+	}
+	return sptr;
+}
+
+static float *get_vec3(struct cmesh *cm, int attr, int idx, cgm_vec3 *res)
+{
+	int i;
+	float *sptr, *dptr;
+	cgm_vcons(res, 0, 0, 0);
+	if(!(sptr = cmesh_attrib_at(cm, attr, idx))) {
+		return 0;
+	}
+	dptr = &res->x;
+
+	for(i=0; i<cm->vattr[attr].nelem; i++) {
+		*dptr++ = sptr[i];
+	}
+	return sptr;
+}
+
+/* dir_xform can be null, in which case it's calculated from xform */
+void cmesh_apply_xform(struct cmesh *cm, float *xform, float *dir_xform)
+{
+	unsigned int i;
+	int j;
+	cgm_vec4 v;
+	cgm_vec3 n, t;
+	float *vptr;
+
+	for(i=0; i<cm->nverts; i++) {
+		if(!(vptr = get_vec4(cm, CMESH_ATTR_VERTEX, i, &v))) {
+			return;
+		}
+		cgm_wmul_m4v4(&v, xform);
+		for(j=0; j<cm->vattr[CMESH_ATTR_VERTEX].nelem; j++) {
+			*vptr++ = (&v.x)[j];
+		}
+
+		if(cmesh_has_attrib(cm, CMESH_ATTR_NORMAL)) {
+			if((vptr = get_vec3(cm, CMESH_ATTR_NORMAL, i, &n))) {
+				cgm_vmul_m3v3(&n, dir_xform);
+				for(j=0; j<cm->vattr[CMESH_ATTR_NORMAL].nelem; j++) {
+					*vptr++ = (&n.x)[j];
+				}
+			}
+		}
+		if(cmesh_has_attrib(cm, CMESH_ATTR_TANGENT)) {
+			if((vptr = get_vec3(cm, CMESH_ATTR_TANGENT, i, &t))) {
+				cgm_vmul_m3v3(&t, dir_xform);
+				for(j=0; j<cm->vattr[CMESH_ATTR_TANGENT].nelem; j++) {
+					*vptr++ = (&t.x)[j];
+				}
+			}
+		}
+	}
+}
+
+void cmesh_flip(struct cmesh *cm)
+{
+	cmesh_flip_faces(cm);
+	cmesh_flip_normals(cm);
+}
+
+void cmesh_flip_faces(struct cmesh *cm)
+{
+	int i, j, idxnum, vnum, nelem;
+	unsigned int *indices;
+	float *verts, *vptr;
+
+	if(cmesh_indexed(cm)) {
+		if(!(indices = cmesh_index(cm))) {
+			return;
+		}
+		idxnum = cmesh_index_count(cm);
+		for(i=0; i<idxnum; i+=3) {
+			unsigned int tmp = indices[i + 2];
+			indices[i + 2] = indices[i + 1];
+			indices[i + 1] = tmp;
+		}
+	} else {
+		if(!(verts = cmesh_attrib(cm, CMESH_ATTR_VERTEX))) {
+			return;
+		}
+		vnum = cmesh_attrib_count(cm, CMESH_ATTR_VERTEX);
+		nelem = cm->vattr[CMESH_ATTR_VERTEX].nelem;
+		for(i=0; i<vnum; i+=3) {
+			for(j=0; j<nelem; j++) {
+				vptr = verts + (i + 1) * nelem + j;
+				float tmp = vptr[nelem];
+				vptr[nelem] = vptr[0];
+				vptr[0] = tmp;
+			}
+		}
+	}
+}
+void cmesh_flip_normals(struct cmesh *cm)
+{
+	int i, num;
+	float *nptr = cmesh_attrib(cm, CMESH_ATTR_NORMAL);
+	if(!nptr) return;
+
+	num = cm->nverts * cm->vattr[CMESH_ATTR_NORMAL].nelem;
+	for(i=0; i<num; i++) {
+		*nptr = -*nptr;
+		nptr++;
+	}
+}
+
+int cmesh_explode(struct cmesh *cm)
+{
+	int i, j, k, idxnum, nnverts;
+	unsigned int *indices;
+
+	if(!cmesh_indexed(cm)) return 0;
+
+	indices = cmesh_index(cm);
+	assert(indices);
+
+	idxnum = cmesh_index_count(cm);
+	nnverts = idxnum;
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		const float *srcbuf;
+		float *tmpbuf, *dstptr;
+
+		if(!cmesh_has_attrib(cm, i)) continue;
+
+		srcbuf = cmesh_attrib(cm, i);
+		if(!(tmpbuf = malloc(nnverts * cm->vattr[i].nelem * sizeof(float)))) {
+			return -1;
+		}
+		dstptr = tmpbuf;
+
+		for(j=0; j<idxnum; j++) {
+			unsigned int idx = indices[j];
+			const float *srcptr = srcbuf + idx * cm->vattr[i].nelem;
+
+			for(k=0; k<cm->vattr[i].nelem; k++) {
+				*dstptr++ = *srcptr++;
+			}
+		}
+
+		free(cm->vattr[i].data);
+		cm->vattr[i].data = tmpbuf;
+		cm->vattr[i].count = nnverts * cm->vattr[i].nelem;
+		cm->vattr[i].data_valid = 1;
+	}
+
+	cm->ibo_valid = 0;
+	cm->idata_valid = 0;
+	free(cm->idata);
+	cm->idata = 0;
+	cm->icount = 0;
+
+	cm->nverts = nnverts;
+	cm->nfaces = idxnum / 3;
+	return 0;
+}
+
+void cmesh_calc_face_normals(struct cmesh *cm)
+{
+	/* TODO */
+}
+
+static int pre_draw(struct cmesh *cm)
+{
+	int i, loc, cur_sdr;
+
+	glGetIntegerv(GL_CURRENT_PROGRAM, &cur_sdr);
+
+	update_buffers(cm);
+
+	if(!cm->vattr[CMESH_ATTR_VERTEX].vbo_valid) {
+		return -1;
+	}
+
+	if(cur_sdr && use_custom_sdr_attr) {
+		if(sdr_loc[CMESH_ATTR_VERTEX] == -1) {
+			return -1;
+		}
+
+		for(i=0; i<CMESH_NUM_ATTR; i++) {
+			loc = sdr_loc[i];
+			if(loc >= 0 && cm->vattr[i].vbo_valid) {
+				glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[i].vbo);
+				glVertexAttribPointer(loc, cm->vattr[i].nelem, GL_FLOAT, GL_FALSE, 0, 0);
+				glEnableVertexAttribArray(loc);
+			}
+		}
+	} else {
+#ifndef GL_ES_VERSION_2_0
+		glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[CMESH_ATTR_VERTEX].vbo);
+		glVertexPointer(cm->vattr[CMESH_ATTR_VERTEX].nelem, GL_FLOAT, 0, 0);
+		glEnableClientState(GL_VERTEX_ARRAY);
+
+		if(cm->vattr[CMESH_ATTR_NORMAL].vbo_valid) {
+			glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[CMESH_ATTR_NORMAL].vbo);
+			glNormalPointer(GL_FLOAT, 0, 0);
+			glEnableClientState(GL_NORMAL_ARRAY);
+		}
+		if(cm->vattr[CMESH_ATTR_TEXCOORD].vbo_valid) {
+			glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[CMESH_ATTR_TEXCOORD].vbo);
+			glTexCoordPointer(cm->vattr[CMESH_ATTR_TEXCOORD].nelem, GL_FLOAT, 0, 0);
+			glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+		}
+		if(cm->vattr[CMESH_ATTR_COLOR].vbo_valid) {
+			glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[CMESH_ATTR_COLOR].vbo);
+			glColorPointer(cm->vattr[CMESH_ATTR_COLOR].nelem, GL_FLOAT, 0, 0);
+			glEnableClientState(GL_COLOR_ARRAY);
+		}
+		if(cm->vattr[CMESH_ATTR_TEXCOORD2].vbo_valid) {
+			glClientActiveTexture(GL_TEXTURE1);
+			glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[CMESH_ATTR_TEXCOORD2].vbo);
+			glTexCoordPointer(cm->vattr[CMESH_ATTR_TEXCOORD2].nelem, GL_FLOAT, 0, 0);
+			glEnableClientState(GL_TEXTURE_COORD_ARRAY);
+			glClientActiveTexture(GL_TEXTURE0);
+		}
+#endif	/* GL_ES_VERSION_2_0 */
+	}
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	return cur_sdr;
+}
+
+void cmesh_draw(struct cmesh *cm)
+{
+	if(cm->ibo_valid) {
+		cmesh_draw_range(cm, 0, cm->nfaces * 3);
+	} else {
+		cmesh_draw_range(cm, 0, cm->nverts);
+	}
+}
+
+void cmesh_draw_range(struct cmesh *cm, int start, int count)
+{
+	int cur_sdr;
+
+	if((cur_sdr = pre_draw(cm)) == -1) {
+		return;
+	}
+
+	if(cm->ibo_valid) {
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cm->ibo);
+		glDrawElements(GL_TRIANGLES, count, GL_UNSIGNED_INT, (void*)(start * 4));
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+	} else {
+		glDrawArrays(GL_TRIANGLES, start, count);
+	}
+
+	post_draw(cm, cur_sdr);
+}
+
+void cmesh_draw_submesh(struct cmesh *cm, int subidx)
+{
+	struct submesh *sm = cm->sublist;
+
+	while(sm && subidx-- > 0) {
+		sm = sm->next;
+	}
+	if(!sm) return;
+
+	if(sm->icount) {
+		cmesh_draw_range(cm, sm->istart, sm->icount);
+	} else {
+		cmesh_draw_range(cm, sm->vstart, sm->vcount);
+	}
+}
+
+static void post_draw(struct cmesh *cm, int cur_sdr)
+{
+	int i;
+
+	if(cur_sdr && use_custom_sdr_attr) {
+		for(i=0; i<CMESH_NUM_ATTR; i++) {
+			int loc = sdr_loc[i];
+			if(loc >= 0 && cm->vattr[i].vbo_valid) {
+				glDisableVertexAttribArray(loc);
+			}
+		}
+	} else {
+#ifndef GL_ES_VERSION_2_0
+		glDisableClientState(GL_VERTEX_ARRAY);
+		if(cm->vattr[CMESH_ATTR_NORMAL].vbo_valid) {
+			glDisableClientState(GL_NORMAL_ARRAY);
+		}
+		if(cm->vattr[CMESH_ATTR_TEXCOORD].vbo_valid) {
+			glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+		}
+		if(cm->vattr[CMESH_ATTR_COLOR].vbo_valid) {
+			glDisableClientState(GL_COLOR_ARRAY);
+		}
+		if(cm->vattr[CMESH_ATTR_TEXCOORD2].vbo_valid) {
+			glClientActiveTexture(GL_TEXTURE1);
+			glDisableClientState(GL_TEXTURE_COORD_ARRAY);
+			glClientActiveTexture(GL_TEXTURE0);
+		}
+#endif	/* GL_ES_VERSION_2_0 */
+	}
+}
+
+void cmesh_draw_wire(struct cmesh *cm, float linesz)
+{
+	int cur_sdr, nfaces;
+
+	if((cur_sdr = pre_draw(cm)) == -1) {
+		return;
+	}
+	update_wire_ibo(cm);
+
+	nfaces = cmesh_poly_count(cm);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cm->wire_ibo);
+	glDrawElements(GL_LINES, nfaces * 6, GL_UNSIGNED_INT, 0);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+
+	post_draw(cm, cur_sdr);
+}
+
+void cmesh_draw_vertices(struct cmesh *cm, float ptsz)
+{
+	int cur_sdr;
+	if((cur_sdr = pre_draw(cm)) == -1) {
+		return;
+	}
+
+	glPushAttrib(GL_POINT_BIT);
+	glPointSize(ptsz);
+	glDrawArrays(GL_POINTS, 0, cm->nverts);
+	glPopAttrib();
+
+	post_draw(cm, cur_sdr);
+}
+
+void cmesh_draw_normals(struct cmesh *cm, float len)
+{
+#ifndef GL_ES_VERSION_2_0
+	int i, cur_sdr, vert_nelem, norm_nelem;
+	int loc = -1;
+	const float *varr, *norm;
+
+	varr = cmesh_attrib_ro(cm, CMESH_ATTR_VERTEX);
+	norm = cmesh_attrib_ro(cm, CMESH_ATTR_NORMAL);
+	if(!varr || !norm) return;
+
+	vert_nelem = cm->vattr[CMESH_ATTR_VERTEX].nelem;
+	norm_nelem = cm->vattr[CMESH_ATTR_NORMAL].nelem;
+
+	glGetIntegerv(GL_CURRENT_PROGRAM, &cur_sdr);
+	if(cur_sdr && use_custom_sdr_attr) {
+		if((loc = sdr_loc[CMESH_ATTR_VERTEX]) < 0) {
+			return;
+		}
+	}
+
+	glBegin(GL_LINES);
+	for(i=0; i<cm->nverts; i++) {
+		float x, y, z, endx, endy, endz;
+
+		x = varr[i * vert_nelem];
+		y = varr[i * vert_nelem + 1];
+		z = varr[i * vert_nelem + 2];
+		endx = x + norm[i * norm_nelem] * len;
+		endy = y + norm[i * norm_nelem + 1] * len;
+		endz = z + norm[i * norm_nelem + 2] * len;
+
+		if(loc == -1) {
+			glVertex3f(x, y, z);
+			glVertex3f(endx, endy, endz);
+		} else {
+			glVertexAttrib3f(loc, x, y, z);
+			glVertexAttrib3f(loc, endx, endy, endz);
+		}
+	}
+	glEnd();
+#endif	/* GL_ES_VERSION_2_0 */
+}
+
+void cmesh_draw_tangents(struct cmesh *cm, float len)
+{
+#ifndef GL_ES_VERSION_2_0
+	int i, cur_sdr, vert_nelem, tang_nelem;
+	int loc = -1;
+	const float *varr, *tang;
+
+	varr = cmesh_attrib_ro(cm, CMESH_ATTR_VERTEX);
+	tang = cmesh_attrib_ro(cm, CMESH_ATTR_TANGENT);
+	if(!varr || !tang) return;
+
+	vert_nelem = cm->vattr[CMESH_ATTR_VERTEX].nelem;
+	tang_nelem = cm->vattr[CMESH_ATTR_TANGENT].nelem;
+
+	glGetIntegerv(GL_CURRENT_PROGRAM, &cur_sdr);
+	if(cur_sdr && use_custom_sdr_attr) {
+		if((loc = sdr_loc[CMESH_ATTR_VERTEX]) < 0) {
+			return;
+		}
+	}
+
+	glBegin(GL_LINES);
+	for(i=0; i<cm->nverts; i++) {
+		float x, y, z, endx, endy, endz;
+
+		x = varr[i * vert_nelem];
+		y = varr[i * vert_nelem + 1];
+		z = varr[i * vert_nelem + 2];
+		endx = x + tang[i * tang_nelem] * len;
+		endy = y + tang[i * tang_nelem + 1] * len;
+		endz = z + tang[i * tang_nelem + 2] * len;
+
+		if(loc == -1) {
+			glVertex3f(x, y, z);
+			glVertex3f(endx, endy, endz);
+		} else {
+			glVertexAttrib3f(loc, x, y, z);
+			glVertexAttrib3f(loc, endx, endy, endz);
+		}
+	}
+	glEnd();
+#endif	/* GL_ES_VERSION_2_0 */
+}
+
+static void update_buffers(struct cmesh *cm)
+{
+	int i;
+
+	for(i=0; i<CMESH_NUM_ATTR; i++) {
+		if(cmesh_has_attrib(cm, i) && !cm->vattr[i].vbo_valid) {
+			glBindBuffer(GL_ARRAY_BUFFER, cm->vattr[i].vbo);
+			glBufferData(GL_ARRAY_BUFFER, cm->nverts * cm->vattr[i].nelem * sizeof(float),
+					cm->vattr[i].data, GL_STATIC_DRAW);
+			cm->vattr[i].vbo_valid = 1;
+		}
+	}
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+
+	if(cm->idata_valid && !cm->ibo_valid) {
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cm->ibo);
+		glBufferData(GL_ELEMENT_ARRAY_BUFFER, cm->nfaces * 3 * sizeof(unsigned int),
+				cm->idata, GL_STATIC_DRAW);
+		cm->ibo_valid = 1;
+		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+	}
+}
+
+static void update_wire_ibo(struct cmesh *cm)
+{
+	int i, num_faces;
+	unsigned int *wire_idxarr, *dest;
+
+	update_buffers(cm);
+
+	if(cm->wire_ibo_valid) return;
+
+	if(!cm->wire_ibo) {
+		glGenBuffers(1, &cm->wire_ibo);
+	}
+	num_faces = cmesh_poly_count(cm);
+
+	if(!(wire_idxarr = malloc(num_faces * 6 * sizeof *wire_idxarr))) {
+		return;
+	}
+	dest = wire_idxarr;
+
+	if(cm->ibo_valid) {
+		/* we're dealing with an indexed mesh */
+		const unsigned int *idxarr = cmesh_index_ro(cm);
+
+		for(i=0; i<num_faces; i++) {
+			*dest++ = idxarr[0];
+			*dest++ = idxarr[1];
+			*dest++ = idxarr[1];
+			*dest++ = idxarr[2];
+			*dest++ = idxarr[2];
+			*dest++ = idxarr[0];
+			idxarr += 3;
+		}
+	} else {
+		/* not an indexed mesh */
+		for(i=0; i<num_faces; i++) {
+			int vidx = i * 3;
+			*dest++ = vidx;
+			*dest++ = vidx + 1;
+			*dest++ = vidx + 1;
+			*dest++ = vidx + 2;
+			*dest++ = vidx + 2;
+			*dest++ = vidx;
+		}
+	}
+
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, cm->wire_ibo);
+	glBufferData(GL_ELEMENT_ARRAY_BUFFER, num_faces * 6 * sizeof(unsigned int),
+			wire_idxarr, GL_STATIC_DRAW);
+	free(wire_idxarr);
+	cm->wire_ibo_valid = 1;
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+}
+
+static void calc_aabb(struct cmesh *cm)
+{
+	int i, j;
+
+	if(!cmesh_attrib_ro(cm, CMESH_ATTR_VERTEX)) {
+		return;
+	}
+
+	cgm_vcons(&cm->aabb_min, FLT_MAX, FLT_MAX, FLT_MAX);
+	cgm_vcons(&cm->aabb_max, -FLT_MAX, -FLT_MAX, -FLT_MAX);
+
+	for(i=0; i<cm->nverts; i++) {
+		const float *v = cmesh_attrib_at_ro(cm, CMESH_ATTR_VERTEX, i);
+		for(j=0; j<3; j++) {
+			if(v[j] < (&cm->aabb_min.x)[j]) {
+				(&cm->aabb_min.x)[j] = v[j];
+			}
+			if(v[j] > (&cm->aabb_max.x)[j]) {
+				(&cm->aabb_max.x)[j] = v[j];
+			}
+		}
+	}
+	cm->aabb_valid = 1;
+}
+
+void cmesh_aabbox(struct cmesh *cm, cgm_vec3 *vmin, cgm_vec3 *vmax)
+{
+	if(!cm->aabb_valid) {
+		calc_aabb(cm);
+	}
+	*vmin = cm->aabb_min;
+	*vmax = cm->aabb_max;
+}
+
+static void calc_bsph(struct cmesh *cm)
+{
+	int i;
+	float s, dist_sq;
+
+	if(!cmesh_attrib_ro(cm, CMESH_ATTR_VERTEX)) {
+		return;
+	}
+
+	cgm_vcons(&cm->bsph_center, 0, 0, 0);
+
+	/* first find the center */
+	for(i=0; i<cm->nverts; i++) {
+		const float *v = cmesh_attrib_at_ro(cm, CMESH_ATTR_VERTEX, i);
+		cm->bsph_center.x += v[0];
+		cm->bsph_center.y += v[1];
+		cm->bsph_center.z += v[2];
+	}
+	s = 1.0f / (float)cm->nverts;
+	cm->bsph_center.x *= s;
+	cm->bsph_center.y *= s;
+	cm->bsph_center.z *= s;
+
+	cm->bsph_radius = 0.0f;
+	for(i=0; i<cm->nverts; i++) {
+		const cgm_vec3 *v = (const cgm_vec3*)cmesh_attrib_at_ro(cm, CMESH_ATTR_VERTEX, i);
+		if((dist_sq = cgm_vdist_sq(v, &cm->bsph_center)) > cm->bsph_radius) {
+			cm->bsph_radius = dist_sq;
+		}
+	}
+	cm->bsph_radius = sqrt(cm->bsph_radius);
+	cm->bsph_valid = 1;
+}
+
+float cmesh_bsphere(struct cmesh *cm, cgm_vec3 *center, float *rad)
+{
+	if(!cm->bsph_valid) {
+		calc_bsph(cm);
+	}
+	*center = cm->bsph_center;
+	*rad = cm->bsph_radius;
+	return cm->bsph_radius;
+}
+
+/* TODO */
+void cmesh_texcoord_apply_xform(struct cmesh *cm, float *xform);
+void cmesh_texcoord_gen_plane(struct cmesh *cm, cgm_vec3 *norm, cgm_vec3 *tang);
+void cmesh_texcoord_gen_box(struct cmesh *cm);
+void cmesh_texcoord_gen_cylinder(struct cmesh *cm);
+
+int cmesh_dump(struct cmesh *cm, const char *fname)
+{
+	FILE *fp = fopen(fname, "wb");
+	if(fp) {
+		int res = cmesh_dump_file(cm, fp);
+		fclose(fp);
+		return res;
+	}
+	return -1;
+}
+
+int cmesh_dump_file(struct cmesh *cm, FILE *fp)
+{
+	static const char *label[] = { "pos", "nor", "tan", "tex", "col", "bw", "bid", "tex2" };
+	static const char *elemfmt[] = { 0, " %s(%g)", " %s(%g, %g)", " %s(%g, %g, %g)", " %s(%g, %g, %g, %g)", 0 };
+	int i, j;
+
+	if(!cmesh_has_attrib(cm, CMESH_ATTR_VERTEX)) {
+		return -1;
+	}
+
+	fprintf(fp, "VERTEX ATTRIBUTES\n");
+
+	for(i=0; i<cm->nverts; i++) {
+		fprintf(fp, "%5u:", i);
+		for(j=0; j<CMESH_NUM_ATTR; j++) {
+			if(cmesh_has_attrib(cm, j)) {
+				const float *v = cmesh_attrib_at_ro(cm, j, i);
+				int nelem = cm->vattr[j].nelem;
+				fprintf(fp, elemfmt[nelem], label[j], v[0], nelem > 1 ? v[1] : 0.0f,
+						nelem > 2 ? v[2] : 0.0f, nelem > 3 ? v[3] : 0.0f);
+			}
+		}
+		fputc('\n', fp);
+	}
+
+	if(cmesh_indexed(cm)) {
+		const unsigned int *idx = cmesh_index_ro(cm);
+		int numidx = cmesh_index_count(cm);
+		int numtri = numidx / 3;
+		assert(numidx % 3 == 0);
+
+		fprintf(fp, "FACES\n");
+
+		for(i=0; i<numtri; i++) {
+			fprintf(fp, "%5d: %d %d %d\n", i, idx[0], idx[1], idx[2]);
+			idx += 3;
+		}
+	}
+	return 0;
+}
+
+int cmesh_dump_obj(struct cmesh *cm, const char *fname)
+{
+	FILE *fp = fopen(fname, "wb");
+	if(fp) {
+		int res = cmesh_dump_obj_file(cm, fp, 0);
+		fclose(fp);
+		return res;
+	}
+	return -1;
+}
+
+#define HAS_VN	1
+#define HAS_VT	2
+
+int cmesh_dump_obj_file(struct cmesh *cm, FILE *fp, int voffs)
+{
+	static const char *fmtstr[] = {" %u", " %u//%u", " %u/%u", " %u/%u/%u"};
+	int i, j, num, nelem;
+	unsigned int aflags = 0;
+
+	if(!cmesh_has_attrib(cm, CMESH_ATTR_VERTEX)) {
+		return -1;
+	}
+
+
+	nelem = cm->vattr[CMESH_ATTR_VERTEX].nelem;
+	if((num = cm->vattr[CMESH_ATTR_VERTEX].count) != cm->nverts * nelem) {
+		fprintf(stderr, "vertex array size (%d) != nverts (%d)\n", num, cm->nverts);
+	}
+	for(i=0; i<cm->nverts; i++) {
+		const float *v = cmesh_attrib_at_ro(cm, CMESH_ATTR_VERTEX, i);
+		fprintf(fp, "v %f %f %f\n", v[0], nelem > 1 ? v[1] : 0.0f, nelem > 2 ? v[2] : 0.0f);
+	}
+
+	if(cmesh_has_attrib(cm, CMESH_ATTR_NORMAL)) {
+		aflags |= HAS_VN;
+		nelem = cm->vattr[CMESH_ATTR_NORMAL].nelem;
+		if((num = cm->vattr[CMESH_ATTR_NORMAL].count) != cm->nverts * nelem) {
+			fprintf(stderr, "normal array size (%d) != nverts (%d)\n", num, cm->nverts);
+		}
+		for(i=0; i<cm->nverts; i++) {
+			const float *v = cmesh_attrib_at_ro(cm, CMESH_ATTR_NORMAL, i);
+			fprintf(fp, "vn %f %f %f\n", v[0], nelem > 1 ? v[1] : 0.0f, nelem > 2 ? v[2] : 0.0f);
+		}
+	}
+
+	if(cmesh_has_attrib(cm, CMESH_ATTR_TEXCOORD)) {
+		aflags |= HAS_VT;
+		nelem = cm->vattr[CMESH_ATTR_TEXCOORD].nelem;
+		if((num = cm->vattr[CMESH_ATTR_TEXCOORD].count) != cm->nverts * nelem) {
+			fprintf(stderr, "texcoord array size (%d) != nverts (%d)\n", num, cm->nverts);
+		}
+		for(i=0; i<cm->nverts; i++) {
+			const float *v = cmesh_attrib_at_ro(cm, CMESH_ATTR_TEXCOORD, i);
+			fprintf(fp, "vt %f %f\n", v[0], nelem > 1 ? v[1] : 0.0f);
+		}
+	}
+
+	if(cmesh_indexed(cm)) {
+		const unsigned int *idxptr = cmesh_index_ro(cm);
+		int numidx = cmesh_index_count(cm);
+		int numtri = numidx / 3;
+		assert(numidx % 3 == 0);
+
+		for(i=0; i<numtri; i++) {
+			fputc('f', fp);
+			for(j=0; j<3; j++) {
+				unsigned int idx = *idxptr++ + 1 + voffs;
+				fprintf(fp, fmtstr[aflags], idx, idx, idx);
+			}
+			fputc('\n', fp);
+		}
+	} else {
+		int numtri = cm->nverts / 3;
+		unsigned int idx = 1 + voffs;
+		for(i=0; i<numtri; i++) {
+			fputc('f', fp);
+			for(j=0; j<3; j++) {
+				fprintf(fp, fmtstr[aflags], idx, idx, idx);
+				++idx;
+			}
+			fputc('\n', fp);
+		}
+	}
+	return 0;
+}