viewer.c.md 20 KB
This is the old version of the viewer. It does generate a vertex buffer only if the model is animated (simply because you can't animate a mesh without one), but even then it uses direct OpenGL commands. This is not as effective as the current version, but I kept this too because the way how it displays faces is more readable and helps understanding M3D structures better.
/*
* m3dview/viewer.c
*
* Copyright (C) 2019 bzt (bztsrc@gitlab)
*
* Permission is hereby granted, free of charge, to any person
* obtaining a copy of this software and associated documentation
* files (the "Software"), to deal in the Software without
* restriction, including without limitation the rights to use, copy,
* modify, merge, publish, distribute, sublicense, and/or sell copies
* of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be
* included in all copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
* HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY,
* WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
* DEALINGS IN THE SOFTWARE.
*
* @brief simple portable Model 3D viewer - Simple OpenGL commands
* https://gitlab.com/bztsrc/model3d
*
*/
#include "viewer.h"
#include "font6.h"
#define M3D_IMPLEMENTATION
#define M3D_ASCII
#include <m3d.h>
#include <gl.h>
#include <unistd.h>
/* variables */
unsigned char *buff = NULL;
unsigned int size, actionid = 0, frame = -1U, fpsdivisor = 1, lastframe = 0;
char *wintitle = NULL, infostr[64];
m3d_t *model = NULL;
int screenw = 640, screenh = 480, doframe = 0;
int mousebtn = 0, mousemove = 0, mousex = 0, mousey = 0;
float mindist = 1, maxdist = 25, distance = 5.5, pitch = 0/*-35.264*/, yaw = 0/*45*/;
float light_position[4] = { -1, 2, 2, 0 }, light_color[4] = { 1, 1, 0.5, 1 }, shadow_color[4] = { 0, 0, 0, 0 };
unsigned int numvbo = 0, numtexture, texture[32];
m3dv_t *vbo = NULL;
unsigned char checker_data[4*128*128];
/**
* File reader callback for the M3D SDK, also used to load the model
*/
unsigned char *readfile(char *fn, unsigned int *size)
{
FILE *f;
unsigned char *ret = NULL;
*size = 0;
f = fopen(fn, "rb");
if(f) {
fseek(f, 0L, SEEK_END);
*size = (unsigned int)ftell(f);
fseek(f, 0L, SEEK_SET);
ret = (unsigned char*)malloc(*size + 1);
if(ret) {
fread(ret, *size, 1, f);
ret[*size] = 0;
} else
*size = 0;
fclose(f);
}
return ret;
}
/**
* Parse command line and load a model
*/
void load(int argc, char **argv)
{
/* check arguments */
if(argc < 2) {
printf("Model 3D Viewer by bzt Copyright (C) 2019 MIT license\n\n"
"./m3dview <m3d file>"
#ifdef PREVIEW
" [out.png]"
#endif
"\n\n");
exit(0);
}
/* read the file */
buff = readfile(argv[1], &size);
if(!buff) error("unable to load model file");
/* decode bit-chunk into in-memory C structures */
model = m3d_load(buff, readfile, free, NULL);
if(!model) error("unable to parse model");
/* set up window title */
wintitle = (char*)malloc(strlen(model->name) + strlen(model->license) + 32);
if(!wintitle) error("unable to allocate memory");
strcpy(wintitle, "Model 3D Viewer: ");
strcat(wintitle, model->name);
if(model->license[0]) {
strcat(wintitle, " (");
strcat(wintitle, model->license);
strcat(wintitle, ")");
}
sprintf(infostr, "%d triangles, %d vertices (%d bit), %d actions",
model->numface, model->numvertex, model->vc_s << 3, model->numaction);
}
/**
* Multiply a vertex with a transformation matrix
*/
void vec3_mul_mat4(m3dv_t *out, m3dv_t *v, float *mat)
{
out->x = mat[ 0] * v->x + mat[ 1] * v->y + mat[ 2] * v->z + mat[ 3];
out->y = mat[ 4] * v->x + mat[ 5] * v->y + mat[ 6] * v->z + mat[ 7];
out->z = mat[ 8] * v->x + mat[ 9] * v->y + mat[10] * v->z + mat[11];
}
/**
* Convert a standard uint32_t color into OpenGL color
*/
void set_color(uint32_t c, float *f) {
if(!c) {
f[0] = f[1] = f[2] = 0.0; f[3] = 1.0;
} else {
f[3] = ((float)((c >> 24)&0xff)) / 255;
#ifndef PREVIEW
f[2] = ((float)((c >> 16)&0xff)) / 255;
f[1] = ((float)((c >> 8)&0xff)) / 255;
f[0] = ((float)((c >> 0)&0xff)) / 255;
#else
f[2] = ((float)((c >> 16)&0xff)) / 256;
f[1] = ((float)((c >> 8)&0xff)) / 256;
f[0] = ((float)((c >> 0)&0xff)) / 256;
#endif
}
}
/**
* Set material to use.
*/
void set_material(unsigned int mi)
{
unsigned int i, t;
float color[4];
m3dm_t *m;
if(mi == -1U || mi >= model->nummaterial) return;
m = &model->material[mi];
glEnd();
/* reset GL material */
glDisable(GL_TEXTURE_2D);
glColor4f(0.5, 0.3, 0.1, 1);
set_color(0, (float*)&color);
glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, (GLfloat*)&color);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, (GLfloat*)&color);
glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, (GLfloat*)&color);
glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, 0.0);
/* update with what we have in this new material */
for(i = 0; i < m->numprop; i++) {
switch(m->prop[i].type) {
case m3dp_Kd:
set_color(m->prop[i].value.color, (float*)&color);
glColor4fv((GLfloat*)&color);
break;
case m3dp_Ka:
set_color(m->prop[i].value.color, (float*)&color);
glMaterialfv(GL_FRONT_AND_BACK, GL_AMBIENT, (GLfloat*)&color);
break;
case m3dp_Ks:
set_color(m->prop[i].value.color, (float*)&color);
glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, (GLfloat*)&color);
break;
case m3dp_Ke:
set_color(m->prop[i].value.color, (float*)&color);
glMaterialfv(GL_FRONT_AND_BACK, GL_EMISSION, (GLfloat*)&color);
break;
case m3dp_Ns:
glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, m->prop[i].value.fnum);
break;
case m3dp_map_Kd:
if(numtexture) {
t = m->prop[i].value.textureid < numtexture ? m->prop[i].value.textureid + 1 : 0;
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, texture[t]);
}
break;
}
}
glBegin(GL_TRIANGLES);
return;
}
/**
* Set FPS divisor for animation debugging
*/
void fpsdiv(int idx)
{
switch(idx) {
case 1: fpsdivisor = 2; break;
case 2: fpsdivisor = 3; break;
case 3: fpsdivisor = 5; break;
case 4: fpsdivisor = 10; break;
case 5: fpsdivisor = 15; break;
case 6: fpsdivisor = 20; break;
case 7: fpsdivisor = 25; break;
case 8: fpsdivisor = 30; break;
case 9: fpsdivisor = 60; break;
default: fpsdivisor = 1; break;
}
}
/**
* Switch to next frame
*/
void nextframe(void)
{
doframe = 0; frame++;
continous();
}
/**
* Switch to previous frame
*/
void prevframe(void)
{
doframe = 0; frame--;
continous();
}
/**
* Toggle continous playback
*/
void continous(void)
{
char *title, *name;
doframe ^= 1;
if(actionid < model->numaction) {
if(frame == -1U) frame = model->action[actionid].numframe - 1;
if(frame > model->action[actionid].numframe - 1) frame = 0;
} else
frame = 0;
name = doframe ? (actionid < model->numaction ? model->action[actionid].name : "(bind-pose)") : model->name;
title = (char*)malloc(strlen(name) + 64);
if(title) {
if(doframe)
sprintf(title, "Model 3D Viewer: %s (frame %4d / %4d)", name,
actionid < model->numaction ? frame + 1 : 1,
actionid < model->numaction ? model->action[actionid].numframe : 1);
else
sprintf(title, "Model 3D Viewer: %s", model->name);
set_title(title);
free(title);
}
}
/**
* Zoom in
*/
void zoomin(void)
{
distance -= 0.01 * distance;
if(distance < 0.000001) distance = 0.000001;
}
/**
* Zoom out
*/
void zoomout(void)
{
distance += 0.01 * distance;
if(distance > 100000) distance = 100000;
}
/**
* Print an UTF-8 string
*/
void glPrint(char *s)
{
unsigned int c;
while(*s) {
if((*s & 128) != 0) {
if(!(*s & 32)) { c = ((*s & 0x1F)<<6)|(*(s+1) & 0x3F); s++; } else
if(!(*s & 16)) { c = ((*s & 0xF)<<12)|((*(s+1) & 0x3F)<<6)|(*(s+2) & 0x3F); s += 2; } else
if(!(*s & 8)) { c = ((*s & 0x7)<<18)|((*(s+1) & 0x3F)<<12)|((*(s+2) & 0x3F)<<6)|(*(s+3) & 0x3F); *s += 3; }
else c = 0;
} else c = *s;
s++;
if(c >= (unsigned int)(sizeof(font)/sizeof(font[0]))) c = 0;
glBitmap(FONT_WIDTH, FONT_HEIGHT, 0, 0, (float)FONT_WIDTH, 0.0, ((unsigned char*)&font + c * FONT_HEIGHT));
}
}
/**
* Set up OpenGL context
*/
void setupgl(void)
{
unsigned int i, j, k;
glEnable(GL_MULTISAMPLE);
glEnable(GL_NORMALIZE);
glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
glClearColor(0.4, 0.4, 0.4, 1.0);
glShadeModel(GL_SMOOTH);
glFrontFace(GL_CCW);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
glLightfv(GL_LIGHT0, GL_POSITION, light_position);
glLightfv(GL_LIGHT0, GL_SPECULAR, light_color);
glLightfv(GL_LIGHT0, GL_AMBIENT, shadow_color);
glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
glLightModeli(GL_LIGHT_MODEL_TWO_SIDE, GL_TRUE);
glViewport(0, 0, screenw, screenh);
/* set up vbo array */
if(model->numface && model->numbone && model->numskin && model->numaction) {
numvbo = model->numface * 3 /* triangle */ * 2 /* vertex + normal */;
vbo = (m3dv_t*)malloc(numvbo * sizeof(m3dv_t));
if(!vbo) error("unable to allocate memory");
/* create separate vertex records in vbo, because animation may change differently
* for different triangles that share vertex coordinates */
for(i = k = 0; i < model->numface; i++)
for(j = 0; j < 3; j++, k += 2) {
memcpy(&vbo[k+0], &model->vertex[model->face[i].vertex[j]], sizeof(m3dv_t));
memcpy(&vbo[k+1], &model->vertex[model->face[i].normal[j]], sizeof(m3dv_t));
/* to avoid allocating extra memory, we store the original vertex id in vbo color */
vbo[k+0].color = model->face[i].vertex[j];
vbo[k+1].color = model->face[i].normal[j];
/* copy vertex skinid to normal, normals usually are skin neutral in models */
vbo[k+1].skinid = vbo[k+0].skinid;
}
}
/* set up GL textures */
glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, (GLint*)&numtexture);
if(numtexture > 31) numtexture = 31;
if(numtexture < 1) return;
memset(texture, 0, sizeof(texture));
glGenTextures(numtexture, (GLuint*)&texture);
for (j = k = 0; j < 128; j++)
for (i = 0; i < 128; i++) {
checker_data[k++] = 127 + ((((i>>5) & 1) ^ ((j>>5) & 1)) << 5);
checker_data[k++] = 85;
checker_data[k++] = 25;
checker_data[k++] = 255;
}
glBindTexture(GL_TEXTURE_2D, texture[0]);
glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 128, 128, 0, GL_RGBA, GL_UNSIGNED_BYTE, checker_data);
/* add textures from model */
if(model->numtexture) {
for(i = 0; i < numtexture && i < model->numtexture; i++) {
if(!model->texture[i].w || !model->texture[i].h || !model->texture[i].d) {
fprintf(stderr, "m3dview: unable to load texture '%s'\n", model->texture[i].name);
texture[1 + i] = texture[0];
continue;
}
glBindTexture(GL_TEXTURE_2D, texture[1 + i]);
glTexParameteri(GL_TEXTURE_2D, GL_GENERATE_MIPMAP, GL_TRUE);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR_MIPMAP_LINEAR);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, model->texture[i].w, model->texture[i].h, 0, GL_RGBA, GL_UNSIGNED_BYTE,
model->texture[i].d);
}
}
}
/**
* Animate the mesh
*/
void animate_model(unsigned int msec)
{
unsigned int i, j, s;
m3db_t *animpose;
m3dv_t tmp1, tmp2;
if(actionid < model->numaction && doframe) {
/* if we are frame debugging, use the exact timestamp of the frame as msec */
msec = model->action[actionid].frame[frame].msec;
} else
/* otherwise modify by the debugging fps divisor (is 1 by default) */
msec /= fpsdivisor;
/* don't regenerate if we have the same timestamp as last time */
if(msec == lastframe) return;
lastframe = msec;
/* get the animation-pose skeleton*/
animpose = m3d_pose(model, actionid, msec);
/* convert mesh vertices from bind-pose into animation-pose */
for(i = 0; i < numvbo; i++) {
s = vbo[i].skinid;
if(s != -1U) {
vbo[i].x = vbo[i].y = vbo[i].z = 0;
for(j = 0; j < M3D_NUMBONE && model->skin[s].weight[j] > 0.0; j++) {
/* transfer from bind-pose model-space into bone-local space */
vec3_mul_mat4(&tmp1, &model->vertex[vbo[i].color], (float*)&model->bone[ model->skin[s].boneid[j] ].mat4);
/* transfer from bone-local space into animation-pose model-space */
vec3_mul_mat4(&tmp2, &tmp1, (float*)&animpose[ model->skin[s].boneid[j] ].mat4);
/* adjust with weight and accumulate */
vbo[i].x += tmp2.x * model->skin[s].weight[j];
vbo[i].y += tmp2.y * model->skin[s].weight[j];
vbo[i].z += tmp2.z * model->skin[s].weight[j];
}
}
}
free(animpose);
}
/**
* Display the model
*/
void display(unsigned int msec)
{
unsigned int i, j, k, mi = -1U, c = 0, lc = 0;
m3dv_t *v;
float color[4] = { 0, 0, 0, 1 }, fov;
/* handle model rotation */
if(mousemove) {
yaw -= mousex * 0.3;
pitch -= mousey * 0.2;
if (pitch < -90) pitch = -90;
if (pitch > 90) pitch = 90;
if (yaw < 0) yaw += 360;
if (yaw > 360) yaw -= 360;
mousemove = 0;
}
/* switch action to animate */
if(actionid == -1U) actionid = model->numaction;
else if((unsigned int)actionid > model->numaction) actionid = 0;
/* display model */
#ifdef PREVIEW
if(!msec)
glClearColor(1.0, 1.0, 1.0, 1.0);
#endif
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
fov = 0.221694 * (mindist/5);
glFrustum(-fov, fov, -fov, fov, mindist/5, maxdist*5);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glEnable(GL_DEPTH_TEST);
glTranslatef(0, 0, -distance*1.1);
glRotatef(-pitch, 1, 0, 0);
glRotatef(-yaw, 0, 1, 0);
glTranslatef(0, 0, 0);
glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
/* draw the coordinate system */
if(msec) {
glDisable(GL_LIGHTING);
glBegin(GL_LINES);
glColor4f(1, 0, 0, 1);
glVertex3f(0, 0, 0); glVertex3f(1.001, 0, 0);
glColor4f(0.5, 0.4, 0.4, 1);
glVertex3f(0, 0, 0); glVertex3f(-1.001, 0, 0);
glColor4f(0, 1, 0, 1);
glVertex3f(0, 0, 0); glVertex3f(0, 1.001, 0);
glColor4f(0.4, 0.5, 0.4, 1);
glVertex3f(0, 0, 0); glVertex3f(0, -1.001, 0);
glColor4f(0, 0, 1, 1);
glVertex3f(0, 0, 0); glVertex3f(0, 0, 1.001);
glColor4f(0.4, 0.4, 0.5, 1);
glVertex3f(0, 0, 0); glVertex3f(0, 0, -1.001);
glEnd();
}
glColor4f(0.5, 0.3, 0.1, 1);
/* draw the mesh */
glEnable(GL_COLOR_MATERIAL);
glEnable(GL_LIGHTING);
glEnable(GL_LIGHT0);
if(model->numtexture) {
glEnable(GL_TEXTURE_2D);
glBindTexture(GL_TEXTURE_2D, texture[0]);
}
glAlphaFunc(GL_GREATER, 0.2);
glEnable(GL_ALPHA_TEST);
glEnable(GL_BLEND);
/* animate the mesh if we have a vertex buffer object */
if(vbo)
animate_model(msec);
/* you should use glDrawArrays here. this is a simple, most portable viewer */
glBegin(GL_TRIANGLES);
for(i = k = 0; i < model->numface; i++) {
/* if material changed */
if(mi != model->face[i].materialid) {
mi = model->face[i].materialid;
set_material(mi);
lc = 0;
}
/* we have triangles */
for(j = 0; j < 3; j++, k += 2) {
/* get normals and color */
if(vbo) {
v = &vbo[k+1];
glNormal3f(v->x, v->y, v->z);
v = &vbo[k];
/* so save space, we've stored the original vertex id in vbo colors */
c = model->vertex[vbo[k].color].color;
} else {
v = &model->vertex[model->face[i].normal[j]];
glNormal3f(v->x, v->y, v->z);
v = &model->vertex[model->face[i].vertex[j]];
c = v->color;
}
/* if there's no material and color changed */
if(mi == -1U && c != lc) {
lc = c;
set_color(c, (float*)&color);
glColor4fv((GLfloat*)&color);
}
if(model->face[i].texcoord[j] != -1U) {
glTexCoord2f(model->tmap[model->face[i].texcoord[j]].u, 1.0 - model->tmap[model->face[i].texcoord[j]].v);
}
/* add the vertex */
glVertex3f(v->x, v->y, v->z);
}
}
glEnd();
glDisable(GL_BLEND);
glDisable(GL_ALPHA_TEST);
glDisable(GL_TEXTURE_2D);
glDisable(GL_LIGHTING);
glDisable(GL_COLOR_MATERIAL);
glDisable(GL_DEPTH_TEST);
/* on screen text */
if(msec) {
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0, screenw, screenh, 0, -1, 1);
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glColor4f(1, 1, 1, 1);
glPushClientAttrib( GL_CLIENT_PIXEL_STORE_BIT );
glPixelStorei( GL_UNPACK_SWAP_BYTES, GL_FALSE );
glPixelStorei( GL_UNPACK_LSB_FIRST, GL_FALSE );
glPixelStorei( GL_UNPACK_ROW_LENGTH, 0 );
glPixelStorei( GL_UNPACK_SKIP_ROWS, 0 );
glPixelStorei( GL_UNPACK_SKIP_PIXELS, 0 );
glPixelStorei( GL_UNPACK_ALIGNMENT, 1 );
glRasterPos2f(0.0, (float)FONT_HEIGHT);
glPrint(model->name);
glPrint(" (");
glPrint(model->license[0] ? model->license : "no license");
glPrint(", ");
glPrint(model->author[0] ? model->author : "no author");
glPrint(")");
glRasterPos2f(0.0, (float)(FONT_HEIGHT*2));
glPrint(infostr);
if(model->numaction) {
glPrint(", current: ");
glPrint(actionid < model->numaction ? model->action[actionid].name : "(bind-pose)");
}
glPopClientAttrib();
}
}
/**
* Print an error message and quit
*/
void error(char *msg)
{
fprintf(stderr, "m3dview: %s\n", msg);
cleanup();
exit(1);
}
/**
* Clean up on exit
*/
void cleanup()
{
if(model) m3d_free(model);
if(vbo) free(vbo);
if(buff) free(buff);
}