Add the old Bullet 2.x obsolete demos, and CMake buildsystem files, and gradually move them to newer Bullet 3.x structure

Use statically linked freeglut, instead of dynamic glut for the obsolete Bullet 2.x demos
Add the 'reset' method to b3GpuDynamicsWorld, and use it in the BasicGpuDemo (pretty slow in debug mode, use release mode)
Don't crash in btCollisionWorld, if there is no collision dispatcher

ObsoleteDemos/NativeClient/transforms.cc

@@ -0,0 +1,116 @@
+// Copyright (c) 2011 The Native Client Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "transforms.h"
+
+#include <math.h>
+#include <string.h>
+#include <GLES2/gl2.h>
+
+namespace transform_4x4 {
+
+static const GLfloat kPI = 3.1415926535897932384626433832795f;
+
+void Translate(GLfloat* m, GLfloat tx, GLfloat ty, GLfloat tz) {
+  m[12] += (m[0] * tx + m[4] * ty + m[8] * tz);
+  m[13] += (m[1] * tx + m[5] * ty + m[9] * tz);
+  m[14] += (m[2] * tx + m[6] * ty + m[10] * tz);
+  m[15] += (m[3] * tx + m[7] * ty + m[11] * tz);
+}
+
+void Frustum(GLfloat* m,
+             GLfloat left,
+             GLfloat right,
+             GLfloat bottom,
+             GLfloat top,
+             GLfloat near_z,
+             GLfloat far_z) {
+  GLfloat delta_x = right - left;
+  GLfloat delta_y = top - bottom;
+  GLfloat delta_z = far_z - near_z;
+  GLfloat frustum[16];
+
+  if ((near_z <= 0.0f) || (far_z <= 0.0f) ||
+     (delta_x <= 0.0f) || (delta_y <= 0.0f) || (delta_z <= 0.0f))
+     return;
+
+  frustum[0] = 2.0f * near_z / delta_x;
+  frustum[1] = frustum[2] = frustum[3] = 0.0f;
+
+  frustum[5] = 2.0f * near_z / delta_y;
+  frustum[4] = frustum[6] = frustum[7] = 0.0f;
+
+  frustum[8] = (right + left) / delta_x;
+  frustum[9] = (top + bottom) / delta_y;
+  frustum[10] = -(near_z + far_z) / delta_z;
+  frustum[11] = -1.0f;
+
+  frustum[14] = -2.0f * near_z * far_z / delta_z;
+  frustum[12] = frustum[13] = frustum[15] = 0.0f;
+
+  transform_4x4::Multiply(m, frustum, m);
+}
+
+
+void Perspective(GLfloat* m,
+                 GLfloat fovy,
+                 GLfloat aspect,
+                 GLfloat near_z,
+                 GLfloat far_z) {
+  GLfloat frustum_w, frustum_h;
+
+  frustum_h = tanf((fovy * 0.5f) / 180.0f * kPI) * near_z;
+  frustum_w = frustum_h * aspect;
+  transform_4x4::Frustum(m, -frustum_w, frustum_w, -frustum_h, frustum_h,
+                         near_z, far_z);
+}
+
+void Multiply(GLfloat *m, GLfloat *a, GLfloat* b) {
+  GLfloat tmp[16];
+  // tmp = a . b
+  GLfloat a0, a1, a2, a3;
+  a0 = a[0];
+  a1 = a[1];
+  a2 = a[2];
+  a3 = a[3];
+  tmp[0] = a0 * b[0] + a1 * b[4] + a2 * b[8] + a3 * b[12];
+  tmp[1] = a0 * b[1] + a1 * b[5] + a2 * b[9] + a3 * b[13];
+  tmp[2] = a0 * b[2] + a1 * b[6] + a2 * b[10] + a3 * b[14];
+  tmp[3] = a0 * b[3] + a1 * b[7] + a2 * b[11] + a3 * b[15];
+
+  a0 = a[4];
+  a1 = a[5];
+  a2 = a[6];
+  a3 = a[7];
+  tmp[4] = a0 * b[0] + a1 * b[4] + a2 * b[8] + a3 * b[12];
+  tmp[5] = a0 * b[1] + a1 * b[5] + a2 * b[9] + a3 * b[13];
+  tmp[6] = a0 * b[2] + a1 * b[6] + a2 * b[10] + a3 * b[14];
+  tmp[7] = a0 * b[3] + a1 * b[7] + a2 * b[11] + a3 * b[15];
+
+  a0 = a[8];
+  a1 = a[9];
+  a2 = a[10];
+  a3 = a[11];
+  tmp[8] = a0 * b[0] + a1 * b[4] + a2 * b[8] + a3 * b[12];
+  tmp[9] = a0 * b[1] + a1 * b[5] + a2 * b[9] + a3 * b[13];
+  tmp[10] = a0 * b[2] + a1 * b[6] + a2 * b[10] + a3 * b[14];
+  tmp[11] = a0 * b[3] + a1 * b[7] + a2 * b[11] + a3 * b[15];
+
+  a0 = a[12];
+  a1 = a[13];
+  a2 = a[14];
+  a3 = a[15];
+  tmp[12] = a0 * b[0] + a1 * b[4] + a2 * b[8] + a3 * b[12];
+  tmp[13] = a0 * b[1] + a1 * b[5] + a2 * b[9] + a3 * b[13];
+  tmp[14] = a0 * b[2] + a1 * b[6] + a2 * b[10] + a3 * b[14];
+  tmp[15] = a0 * b[3] + a1 * b[7] + a2 * b[11] + a3 * b[15];
+  memcpy(m, tmp, sizeof(GLfloat) * 4 * 4);
+}
+
+void LoadIdentity(GLfloat* m) {
+  memset(m, 0, sizeof(GLfloat) * 4 * 4);
+  m[0] = m[5] = m[10] = m[15] = 1.0f;
+}
+
+}  // namespace transform_4x4