Add array data struct

Add bmesh define
Add vec3
Add camera control
Add draw x,z axis

src/array.c

@@ -0,0 +1,54 @@
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "array.h"
+
+struct array {
+  int nodeSize;
+  int capacity;
+  int length;
+  char *nodes;
+};
+
+array *arrayCreate(int nodeSize) {
+  array *arr = (array *)calloc(1, sizeof(array));
+  if (!arr) {
+    fprintf(stderr, "%s:Insufficient memory.\n", __FUNCTION__);
+    return 0;
+  }
+  arr->nodeSize = nodeSize;
+  return arr;
+}
+
+int arraySetLength(array *arr, int length) {
+  if (length > arr->capacity) {
+    int newCapacity = (arr->capacity + 1) * 2;
+    char *newNodes = (char *)realloc(arr->nodes, arr->nodeSize * newCapacity);
+    if (!newNodes) {
+      fprintf(stderr, "%s:Insufficient memory.\n", __FUNCTION__);
+      return -1;
+    }
+    arr->capacity = newCapacity;
+    arr->nodes = newNodes;
+  }
+  arr->length = length;
+  return 0;
+}
+
+void *arrayGetItem(array *arr, int index) {
+  if (index >= arr->length) {
+    return 0;
+  }
+  return arr->nodes + arr->nodeSize * index;
+}
+
+int arrayGetLength(array *arr) {
+  return arr->length;
+}
+
+void arrayDestroy(array *arr) {
+  if (arr) {
+    free(arr->nodes);
+    free(arr);
+  }
+}

src/array.h

@@ -0,0 +1,20 @@
+#ifndef ARRAY_H
+#define ARRAY_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct array array;
+
+array *arrayCreate(int nodeSize);
+void *arrayGetItem(array *arr, int index);
+int arrayGetLength(array *arr);
+int arraySetLength(array *arr, int length);
+void arrayDestroy(array *arr);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/bmesh.c

@@ -0,0 +1,75 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include "bmesh.h"
+#include "array.h"
+
+struct bmesh {
+  array *nodeArray;
+  array *edgeArray;
+};
+
+bmesh *bmeshCreate(void) {
+  bmesh *bm = (bmesh *)calloc(1, sizeof(bmesh));
+  if (!bm) {
+    fprintf(stderr, "%s:Insufficient memory.\n", __FUNCTION__);
+    return 0;
+  }
+  bm->nodeArray = arrayCreate(sizeof(bmeshNode));
+  if (!bm->nodeArray) {
+    fprintf(stderr, "%s:arrayCreate bmeshNode failed.\n", __FUNCTION__);
+    bmeshDestroy(bm);
+    return 0;
+  }
+  bm->edgeArray = arrayCreate(sizeof(bmeshEdge));
+  if (!bm->edgeArray) {
+    fprintf(stderr, "%s:arrayCreate bmeshEdge failed.\n", __FUNCTION__);
+    bmeshDestroy(bm);
+    return 0;
+  }
+  return bm;
+}
+
+void bmeshDestroy(bmesh *bm) {
+  arrayDestroy(bm->nodeArray);
+  arrayDestroy(bm->edgeArray);
+  free(bm);
+}
+
+int bmeshGetNodeNum(bmesh *bm) {
+  return arrayGetLength(bm->nodeArray);
+}
+
+int bmeshGetEdgeNum(bmesh *bm) {
+  return arrayGetLength(bm->edgeArray);
+}
+
+bmeshNode *bmeshGetNode(bmesh *bm, int index) {
+  return (bmeshNode *)arrayGetItem(bm->nodeArray, index);
+}
+
+bmeshEdge *bmeshGetEdge(bmesh *bm, int index) {
+  return (bmeshEdge *)arrayGetItem(bm->edgeArray, index);
+}
+
+int bmeshAddNode(bmesh *bm, bmeshNode *node) {
+  int index = arrayGetLength(bm->nodeArray);
+  node->index = index;
+  if (0 != arraySetLength(bm->nodeArray, index + 1)) {
+    fprintf(stderr, "%s:arraySetLength failed.\n", __FUNCTION__);
+    return -1;
+  }
+  memcpy(arrayGetItem(bm->nodeArray, index), node, sizeof(bmeshNode));
+  return index;
+}
+
+int bmeshAddEdge(bmesh *bm, bmeshEdge *edge) {
+  int index = arrayGetLength(bm->edgeArray);
+  edge->index = index;
+  if (0 != arraySetLength(bm->edgeArray, index + 1)) {
+    fprintf(stderr, "%s:arraySetLength failed.\n", __FUNCTION__);
+    return -1;
+  }
+  memcpy(arrayGetItem(bm->edgeArray, index), edge, sizeof(bmeshEdge));
+  return index;
+}

src/bmesh.h

@@ -0,0 +1,43 @@
+#ifndef B_MESH_H
+#define B_MESH_H
+#include "vector3d.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef enum {
+  BMESH_NODE_FLAG_KEY = 0x00000001,
+  BMESH_NODE_FLAG_INBETWEEN = 0x00000002,
+  BMESH_NODE_FLAG_ROOT = 0x00000010,
+} bmeshNodeFlag;
+
+typedef struct bmesh bmesh;
+
+typedef struct {
+  int index;
+  vec3 position;
+  float radius;
+  unsigned int flag;
+} bmeshNode;
+
+typedef struct {
+  int index;
+  int firstNode;
+  int secondNode;
+} bmeshEdge;
+
+bmesh *bmeshCreate(void);
+void bmeshDestroy(bmesh *bm);
+int bmeshGetNodeNum(bmesh *bm);
+int bmeshGetEdgeNum(bmesh *bm);
+bmeshNode *bmeshGetNode(bmesh *bm, int index);
+bmeshEdge *bmeshGetEdge(bmesh *bm, int index);
+int bmeshAddNode(bmesh *bm, bmeshNode *node);
+int bmeshAddEdge(bmesh *bm, bmeshEdge *edge);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/draw.cpp

@@ -0,0 +1,223 @@
+#include <QtGui>
+#include <QtOpenGL>
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include "draw.h"
+
+/*
+ * This drawSphere function modified from [Jon Leech's implementation of sphere](ftp://ftp.ee.lbl.gov/sphere.c)
+ * Jeremy HU (huxingyi@msn.com) 2016/12/16
+*/
+
+#define XPLUS {  1,  0,  0 }  /*  X */
+#define XMIN  { -1,  0,  0 }  /* -X */
+#define YPLUS {  0,  1,  0 }  /*  Y */
+#define YMIN  {  0, -1,  0 }  /* -Y */
+#define ZPLUS {  0,  0,  1 }  /*  Z */
+#define ZMIN  {  0,  0, -1 }  /* -Z */
+
+static const triangle octahedron[] = {
+  {{XPLUS, ZPLUS, YPLUS}},
+  {{YPLUS, ZPLUS, XMIN}},
+  {{XMIN,  ZPLUS, YMIN}},
+  {{YMIN,  ZPLUS, XPLUS}},
+  {{XPLUS, YPLUS, ZMIN}},
+  {{YPLUS, XMIN,  ZMIN}},
+  {{XMIN,  YMIN,  ZMIN}},
+  {{YMIN,  XPLUS, ZMIN}},
+};
+
+static void subdivide(object *old, object *subdivided) {
+  int i;
+  for (i = 0; i < old->npoly; ++i) {
+    triangle *oldt = &old->poly[i];
+    triangle *newt = &subdivided->poly[i * 4];
+    vec3 a, b, c;
+
+    vec3Midpoint(&oldt->pt[0], &oldt->pt[2], &a);
+    vec3Midpoint(&oldt->pt[0], &oldt->pt[1], &b);
+    vec3Midpoint(&oldt->pt[1], &oldt->pt[2], &c);
+
+    vec3Normalize(&a);
+    vec3Normalize(&b);
+    vec3Normalize(&c);
+
+    newt->pt[0] = oldt->pt[0];
+    newt->pt[1] = b;
+    newt->pt[2] = a;
+    newt++;
+
+    newt->pt[0] = b;
+    newt->pt[1] = oldt->pt[1];
+    newt->pt[2] = c;
+    newt++;
+
+    newt->pt[0] = a;
+    newt->pt[1] = b;
+    newt->pt[2] = c;
+    newt++;
+
+    newt->pt[0] = a;
+    newt->pt[1] = c;
+    newt->pt[2] = oldt->pt[2];
+  }
+}
+
+int drawSphere(vec3 *origin, float radius, int level) {
+  int lv, i;
+  object oldObj, newObj;
+
+  if (level < 1) {
+    fprintf(stderr, "%s:level max greater than 0.\n", __FUNCTION__);
+    return -1;
+  }
+
+  oldObj.npoly = sizeof(octahedron) / sizeof(octahedron[0]);
+  oldObj.poly = (triangle *)malloc(oldObj.npoly * sizeof(triangle));
+  if (!oldObj.poly) {
+    fprintf(stderr, "%s:insufficient memory.\n", __FUNCTION__);
+    return -1;
+  }
+  memcpy(oldObj.poly, octahedron, oldObj.npoly * sizeof(triangle));
+
+  for (lv = 0; lv < level; lv++) {
+    newObj.npoly = oldObj.npoly * 4;
+    newObj.poly = (triangle *)malloc(newObj.npoly * sizeof(triangle));
+    if (!newObj.poly) {
+      fprintf(stderr, "%s:insufficient memory(levelLoop:%d).\n",
+        __FUNCTION__, lv);
+      free(oldObj.poly);
+      return -1;
+    }
+
+    subdivide(&oldObj, &newObj);
+
+    free(oldObj.poly);
+    oldObj = newObj;
+  }
+
+  glPushMatrix();
+  glTranslatef(origin->x, origin->y, origin->z);
+  glScalef(radius, radius, radius);
+  for (i = 0; i < newObj.npoly; ++i) {
+    drawTriangle(&newObj.poly[i]);
+  }
+  glPopMatrix();
+
+  free(newObj.poly);
+
+  return 0;
+}
+
+void drawTriangle(triangle *poly) {
+  int i;
+  glBegin(GL_TRIANGLES);
+  for (i = 0; i < 3; ++i) {
+    vec3 *pt = &poly->pt[i];
+    glNormal3f(pt->x, pt->y, pt->z);
+    glVertex3f(pt->x, pt->y, pt->z);
+  }
+  glEnd();
+}
+
+int drawCylinder(vec3 *topOrigin, vec3 *bottomOrigin, float radius, int slices) {
+  float theta = (2.0 * M_PI) / (float)slices;
+  float a = 0.0f;
+  int lv;
+  float x, y, z;
+  vec3 zAxis = {0, 0, 1};
+  vec3 p, t;
+  float height = 0;
+  float angle = 0;
+
+  if (slices <= 0) {
+    fprintf(stderr, "%s:Invalid parameter(slices:%d).\n", __FUNCTION__, slices);
+    return -1;
+  }
+
+  vec3Sub(topOrigin, bottomOrigin, &p);
+  vec3CrossProduct(&zAxis, &p, &t);
+  height = vec3Length(&p);
+  if (height > 0) {
+    angle = 180 / M_PI * acos(vec3DotProduct(&zAxis, &p) / height);
+  }
+
+  glPushMatrix();
+
+  glTranslatef(bottomOrigin->x, bottomOrigin->y,
+    bottomOrigin->z);
+  glRotatef(angle, t.x, t.y, t.z);
+
+  // strips
+  glBegin(GL_TRIANGLE_STRIP);
+  for (a = 0, lv = 0; lv <= slices; ++lv) {
+    float cosa = cos(a);
+    float sina = sin(a);
+    x = cosa * radius;
+    y = sina * radius;
+    z = 0;
+    glNormal3f(cosa, sina, 0);
+    glVertex3f(x, y, z);
+    z = height;
+    glNormal3f(cosa, sina, 0);
+    glVertex3f(x, y, z);
+    a += theta;
+  }
+  glEnd();
+
+  // bottom cap
+  z = 0;
+  glBegin(GL_TRIANGLE_FAN);
+  glNormal3f(0, 0, -1);
+  glVertex3f(0, 0, z);
+  for (a = 0, lv = 0; lv <= slices; ++lv) {
+    x = cos(a) * radius;
+    y = sin(a) * radius;
+    glNormal3f(0, 0, -1);
+    glVertex3f(x, y, z);
+    a += theta;
+  }
+  glEnd();
+
+  // top cap
+  z = height;
+  glBegin(GL_TRIANGLE_FAN);
+  glNormal3f(0, 0, 1);
+  glVertex3f(0, 0, z);
+  for (a = 0, lv = 0; lv <= slices; ++lv) {
+    x = cos(a) * radius;
+    y = sin(a) * radius;
+    glNormal3f(0, 0, 1);
+    glVertex3f(x, y, z);
+    a += theta;
+  }
+  glEnd();
+
+  glPopMatrix();
+
+  return 0;
+}
+
+int drawGrid(float size, float step) {
+  glDisable(GL_LIGHTING);
+
+  // x z plane
+  glBegin(GL_LINES);
+  for (GLfloat i = -size; i <= size; i += step) {
+    if (0 == i) {
+      glColor3f(0.0, 0.0, 1.0);
+      glVertex3f(i, 0, size); glVertex3f(i, 0, -size);
+      glColor3f(1.0, 0.0, 0.0);
+      glVertex3f(size, 0, i); glVertex3f(-size, 0, i);
+    } else {
+      glColor3f(0.39, 0.39, 0.39);
+      glVertex3f(i, 0, size); glVertex3f(i, 0, -size);
+      glVertex3f(size, 0, i); glVertex3f(-size, 0, i);
+    }
+  }
+  glEnd();
+
+  glEnable(GL_LIGHTING);
+  return 0;
+}

src/draw.h

@@ -0,0 +1,27 @@
+#ifndef DRAW_SPHERE_H
+#define DRAW_SPHERE_H
+#include "vector3d.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+  vec3 pt[3];
+} triangle;
+
+typedef struct {
+  int npoly;
+  triangle *poly;
+} object;
+
+int drawSphere(vec3 *origin, float radius, int level);
+void drawTriangle(triangle *poly);
+int drawCylinder(vec3 *topOrigin, vec3 *bottomOrigin, float radius, int slices);
+int drawGrid(float size, float step);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif

src/drawcommon.h

@@ -1,18 +1,13 @@
 #ifndef DRAW_COMMON_H
 #define DRAW_COMMON_H
+#include "vector3d.h"
 
 #ifdef __cplusplus
 extern "C" {
 #endif
 
 typedef struct {
-  float x;
+  vec3 pt[3];
-  float y;
-  float z;
-} point;
-
-typedef struct {
-  point pt[3];
 } triangle;
 
 typedef struct {
@@ -20,8 +15,6 @@ typedef struct {
   triangle *poly;
 } object;
 
-void normalize(point *p);
-void midpoint(point *a, point *b, point *mid);
 void drawTriangle(triangle *poly);
 int drawCylinder(int slices, float radius, float height);
 

src/mainwindow.cpp

@@ -2,29 +2,21 @@
 #include <QHBoxLayout>
 #include <QDesktopWidget>
 #include "mainwindow.h"
+#include "render.h"
 
-MainWindow::MainWindow(void) 
+MainWindow::MainWindow(void) {
-{
+	render = new Render;
-	glWidget = new GLWidget;
-
   resize(QDesktopWidget().availableGeometry(this).size() * 0.7);
-
 	QHBoxLayout *mainLayout = new QHBoxLayout;
-    mainLayout->addWidget(glWidget);
+  mainLayout->addWidget(render);
   setLayout(mainLayout);
-
+  setWindowTitle(tr("Dust3D Experiment"));
-    setWindowTitle(tr("DUST3D"));
 }
 
-void MainWindow::keyPressEvent(QKeyEvent *e) 
+void MainWindow::keyPressEvent(QKeyEvent *e) {
-{
+  if (e->key() == Qt::Key_Escape) {
-    if (e->key() == Qt::Key_Escape) 
-    {
   	close();
-    } 
+  } else {
-    else 
-    {
     QWidget::keyPressEvent(e);
   }
 }
-

src/mainwindow.h

@@ -2,10 +2,10 @@
 #define MAINWINDOW_H
 
 #include <QWidget>
-#include "glwidget.h"
 
-class MainWindow : public QWidget 
+class Render;
-{
+
+class MainWindow : public QWidget {
 	Q_OBJECT
 
 public:
@@ -15,7 +15,7 @@ protected:
   void keyPressEvent(QKeyEvent *event);
 
 private:
-	GLWidget *glWidget;
+	Render *render;
 };
 
 #endif

src/matrix.c

@@ -0,0 +1,184 @@
+#include "matrix.h"
+#include <string.h>
+#include <math.h>
+
+#define DEG2RAD (M_PI / 180.0)
+
+matrix *matrixLoadIdentity(matrix *mat) {
+  memset(mat->data, 0, sizeof(mat->data));
+  mat->data[0] = 1;
+  mat->data[5] = 1;
+  mat->data[10] = 1;
+  mat->data[15] = 1;
+  return mat;
+}
+
+matrix *matrixTranslate(matrix *mat, float x, float y, float z) {
+  matrixLoadIdentity(mat);
+  mat->data[12] = x;
+  mat->data[13] = y;
+  mat->data[14] = z;
+  return mat;
+}
+
+matrix *matrixRotateX(matrix *mat, float degree) {
+  float c;
+  float s;
+  
+  matrixLoadIdentity(mat);
+  
+  if (degree <= 0) {
+    return mat;
+  }
+  
+  c = cos(degree * DEG2RAD);
+  s = sin(degree * DEG2RAD);
+
+  mat->data[5] = c;
+  mat->data[6] = s;
+  mat->data[9] = -s;
+  mat->data[10] = c;
+  
+  return mat;
+}
+
+matrix *matrixRotateY(matrix *mat, float degree) {
+  float c;
+  float s;
+  
+  matrixLoadIdentity(mat);
+  
+  if (degree <= 0) {
+    return mat;
+  }
+  
+  c = cos(degree * DEG2RAD);
+  s = sin(degree * DEG2RAD);
+
+  mat->data[0] = c;
+  mat->data[2] = -s;
+  mat->data[8] = s;
+  mat->data[10] = c;
+  
+  return mat;
+}
+
+matrix *matrixRotateZ(matrix *mat, float degree) {
+  float c;
+  float s;
+  
+  matrixLoadIdentity(mat);
+  
+  if (degree <= 0) {
+    return mat;
+  }
+  
+  c = cos(degree * DEG2RAD);
+  s = sin(degree * DEG2RAD);
+
+  mat->data[0] = c;
+  mat->data[1] = s;
+  mat->data[4] = -s;
+  mat->data[5] = c;
+  
+  return mat;
+}
+
+matrix *matrixScale(matrix *mat, float x, float y, float z) {
+  matrixLoadIdentity(mat);
+  mat->data[0] = x;
+  mat->data[5] = y;
+  mat->data[10] = z;
+  return mat;
+}
+
+float *matrixTransformVector(matrix *mat, float *vec) {
+  float x = (vec[0] * mat->data[0]) + 
+      (vec[1] * mat->data[4]) + (vec[2] * mat->data[8]) + mat->data[12];
+  float y = (vec[0] * mat->data[1]) + 
+      (vec[1] * mat->data[5]) + (vec[2] * mat->data[9]) + mat->data[13];
+  float z = (vec[0] * mat->data[2]) + 
+      (vec[1] * mat->data[6]) + (vec[2] * mat->data[10]) + mat->data[14];
+  vec[0] = x;
+  vec[1] = y;
+  vec[2] = z;
+  return vec;
+}
+
+matrix *matrixAppend(matrix *mat, matrix *matB) {
+  matrix structMatA;
+  matrix *matA = &structMatA;
+  
+  memcpy(matA, mat, sizeof(matrix));
+  
+  mat->data[0] = matA->data[0] * matB->data[0] + 
+      matA->data[4] * matB->data[1] + 
+      matA->data[8] * matB->data[2] + 
+      matA->data[12] * matB->data[3];
+  mat->data[4] = matA->data[0] * matB->data[4] + 
+      matA->data[4] * matB->data[5] + 
+      matA->data[8] * matB->data[6] + 
+      matA->data[12] * matB->data[7];
+  mat->data[8] = matA->data[0] * matB->data[8] + 
+      matA->data[4] * matB->data[9] + 
+      matA->data[8] * matB->data[10] + 
+      matA->data[12] * matB->data[11];
+  mat->data[12] = matA->data[0] * matB->data[12] + 
+      matA->data[4] * matB->data[13] + 
+      matA->data[8] * matB->data[14] + 
+      matA->data[12] * matB->data[15];
+
+  mat->data[1] = matA->data[1] * matB->data[0] + 
+      matA->data[5] * matB->data[1] + 
+      matA->data[9] * matB->data[2] + 
+      matA->data[13] * matB->data[3];
+  mat->data[5] = matA->data[1] * matB->data[4] + 
+      matA->data[5] * matB->data[5] + 
+      matA->data[9] * matB->data[6] + 
+      matA->data[13] * matB->data[7];
+  mat->data[9] = matA->data[1] * matB->data[8] + 
+      matA->data[5] * matB->data[9] + 
+      matA->data[9] * matB->data[10] + 
+      matA->data[13] * matB->data[11];
+  mat->data[13] = matA->data[1] * matB->data[12] + 
+      matA->data[5] * matB->data[13] + 
+      matA->data[9] * matB->data[14] + 
+      matA->data[13] * matB->data[15];
+
+  mat->data[2] = matA->data[2] * matB->data[0] + 
+      matA->data[6] * matB->data[1] + 
+      matA->data[10] * matB->data[2] + 
+      matA->data[14] * matB->data[3];
+  mat->data[6] = matA->data[2] * matB->data[4] + 
+      matA->data[6] * matB->data[5] + 
+      matA->data[10] * matB->data[6] + 
+      matA->data[14] * matB->data[7];
+  mat->data[10] = matA->data[2] * matB->data[8] + 
+      matA->data[6] * matB->data[9] + 
+      matA->data[10] * matB->data[10] + 
+      matA->data[14] * matB->data[11];
+  mat->data[14] = matA->data[2] * matB->data[12] + 
+      matA->data[6] * matB->data[13] + 
+      matA->data[10] * matB->data[14] + 
+      matA->data[14] * matB->data[15];
+
+  mat->data[3] = matA->data[3] * matB->data[0] + 
+      matA->data[7] * matB->data[1] + 
+      matA->data[11] * matB->data[2] + 
+      matA->data[15] * matB->data[3];
+  mat->data[7] = matA->data[3] * matB->data[4] + 
+      matA->data[7] * matB->data[5] + 
+      matA->data[11] * matB->data[6] + 
+      matA->data[15] * matB->data[7];
+  mat->data[11] = matA->data[3] * matB->data[8] + 
+      matA->data[7] * matB->data[9] + 
+      matA->data[11] * matB->data[10] + 
+      matA->data[15] * matB->data[11];
+  mat->data[15] = matA->data[3] * matB->data[12] + 
+      matA->data[7] * matB->data[13] + 
+      matA->data[11] * matB->data[14] + 
+      matA->data[15] * matB->data[15];
+      
+  return mat;
+}
+

src/matrix.h

@@ -0,0 +1,19 @@
+#ifndef __MATRIX_H__
+#define __MATRIX_H__
+
+// Modified from http://wiki.unity3d.com/index.php?title=Matrix
+
+typedef struct matrix {
+  float data[16];
+} matrix;
+
+matrix *matrixLoadIdentity(matrix *mat);
+matrix *matrixTranslate(matrix *mat, float x, float y, float z);
+matrix *matrixRotateX(matrix *mat, float degree);
+matrix *matrixRotateY(matrix *mat, float degree);
+matrix *matrixRotateZ(matrix *mat, float degree);
+matrix *matrixScale(matrix *mat, float x, float y, float z);
+float *matrixTransformVector(matrix *mat, float *vec);
+matrix *matrixAppend(matrix *mat, matrix *matB);
+
+#endif

src/render.cpp

@@ -0,0 +1,160 @@
+#include <QtGui>
+#include <QtOpenGL>
+#include <assert.h>
+#include <math.h>
+#include "render.h"
+#include "draw.h"
+#include "bmesh.h"
+#include "matrix.h"
+
+static int drawBmeshNode(bmesh *bm, bmeshNode *node) {
+  float color1[3] = {1, 0, 0};
+  glColor3fv(color1);
+  drawSphere(&node->position, node->radius, 3);
+  return 0;
+}
+
+static int drawBmeshEdge(bmesh *bm, bmeshEdge *edge) {
+  float color2[3] = {0, 0, 1};
+  glColor3fv(color2);
+  bmeshNode *firstNode = bmeshGetNode(bm, edge->firstNode);
+  bmeshNode *secondNode = bmeshGetNode(bm, edge->secondNode);
+  drawCylinder(&firstNode->position, &secondNode->position, 0.04, 40);
+  return 0;
+}
+
+Render::Render(QWidget *parent)
+    : QGLWidget(QGLFormat(QGL::SampleBuffers), parent) {
+  QTimer *timer = new QTimer(this);
+  connect(timer, SIGNAL(timeout()), this, SLOT(update()));
+  timer->start(100);
+
+  mouseX = 0;
+  mouseY = 0;
+  cameraAngleX = 50;
+  cameraAngleY = 70;
+  cameraDistance = 3;
+}
+
+Render::~Render(void) {
+}
+
+void Render::initializeGL() {
+  glShadeModel(GL_SMOOTH);
+  glEnable(GL_CULL_FACE);
+  glEnable(GL_BLEND);
+
+  qglClearColor(QWidget::palette().color(QWidget::backgroundRole()));
+  glClearDepth(1.0f);
+
+  GLfloat ambientLight[] = {0.0f, 0.0f, 0.0f, 1.0f};
+  GLfloat diffuseLight[] = {0.9f, 0.9f, 0.9f, 1.0f};
+  GLfloat specularLight[] = {1, 1, 1, 1};
+  glLightfv(GL_LIGHT0, GL_AMBIENT, ambientLight);
+  glLightfv(GL_LIGHT0, GL_DIFFUSE, diffuseLight);
+  glLightfv(GL_LIGHT0, GL_SPECULAR, specularLight);
+
+  float lightDirection[4] = {0, 0, 1, 0};
+  glLightfv(GL_LIGHT0, GL_POSITION, lightDirection);
+
+  glEnable(GL_LIGHT0);
+
+  float shininess = 64.0f;
+  float specularColor[] = {1.0, 1.0f, 1.0f, 1.0f};
+	glMaterialf(GL_FRONT_AND_BACK, GL_SHININESS, shininess); // range 0 ~ 128
+	glMaterialfv(GL_FRONT_AND_BACK, GL_SPECULAR, specularColor);
+
+  glClearStencil(0);
+  glClearDepth(1.0f);
+  glDepthFunc(GL_LEQUAL);
+  glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
+  glEnable(GL_DEPTH_TEST);
+  glEnable(GL_LIGHTING);
+  glEnable(GL_CULL_FACE);
+
+  glColorMaterial(GL_FRONT_AND_BACK, GL_AMBIENT_AND_DIFFUSE);
+  glEnable(GL_COLOR_MATERIAL);
+}
+
+void Render::paintGL() {
+  static bmesh *bm = 0;
+
+  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+  glPushMatrix();
+
+  glTranslatef(0, 0, -cameraDistance);
+  glRotatef(cameraAngleX, 1, 0, 0);
+  glRotatef(cameraAngleY, 0, 1, 0);
+
+  drawGrid(10, 1);
+
+  glEnable(GL_LIGHTING);
+
+  if (0 == bm) {
+    bmeshNode node;
+    bmeshEdge edge;
+    bm = bmeshCreate();
+
+    memset(&node, 0, sizeof(node));
+    node.position.x = -1.0;
+    node.position.y = 0.3;
+    node.position.z = 1.0;
+    node.radius = 0.45;
+    bmeshAddNode(bm, &node);
+
+    memset(&node, 0, sizeof(node));
+    node.position.x = -0.5;
+    node.position.y = 0.2;
+    node.position.z = 0.5;
+    node.radius = 0.1;
+    bmeshAddNode(bm, &node);
+
+    memset(&edge, 0, sizeof(edge));
+    edge.firstNode = 1;
+    edge.secondNode = 0;
+    bmeshAddEdge(bm, &edge);
+  }
+
+  {
+    int index;
+    for (index = 0; index < bmeshGetNodeNum(bm); ++index) {
+      bmeshNode *node = bmeshGetNode(bm, index);
+      drawBmeshNode(bm, node);
+    }
+    for (index = 0; index < bmeshGetEdgeNum(bm); ++index) {
+      bmeshEdge *edge = bmeshGetEdge(bm, index);
+      drawBmeshEdge(bm, edge);
+    }
+  }
+
+  glPopMatrix();
+}
+
+void Render::resizeGL(int w, int h) {
+  glViewport(0, 0, (GLsizei)w, (GLsizei)h);
+
+  glMatrixMode(GL_PROJECTION);
+  glLoadIdentity();
+  glFrustum(-2, 2, -1.5, 1.5, 1, 1000);
+
+  glMatrixMode(GL_MODELVIEW);
+  glLoadIdentity();
+}
+
+void Render::mousePressEvent(QMouseEvent *event) {
+  mouseX = event->x();
+  mouseY = event->y();
+}
+
+void Render::mouseMoveEvent(QMouseEvent *event) {
+  cameraAngleY += (event->x() - mouseX);
+  cameraAngleX += (event->y() - mouseY);
+  update();
+  mouseX = event->x();
+  mouseY = event->y();
+}
+
+void Render::wheelEvent(QWheelEvent * event) {
+  cameraDistance -= event->delta() * 0.01f;
+}

src/render.h

@@ -0,0 +1,29 @@
+#ifndef RENDER_H
+#define RENDER_H
+
+#include <QGLWidget>
+
+class Render : public QGLWidget {
+  Q_OBJECT
+
+public:
+  Render(QWidget *parent = 0);
+  ~Render(void);
+
+protected:
+  void initializeGL(void);
+  void paintGL(void);
+  void resizeGL(int width, int height);
+  void mousePressEvent(QMouseEvent *event);
+  void mouseMoveEvent(QMouseEvent *event);
+  void wheelEvent(QWheelEvent * event);
+
+private:
+  int mouseX;
+  int mouseY;
+  float cameraAngleX;
+  float cameraAngleY;
+  float cameraDistance;
+};
+
+#endif

src/vector3d.c

@@ -0,0 +1,40 @@
+#include "vector3d.h"
+
+float vec3Length(vec3 *p) {
+  double mag;
+  mag = p->x * p->x + p->y * p->y + p->z * p->z;
+  return sqrt(mag);
+}
+
+void vec3Normalize(vec3 *p) {
+  double mag;
+  mag = p->x * p->x + p->y * p->y + p->z * p->z;
+  if (mag != 0.0) {
+    mag = 1.0 / sqrt(mag);
+    p->x *= mag;
+    p->y *= mag;
+    p->z *= mag;
+  }
+}
+
+void vec3Midpoint(vec3 *a, vec3 *b, vec3 *mid) {
+  mid->x = (a->x + b->x) * 0.5;
+  mid->y = (a->y + b->y) * 0.5;
+  mid->z = (a->z + b->z) * 0.5;
+}
+
+void vec3Sub(vec3 *a, vec3 *b, vec3 *result) {
+  result->x = a->x - b->x;
+  result->y = a->y - b->y;
+  result->z = a->z - b->z;
+}
+
+void vec3CrossProduct(vec3 *a, vec3 *b, vec3 *result) {
+  result->x = a->y * b->z - a->z * b->y;
+  result->y = a->z * b->x - a->x * b->z;
+  result->z = a->x * b->y - a->y * b->x;
+}
+
+float vec3DotProduct(vec3 *a, vec3 *b) {
+  return a->x * b->x + a->y * b->y + a->z * b->z;
+}

src/vector3d.h

@@ -0,0 +1,25 @@
+#ifndef VECTOR_3D_H
+#define VECTOR_3D_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef struct {
+  float x;
+  float y;
+  float z;
+} vec3;
+
+void vec3Normalize(vec3 *p);
+void vec3Midpoint(vec3 *a, vec3 *b, vec3 *mid);
+void vec3CrossProduct(vec3 *a, vec3 *b, vec3 *result);
+void vec3Sub(vec3 *a, vec3 *b, vec3 *result);
+float vec3DotProduct(vec3 *a, vec3 *b);
+float vec3Length(vec3 *p);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif