[NaCl SDK] Simplify graphics3d example.

native_client_sdk/src/examples/api/graphics_3d/graphics_3d.cc

-// Copyright (c) 2012 The Chromium Authors. All rights reserved.
+// Copyright (c) 2013 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-//-----------------------------------------------------------------------------
-// The spinning Cube
-//-----------------------------------------------------------------------------
-
-#define _USE_MATH_DEFINES 1
-#include <limits.h>
+#include <GLES2/gl2.h>
 #include <math.h>
-#include <stdarg.h>
 #include <stddef.h>
+#include <stdint.h>
 #include <stdio.h>
-#include <stdlib.h>
 #include <string.h>
 
-#include "ppapi/c/pp_completion_callback.h"
-#include "ppapi/c/pp_errors.h"
-#include "ppapi/c/pp_graphics_3d.h"
-#include "ppapi/c/pp_module.h"
-#include "ppapi/c/pp_stdint.h"
-#include "ppapi/c/pp_var.h"
-#include "ppapi/c/ppb.h"
-#include "ppapi/c/ppb_core.h"
-#include "ppapi/c/ppb_graphics_3d.h"
-#include "ppapi/c/ppb_instance.h"
-#include "ppapi/c/ppb_messaging.h"
-#include "ppapi/c/ppb_opengles2.h"
-#include "ppapi/c/ppb_url_loader.h"
-#include "ppapi/c/ppb_url_request_info.h"
-#include "ppapi/c/ppb_var.h"
-#include "ppapi/c/ppp.h"
-#include "ppapi/c/ppp_instance.h"
-#include "ppapi/c/ppp_messaging.h"
-
-#include "ppapi/c/ppp_graphics_3d.h"
+#include "matrix.h"
+#include "ppapi/cpp/graphics_3d.h"
+#include "ppapi/cpp/instance.h"
+#include "ppapi/cpp/module.h"
+#include "ppapi/cpp/var.h"
+#include "ppapi/cpp/var_array.h"
 #include "ppapi/lib/gl/gles2/gl2ext_ppapi.h"
-
-#include <GLES2/gl2.h>
-#include "matrix.h"
-
-static PPB_Messaging* ppb_messaging_interface = NULL;
-static PPB_Var* ppb_var_interface = NULL;
-static PPB_Core* ppb_core_interface = NULL;
-static PPB_Graphics3D* ppb_g3d_interface = NULL;
-static PPB_Instance* ppb_instance_interface = NULL;
-static PPB_URLRequestInfo* ppb_urlrequestinfo_interface = NULL;
-static PPB_URLLoader* ppb_urlloader_interface = NULL;
-
-static PP_Instance g_instance;
-static PP_Resource g_context;
-
-GLuint g_positionLoc;
-GLuint g_texCoordLoc;
-GLuint g_colorLoc;
-GLuint g_MVPLoc;
-GLuint g_vboID;
-GLuint g_ibID;
-GLubyte g_Indices[36];
-
-GLuint g_programObj;
-GLuint g_vertexShader;
-GLuint g_fragmentShader;
-
-GLuint g_textureLoc = 0;
-GLuint g_textureID = 0;
-
-float g_fSpinX = 0.0f;
-float g_fSpinY = 0.0f;
-
-//-----------------------------------------------------------------------------
-// Rendering Assets
-//-----------------------------------------------------------------------------
-struct Vertex {
-  float tu, tv;
-  float color[3];
-  float loc[3];
-};
-
-Vertex* g_quadVertices = NULL;
-const char* g_TextureData = NULL;
-const char* g_VShaderData = NULL;
-const char* g_FShaderData = NULL;
-int g_LoadCnt = 0;
-
-//-----------------------------------------------------------------------------
-// PROTOTYPES
-//-----------------------------------------------------------------------------
-void PostMessage(const char* fmt, ...);
-char* LoadFile(const char* fileName);
-
-void BuildQuad(Vertex* verts, int axis[3], float depth, float color[3]);
-Vertex* BuildCube(void);
-
-void InitGL(void);
-void InitProgram(void);
-void Render(void);
-
-static struct PP_Var CStrToVar(const char* str) {
-  if (ppb_var_interface != NULL) {
-    return ppb_var_interface->VarFromUtf8(str, strlen(str));
-  }
-  return PP_MakeUndefined();
+#include "ppapi/utility/completion_callback_factory.h"
+
+#ifdef WIN32
+#undef PostMessage
+// Allow 'this' in initializer list
+#pragma warning(disable : 4355)
+#endif
+
+extern const uint8_t kRLETextureData[];
+extern const size_t kRLETextureDataLength;
+
+namespace {
+
+const float kFovY = 45.0f;
+const float kZNear = 1.0f;
+const float kZFar = 10.0f;
+const float kCameraZ = -4.0f;
+const float kXAngleDelta = 2.0f;
+const float kYAngleDelta = 0.5f;
+
+const size_t kTextureDataLength = 128 * 128 * 3;  // 128x128, 3 Bytes/pixel.
+
+// The decompressed data is written here.
+uint8_t g_texture_data[kTextureDataLength];
+
+void DecompressTexture() {
+  // The image is first encoded with a very simple RLE scheme:
+  //   <value0> <count0> <value1> <count1> ...
+  // Because a <count> of 0 is useless, we use it to represent 256.
+  //
+  // It is then Base64 encoded to make it use only printable characters (it
+  // stores more easily in a source file that way).
+  //
+  // To decompress, we have to reverse the process.
+  static const uint8_t kBase64Decode[256] = {
+    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
+    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0,
+    0,  0,  0,  0,  0,  0,  0,  0,  0,  0,  0, 62,  0,  0,  0, 63,
+   52, 53, 54, 55, 56, 57, 58, 59, 60, 61,  0,  0,  0,  0,  0,  0,
+    0,  0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14,
+   15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25,  0,  0,  0,  0,  0,
+    0, 26, 27, 28, 29, 30, 31, 32, 33, 34, 35, 36, 37, 38, 39, 40,
+   41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51,
+  };
+  const uint8_t* input = &kRLETextureData[0];
+  const uint8_t * const input_end = &kRLETextureData[kRLETextureDataLength];
+  uint8_t* output = &g_texture_data[0];
+  const uint8_t * const output_end = &g_texture_data[kTextureDataLength];
+
+  uint8_t decoded[4];
+  int decoded_count = 0;
+
+  while (input < input_end || decoded_count > 0) {
+    if (decoded_count < 2) {
+      assert(input + 4 <= input_end);
+      // Grab four base-64 encoded (6-bit) bytes.
+      uint32_t data = 0;
+      data |= (kBase64Decode[*input++] << 18);
+      data |= (kBase64Decode[*input++] << 12);
+      data |= (kBase64Decode[*input++] <<  6);
+      data |= (kBase64Decode[*input++]      );
+      // And decode it to 3 (8-bit) bytes.
+      decoded[decoded_count++] = (data >> 16) & 0xff;
+      decoded[decoded_count++] = (data >>  8) & 0xff;
+      decoded[decoded_count++] = (data      ) & 0xff;
+
+      // = is the base64 end marker. Remove decoded bytes if we see any.
+      if (input[-1] == '=') decoded_count--;
+      if (input[-2] == '=') decoded_count--;
+    }
+
+    int value = decoded[0];
+    int count = decoded[1];
+    decoded_count -= 2;
+    // Move the other decoded bytes (if any) down.
+    decoded[0] = decoded[2];
+    decoded[1] = decoded[3];
+
+    // Expand the RLE data.
+    if (count == 0)
+      count = 256;
+    assert(output <= output_end);
+    memset(output, value, count);
+    output += count;
+  }
+  assert(output == output_end);
 }
 
-void PostMessage(const char* fmt, ...) {
-  va_list args;
-  va_start(args, fmt);
-
-  char msg[4096];
-  vsnprintf(msg, sizeof(msg), fmt, args);
-
-  if (ppb_messaging_interface)
-    ppb_messaging_interface->PostMessage(g_instance, CStrToVar(msg));
-
-  va_end(args);
-}
-
-void MainLoop(void* foo, int bar) {
-  if (g_LoadCnt == 3) {
-    InitProgram();
-    g_LoadCnt++;
-  }
-  if (g_LoadCnt > 3) {
-    Render();
-    PP_CompletionCallback cc = PP_MakeCompletionCallback(MainLoop, 0);
-    ppb_g3d_interface->SwapBuffers(g_context, cc);
-  } else {
-    PP_CompletionCallback cc = PP_MakeCompletionCallback(MainLoop, 0);
-    ppb_core_interface->CallOnMainThread(0, cc, 0);
-  }
-}
-
-void InitGL(void) {
-  int32_t attribs[] = {
-    PP_GRAPHICS3DATTRIB_ALPHA_SIZE, 8,
-    PP_GRAPHICS3DATTRIB_DEPTH_SIZE, 24,
-    PP_GRAPHICS3DATTRIB_STENCIL_SIZE, 8,
-    PP_GRAPHICS3DATTRIB_SAMPLES, 0,
-    PP_GRAPHICS3DATTRIB_SAMPLE_BUFFERS, 0,
-    PP_GRAPHICS3DATTRIB_WIDTH, 640,
-    PP_GRAPHICS3DATTRIB_HEIGHT, 480,
-    PP_GRAPHICS3DATTRIB_NONE
-  };
-
-  g_context = ppb_g3d_interface->Create(g_instance, 0, attribs);
-  int32_t success = ppb_instance_interface->BindGraphics(g_instance, g_context);
-  if (success == PP_FALSE) {
-    glSetCurrentContextPPAPI(0);
-    printf("Failed to set context.\n");
-    return;
-  }
-  glSetCurrentContextPPAPI(g_context);
-
-  glViewport(0, 0, 640, 480);
-  glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
-}
-
-GLuint compileShader(GLenum type, const char* data) {
-  const char* shaderStrings[1];
-  shaderStrings[0] = data;
-
+GLuint CompileShader(GLenum type, const char* data) {
   GLuint shader = glCreateShader(type);
-  glShaderSource(shader, 1, shaderStrings, NULL);
+  glShaderSource(shader, 1, &data, NULL);
   glCompileShader(shader);
+
+  GLint compile_status;
+  glGetShaderiv(shader, GL_COMPILE_STATUS, &compile_status);
+  if (compile_status != GL_TRUE) {
+    // Shader failed to compile, let's see what the error is.
+    char buffer[1024];
+    GLsizei length;
+    glGetShaderInfoLog(shader, 1024, &length, &buffer[0]);

[noelallen1, 2013/09/03 20:55:25]

1024 vs sizeof(buffer)?

+    fprintf(stderr, "Shader failed to compile: %s\n", buffer);
+    return 0;
+  }
+
   return shader;
 }
 
-void InitProgram(void) {
-  glSetCurrentContextPPAPI(g_context);
-
-  g_vertexShader = compileShader(GL_VERTEX_SHADER, g_VShaderData);
-  g_fragmentShader = compileShader(GL_FRAGMENT_SHADER, g_FShaderData);
-
-  g_programObj = glCreateProgram();
-  glAttachShader(g_programObj, g_vertexShader);
-  glAttachShader(g_programObj, g_fragmentShader);
-  glLinkProgram(g_programObj);
-
-  glGenBuffers(1, &g_vboID);
-  glBindBuffer(GL_ARRAY_BUFFER, g_vboID);
-  glBufferData(GL_ARRAY_BUFFER,
-               24 * sizeof(Vertex),
-               (void*)&g_quadVertices[0],
-               GL_STATIC_DRAW);
-
-  glGenBuffers(1, &g_ibID);
-  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ibID);
-  glBufferData(GL_ELEMENT_ARRAY_BUFFER,
-               36 * sizeof(char),
-               (void*)&g_Indices[0],
-               GL_STATIC_DRAW);
-
-  //
-  // Create a texture to test out our fragment shader...
-  //
-  glGenTextures(1, &g_textureID);
-  glBindTexture(GL_TEXTURE_2D, g_textureID);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
-  glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
-  glTexImage2D(GL_TEXTURE_2D,
-               0,
-               GL_RGB,
-               128,
-               128,
-               0,
-               GL_RGB,
-               GL_UNSIGNED_BYTE,
-               g_TextureData);
-
-  //
-  // Locate some parameters by name so we can set them later...
-  //
-  g_textureLoc = glGetUniformLocation(g_programObj, "arrowTexture");
-  g_positionLoc = glGetAttribLocation(g_programObj, "a_position");
-  g_texCoordLoc = glGetAttribLocation(g_programObj, "a_texCoord");
-  g_colorLoc = glGetAttribLocation(g_programObj, "a_color");
-  g_MVPLoc = glGetUniformLocation(g_programObj, "a_MVP");
+GLuint LinkProgram(GLuint frag_shader, GLuint vert_shader) {
+  GLuint program = glCreateProgram();
+  glAttachShader(program, frag_shader);
+  glAttachShader(program, vert_shader);
+  glLinkProgram(program);
+
+  GLint link_status;
+  glGetProgramiv(program, GL_LINK_STATUS, &link_status);
+  if (link_status != GL_TRUE) {
+    // Program failed to link, let's see what the error is.
+    char buffer[1024];
+    GLsizei length;
+    glGetProgramInfoLog(program, 1024, &length, &buffer[0]);

[noelallen1, 2013/09/03 20:55:25]

same

+    fprintf(stderr, "Program failed to link: %s\n", buffer);
+    return 0;
+  }
+
+  return program;
 }
 
-void BuildQuad(Vertex* verts, int axis[3], float depth, float color[3]) {
-  static float X[4] = { -1.0f, 1.0f, 1.0f, -1.0f };
-  static float Y[4] = { -1.0f, -1.0f, 1.0f, 1.0f };
-
-  for (int i = 0; i < 4; i++) {
-    verts[i].tu = (1.0 - X[i]) / 2.0f;
-    verts[i].tv = (Y[i] + 1.0f) / -2.0f * depth;
-    verts[i].loc[axis[0]] = X[i] * depth;
-    verts[i].loc[axis[1]] = Y[i] * depth;
-    verts[i].loc[axis[2]] = depth;
-    for (int j = 0; j < 3; j++)
-      verts[i].color[j] = color[j] * (Y[i] + 1.0f) / 2.0f;
-  }
-}
-
-Vertex* BuildCube() {
-  Vertex* verts = new Vertex[24];
-  for (int i = 0; i < 3; i++) {
-    int Faxis[3];
-    int Baxis[3];
-    float Fcolor[3];
-    float Bcolor[3];
-    for (int j = 0; j < 3; j++) {
-      Faxis[j] = (j + i) % 3;
-      Baxis[j] = (j + i) % 3;
-    }
-    memset(Fcolor, 0, sizeof(float) * 3);
-    memset(Bcolor, 0, sizeof(float) * 3);
-    Fcolor[i] = 0.5f;
-    Bcolor[i] = 1.0f;
-    BuildQuad(&verts[0 + i * 4], Faxis, 1.0f, Fcolor);
-    BuildQuad(&verts[12 + i * 4], Baxis, -1.0f, Bcolor);
-  }
-
-  for (int i = 0; i < 6; i++) {
-    g_Indices[i * 6 + 0] = 2 + i * 4;
-    g_Indices[i * 6 + 1] = 1 + i * 4;
-    g_Indices[i * 6 + 2] = 0 + i * 4;
-    g_Indices[i * 6 + 3] = 3 + i * 4;
-    g_Indices[i * 6 + 4] = 2 + i * 4;
-    g_Indices[i * 6 + 5] = 0 + i * 4;
-  }
-  return verts;
-}
-
-void Render(void) {
-  static float xRot = 0.0;
-  static float yRot = 0.0;
-
-  xRot += 2.0f;
-  yRot += 0.5f;
-  if (xRot >= 360.0f)
-    xRot = 0.0;
-  if (yRot >= 360.0f)
-    yRot = 0.0;
-
-  glClearColor(0.5, 0.5, 0.5, 1);
-  glClearDepthf(1.0);
-  glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
-  glEnable(GL_DEPTH_TEST);
-
-  //set what program to use
-  glUseProgram(g_programObj);
-  glActiveTexture(GL_TEXTURE0);
-  glBindTexture(GL_TEXTURE_2D, g_textureID);
-  glUniform1i(g_textureLoc, 0);
-
-  //create our perspective matrix
-  float mpv[16];
-  float trs[16];
-  float rot[16];
-
-  identity_matrix(mpv);
-  glhPerspectivef2(&mpv[0], 45.0f, 640.0f / 480.0f, 1, 10);
-
-  translate_matrix(0, 0, -4.0, trs);
-  rotate_matrix(xRot, yRot, 0.0f, rot);
-  multiply_matrix(trs, rot, trs);
-  multiply_matrix(mpv, trs, mpv);
-  glUniformMatrix4fv(g_MVPLoc, 1, GL_FALSE, (GLfloat*)mpv);
-
-  //define the attributes of the vertex
-  glBindBuffer(GL_ARRAY_BUFFER, g_vboID);
-  glVertexAttribPointer(g_positionLoc,
-                        3,
-                        GL_FLOAT,
-                        GL_FALSE,
-                        sizeof(Vertex),
-                        (void*)offsetof(Vertex, loc));
-  glEnableVertexAttribArray(g_positionLoc);
-  glVertexAttribPointer(g_texCoordLoc,
-                        2,
-                        GL_FLOAT,
-                        GL_FALSE,
-                        sizeof(Vertex),
-                        (void*)offsetof(Vertex, tu));
-  glEnableVertexAttribArray(g_texCoordLoc);
-  glVertexAttribPointer(g_colorLoc,
-                        3,
-                        GL_FLOAT,
-                        GL_FALSE,
-                        sizeof(Vertex),
-                        (void*)offsetof(Vertex, color));
-  glEnableVertexAttribArray(g_colorLoc);
-
-  glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, g_ibID);
-  glDrawElements(GL_TRIANGLES, 36, GL_UNSIGNED_BYTE, 0);
-}
-
-typedef void (*OpenCB)(void* dataPtr);
-struct OpenRequest {
-  PP_Resource loader_;
-  PP_Resource request_;
-  char* buf_;
-  void* data_;
-  int64_t size_;
-  int64_t avail_;
-  OpenCB cb_;
+const char kFragShaderSource[] =
+    "precision mediump float;\n"
+    "varying vec3 v_color;\n"
+    "varying vec2 v_texcoord;\n"
+    "uniform sampler2D u_texture;\n"
+    "void main() {\n"
+    "  gl_FragColor = texture2D(u_texture, v_texcoord);\n"
+    "  gl_FragColor += vec4(v_color, 1);\n"
+    "}\n";
+
+const char kVertexShaderSource[] =
+    "uniform mat4 u_mvp;\n"
+    "attribute vec2 a_texcoord;\n"
+    "attribute vec3 a_color;\n"
+    "attribute vec4 a_position;\n"
+    "varying vec3 v_color;\n"
+    "varying vec2 v_texcoord;\n"
+    "void main() {\n"
+    "  gl_Position = u_mvp * a_position;\n"
+    "  v_color = a_color;\n"
+    "  v_texcoord = a_texcoord;\n"
+    "}\n";
+
+struct Vertex {
+  float loc[3];
+  float color[3];
+  float tex[2];
 };
 
-void FreeRequest(OpenRequest* req) {
-  if (req) {
-    ppb_core_interface->ReleaseResource(req->request_);
-    ppb_core_interface->ReleaseResource(req->loader_);
-    free(req);
-  }
-}
-
-static void URLPartialRead(void* user_data, int mode) {
-  OpenRequest* req = (OpenRequest*)user_data;
-  int64_t total;
-  int32_t cnt;
-
-  if (mode < 0) {
-    free(req->buf_);
-    req->cb_(NULL);
-    FreeRequest(req);
-    return;
-  }
-
-  req->avail_ += mode;
-  total = req->size_ - req->avail_;
-
-  cnt = (total > LONG_MAX) ? LONG_MAX : (int32_t) total;
-  // If we still have more to do, re-issue the read.
-  if (cnt > 0) {
-    int32_t bytes = ppb_urlloader_interface->ReadResponseBody(
-        req->loader_,
-        (void*)&req->buf_[req->avail_],
-        cnt,
-        PP_MakeCompletionCallback(URLPartialRead, req));
-
-    // If the reissue completes immediately, then process it.
-    if (bytes != PP_OK_COMPLETIONPENDING) {
-      URLPartialRead(user_data, bytes);
-    }
-    return;
-  }
-
-  // Nothing left, so signal complete.
-  req->cb_(req);
-  FreeRequest(req);
-  printf("Loaded\n");
-}
-
-static void URLOpened(void* user_data, int mode) {
-  OpenRequest* req = (OpenRequest*)user_data;
-
-  int64_t cur, total;
-  int32_t cnt;
-  ppb_urlloader_interface->GetDownloadProgress(req->loader_, &cur, &total);
-
-  // If we can't preallocate the buffer because the size is unknown, then
-  // fail the load.
-  if (total == -1) {
-    req->cb_(NULL);
-    FreeRequest(req);
-    return;
-  }
-
-  // Otherwise allocate a buffer with enough space for a terminating
-  // NULL in case we need one.
-  cnt = (total > LONG_MAX) ? LONG_MAX : (int32_t) total;
-  req->buf_ = (char*)malloc(cnt + 1);
-  req->buf_[cnt] = 0;
-  req->size_ = cnt;
-  int32_t bytes = ppb_urlloader_interface->ReadResponseBody(
-      req->loader_,
-      req->buf_,
-      cnt,
-      PP_MakeCompletionCallback(URLPartialRead, req));
-
-  // Usually we are pending.
-  if (bytes == PP_OK_COMPLETIONPENDING)
-    return;
-
-  // But if we did complete the read, then dispatch the handler.
-  URLPartialRead(req, bytes);
-}
-
-void LoadURL(PP_Instance inst, const char* url, OpenCB cb, void* data) {
-  OpenRequest* req = (OpenRequest*)malloc(sizeof(OpenRequest));
-  memset(req, 0, sizeof(OpenRequest));
-
-  req->loader_ = ppb_urlloader_interface->Create(inst);
-  req->request_ = ppb_urlrequestinfo_interface->Create(inst);
-  req->cb_ = cb;
-  req->data_ = data;
-
-  if (!req->loader_ || !req->request_) {
-    cb(NULL);
-    FreeRequest(req);
-    return;
-  }
-
-  ppb_urlrequestinfo_interface->SetProperty(
-      req->request_, PP_URLREQUESTPROPERTY_URL, CStrToVar(url));
-  ppb_urlrequestinfo_interface->SetProperty(
-      req->request_, PP_URLREQUESTPROPERTY_METHOD, CStrToVar("GET"));
-  ppb_urlrequestinfo_interface->SetProperty(
-      req->request_,
-      PP_URLREQUESTPROPERTY_RECORDDOWNLOADPROGRESS,
-      PP_MakeBool(PP_TRUE));
-
-  int val = ppb_urlloader_interface->Open(
-      req->loader_, req->request_, PP_MakeCompletionCallback(URLOpened, req));
-
-  if (val != PP_OK_COMPLETIONPENDING) {
-    cb(NULL);
-    free(req);
-  }
-}
-
-void Loaded(void* data) {
-  OpenRequest* req = (OpenRequest*)data;
-  if (req && req->buf_) {
-    char** pptr = (char**)req->data_;
-    *pptr = req->buf_;
-    g_LoadCnt++;
-    return;
-  }
-  PostMessage("Failed to load asset.\n");
-}
-
-/**
- * Called when the NaCl module is instantiated on the web page. The identifier
- * of the new instance will be passed in as the first argument (this value is
- * generated by the browser and is an opaque handle).  This is called for each
- * instantiation of the NaCl module, which is each time the <embed> tag for
- * this module is encountered.
- *
- * If this function reports a failure (by returning @a PP_FALSE), the NaCl
- * module will be deleted and DidDestroy will be called.
- * @param[in] instance The identifier of the new instance representing this
- *     NaCl module.
- * @param[in] argc The number of arguments contained in @a argn and @a argv.
- * @param[in] argn An array of argument names.  These argument names are
- *     supplied in the <embed> tag, for example:
- *       <embed id="nacl_module" dimensions="2">
- *     will produce two arguments, one named "id" and one named "dimensions".
- * @param[in] argv An array of argument values.  These are the values of the
- *     arguments listed in the <embed> tag.  In the above example, there will
- *     be two elements in this array, "nacl_module" and "2".  The indices of
- *     these values match the indices of the corresponding names in @a argn.
- * @return @a PP_TRUE on success.
- */
-static PP_Bool Instance_DidCreate(PP_Instance instance,
-                                  uint32_t argc,
-                                  const char* argn[],
-                                  const char* argv[]) {
-  g_instance = instance;
-  LoadURL(instance, "hello.raw", Loaded, &g_TextureData);
-  LoadURL(instance, "vertex_shader_es2.vert", Loaded, &g_VShaderData);
-  LoadURL(instance, "fragment_shader_es2.frag", Loaded, &g_FShaderData);
-  g_quadVertices = BuildCube();
-  return PP_TRUE;
-}
-
-/**
- * Called when the NaCl module is destroyed. This will always be called,
- * even if DidCreate returned failure. This routine should deallocate any data
- * associated with the instance.
- * @param[in] instance The identifier of the instance representing this NaCl
- *     module.
- */
-static void Instance_DidDestroy(PP_Instance instance) {
-  delete[] g_TextureData;
-  delete[] g_VShaderData;
-  delete[] g_FShaderData;
-  delete[] g_quadVertices;
-}
-
-/**
- * Called when the position, the size, or the clip rect of the element in the
- * browser that corresponds to this NaCl module has changed.
- * @param[in] instance The identifier of the instance representing this NaCl
- *     module.
- * @param[in] position The location on the page of this NaCl module. This is
- *     relative to the top left corner of the viewport, which changes as the
- *     page is scrolled.
- * @param[in] clip The visible region of the NaCl module. This is relative to
- *     the top left of the plugin's coordinate system (not the page).  If the
- *     plugin is invisible, @a clip will be (0, 0, 0, 0).
- */
-static void Instance_DidChangeView(PP_Instance instance,
-                                   PP_Resource view_resource) {
-  if (g_context == 0) {
-    InitGL();
-    MainLoop(NULL, 0);
-  }
-}
-
-/**
- * Notification that the given NaCl module has gained or lost focus.
- * Having focus means that keyboard events will be sent to the NaCl module
- * represented by @a instance. A NaCl module's default condition is that it
- * will not have focus.
- *
- * Note: clicks on NaCl modules will give focus only if you handle the
- * click event. You signal if you handled it by returning @a true from
- * HandleInputEvent. Otherwise the browser will bubble the event and give
- * focus to the element on the page that actually did end up consuming it.
- * If you're not getting focus, check to make sure you're returning true from
- * the mouse click in HandleInputEvent.
- * @param[in] instance The identifier of the instance representing this NaCl
- *     module.
- * @param[in] has_focus Indicates whether this NaCl module gained or lost
- *     event focus.
- */
-static void Instance_DidChangeFocus(PP_Instance instance, PP_Bool has_focus) {}
-
-/**
- * Handler that gets called after a full-frame module is instantiated based on
- * registered MIME types.  This function is not called on NaCl modules.  This
- * function is essentially a place-holder for the required function pointer in
- * the PPP_Instance structure.
- * @param[in] instance The identifier of the instance representing this NaCl
- *     module.
- * @param[in] url_loader A PP_Resource an open PPB_URLLoader instance.
- * @return PP_FALSE.
- */
-static PP_Bool Instance_HandleDocumentLoad(PP_Instance instance,
-                                           PP_Resource url_loader) {
-  /* NaCl modules do not need to handle the document load function. */
-  return PP_FALSE;
-}
-
-/**
- * Entry points for the module.
- * Initialize needed interfaces: PPB_Core, PPB_Messaging and PPB_Var.
- * @param[in] a_module_id module ID
- * @param[in] get_browser pointer to PPB_GetInterface
- * @return PP_OK on success, any other value on failure.
- */
-PP_EXPORT int32_t PPP_InitializeModule(PP_Module a_module_id,
-                                       PPB_GetInterface get_browser) {
-  ppb_core_interface = (PPB_Core*)(get_browser(PPB_CORE_INTERFACE));
-  ppb_instance_interface = (PPB_Instance*)get_browser(PPB_INSTANCE_INTERFACE);
-  ppb_messaging_interface =
-      (PPB_Messaging*)(get_browser(PPB_MESSAGING_INTERFACE));
-  ppb_var_interface = (PPB_Var*)(get_browser(PPB_VAR_INTERFACE));
-  ppb_urlloader_interface =
-      (PPB_URLLoader*)(get_browser(PPB_URLLOADER_INTERFACE));
-  ppb_urlrequestinfo_interface =
-      (PPB_URLRequestInfo*)(get_browser(PPB_URLREQUESTINFO_INTERFACE));
-  ppb_g3d_interface = (PPB_Graphics3D*)get_browser(PPB_GRAPHICS_3D_INTERFACE);
-  if (!glInitializePPAPI(get_browser))
-    return PP_ERROR_FAILED;
-  return PP_OK;
-}
-
-/**
- * Returns an interface pointer for the interface of the given name, or NULL
- * if the interface is not supported.
- * @param[in] interface_name name of the interface
- * @return pointer to the interface
- */
-PP_EXPORT const void* PPP_GetInterface(const char* interface_name) {
-  if (strcmp(interface_name, PPP_INSTANCE_INTERFACE) == 0) {
-    static PPP_Instance instance_interface = {
-      &Instance_DidCreate,
-      &Instance_DidDestroy,
-      &Instance_DidChangeView,
-      &Instance_DidChangeFocus,
-      &Instance_HandleDocumentLoad,
+const Vertex kCubeVerts[24] = {
+  // +Z (red arrow, black tip)
+  {{-1.0, -1.0, +1.0}, {0.0, 0.0, 0.0}, {1.0, 0.0}},
+  {{+1.0, -1.0, +1.0}, {0.0, 0.0, 0.0}, {0.0, 0.0}},
+  {{+1.0, +1.0, +1.0}, {0.5, 0.0, 0.0}, {0.0, 1.0}},
+  {{-1.0, +1.0, +1.0}, {0.5, 0.0, 0.0}, {1.0, 1.0}},
+
+  // +X (green arrow, black tip)
+  {{+1.0, -1.0, -1.0}, {0.0, 0.0, 0.0}, {1.0, 0.0}},
+  {{+1.0, +1.0, -1.0}, {0.0, 0.0, 0.0}, {0.0, 0.0}},
+  {{+1.0, +1.0, +1.0}, {0.0, 0.5, 0.0}, {0.0, 1.0}},
+  {{+1.0, -1.0, +1.0}, {0.0, 0.5, 0.0}, {1.0, 1.0}},
+
+  // +Y (blue arrow, black tip)
+  {{-1.0, +1.0, -1.0}, {0.0, 0.0, 0.0}, {1.0, 0.0}},
+  {{-1.0, +1.0, +1.0}, {0.0, 0.0, 0.0}, {0.0, 0.0}},
+  {{+1.0, +1.0, +1.0}, {0.0, 0.0, 0.5}, {0.0, 1.0}},
+  {{+1.0, +1.0, -1.0}, {0.0, 0.0, 0.5}, {1.0, 1.0}},
+
+  // -Z (red arrow, red tip)
+  {{+1.0, +1.0, -1.0}, {0.0, 0.0, 0.0}, {1.0, 1.0}},
+  {{-1.0, +1.0, -1.0}, {0.0, 0.0, 0.0}, {0.0, 1.0}},
+  {{-1.0, -1.0, -1.0}, {1.0, 0.0, 0.0}, {0.0, 0.0}},
+  {{+1.0, -1.0, -1.0}, {1.0, 0.0, 0.0}, {1.0, 0.0}},
+
+  // -X (green arrow, green tip)
+  {{-1.0, +1.0, +1.0}, {0.0, 0.0, 0.0}, {1.0, 1.0}},
+  {{-1.0, -1.0, +1.0}, {0.0, 0.0, 0.0}, {0.0, 1.0}},
+  {{-1.0, -1.0, -1.0}, {0.0, 1.0, 0.0}, {0.0, 0.0}},
+  {{-1.0, +1.0, -1.0}, {0.0, 1.0, 0.0}, {1.0, 0.0}},
+
+  // -Y (blue arrow, blue tip)
+  {{+1.0, -1.0, +1.0}, {0.0, 0.0, 0.0}, {1.0, 1.0}},
+  {{+1.0, -1.0, -1.0}, {0.0, 0.0, 0.0}, {0.0, 1.0}},
+  {{-1.0, -1.0, -1.0}, {0.0, 0.0, 1.0}, {0.0, 0.0}},
+  {{-1.0, -1.0, +1.0}, {0.0, 0.0, 1.0}, {1.0, 0.0}},
+};
+
+const GLubyte kCubeIndexes[36] = {
+   2,  1,  0,  3,  2,  0,
+   6,  5,  4,  7,  6,  4,
+  10,  9,  8, 11, 10,  8,
+  14, 13, 12, 15, 14, 12,
+  18, 17, 16, 19, 18, 16,
+  22, 21, 20, 23, 22, 20,
+};
+
+}  // namespace
+
+
+class Graphics3DInstance : public pp::Instance {
+ public:
+  explicit Graphics3DInstance(PP_Instance instance)
+      : pp::Instance(instance),
+        callback_factory_(this),
+        width_(0),
+        height_(0),
+        frag_shader_(0),
+        vertex_shader_(0),
+        program_(0),
+        texture_loc_(0),
+        position_loc_(0),
+        color_loc_(0),
+        mvp_loc_(0),
+        x_angle_(0),
+        y_angle_(0),
+        animating_(true) {}
+
+  virtual bool Init(uint32_t argc, const char* argn[], const char* argv[]) {
+    return true;
+  }
+
+  virtual void DidChangeView(const pp::View& view) {
+    int32_t new_width = view.GetRect().width();
+    int32_t new_height = view.GetRect().height();
+
+    if (context_.is_null()) {
+      if (!InitGL(new_width, new_height)) {
+        // failed.
+        return;
+      }
+
+      InitShaders();
+      InitBuffers();
+      InitTexture();
+      MainLoop(0);
+    } else {
+      // Resize the buffers to the new size of the module.
+      int32_t result = context_.ResizeBuffers(new_width, new_height);
+      if (result < 0) {
+        fprintf(stderr,
+                "Unable to resize buffers to %d x %d!\n",
+                new_width,
+                new_height);
+        return;
+      }
+    }
+
+    width_ = new_width;
+    height_ = new_height;
+    glViewport(0, 0, width_, height_);
+  }
+
+  virtual void HandleMessage(const pp::Var& message) {
+    // A bool message sets whether the cube is animating or not.
+    if (message.is_bool()) {
+      animating_ = message.AsBool();
+      return;
+    }
+
+    // An array message sets the current x and y rotation.
+    if (!message.is_array()) {
+      fprintf(stderr, "Expected array message.\n");
+      return;
+    }
+
+    pp::VarArray array(message);
+    if (array.GetLength() != 2) {
+      fprintf(stderr, "Expected array of length 2.\n");
+      return;
+    }
+
+    pp::Var x_angle_var = array.Get(0);
+    if (x_angle_var.is_int()) {
+      x_angle_ = x_angle_var.AsInt();
+    } else if (x_angle_var.is_double()) {
+      x_angle_ = x_angle_var.AsDouble();
+    } else {
+      fprintf(stderr, "Expected value to be an int or double.\n");
+    }
+
+    pp::Var y_angle_var = array.Get(1);
+    if (y_angle_var.is_int()) {
+      y_angle_ = y_angle_var.AsInt();
+    } else if (y_angle_var.is_double()) {
+      y_angle_ = y_angle_var.AsDouble();
+    } else {
+      fprintf(stderr, "Expected value to be an int or double.\n");
+    }
+  }
+
+ private:
+  bool InitGL(int32_t new_width, int32_t new_height) {
+    if (!glInitializePPAPI(pp::Module::Get()->get_browser_interface())) {
+      fprintf(stderr, "Unable to initialize GL PPAPI!\n");
+      return false;
+    }
+
+    const int32_t attrib_list[] = {
+      PP_GRAPHICS3DATTRIB_ALPHA_SIZE, 8,
+      PP_GRAPHICS3DATTRIB_DEPTH_SIZE, 24,
+      PP_GRAPHICS3DATTRIB_WIDTH, new_width,
+      PP_GRAPHICS3DATTRIB_HEIGHT, new_height,
+      PP_GRAPHICS3DATTRIB_NONE
     };
-    return &instance_interface;
-  }
-  return NULL;
-}
-
-/**
- * Called before the plugin module is unloaded.
- */
-PP_EXPORT void PPP_ShutdownModule() {}
+
+    context_ = pp::Graphics3D(this, attrib_list);
+    if (!BindGraphics(context_)) {
+      fprintf(stderr, "Unable to bind 3d context!\n");
+      context_ = pp::Graphics3D();
+      glSetCurrentContextPPAPI(0);
+      return false;
+    }
+
+    glSetCurrentContextPPAPI(context_.pp_resource());
+    return true;
+  }
+
+  void InitShaders() {
+    frag_shader_ = CompileShader(GL_FRAGMENT_SHADER, kFragShaderSource);
+    if (!frag_shader_)
+      return;
+
+    vertex_shader_ = CompileShader(GL_VERTEX_SHADER, kVertexShaderSource);
+    if (!vertex_shader_)
+      return;
+
+    program_ = LinkProgram(frag_shader_, vertex_shader_);
+    if (!program_)
+      return;
+
+    texture_loc_ = glGetUniformLocation(program_, "u_texture");
+    position_loc_ = glGetAttribLocation(program_, "a_position");
+    texcoord_loc_ = glGetAttribLocation(program_, "a_texcoord");
+    color_loc_ = glGetAttribLocation(program_, "a_color");
+    mvp_loc_ = glGetUniformLocation(program_, "u_mvp");
+  }
+
+  void InitBuffers() {
+    glGenBuffers(1, &vertex_buffer_);
+    glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer_);
+    glBufferData(GL_ARRAY_BUFFER, sizeof(kCubeVerts), &kCubeVerts[0],
+                 GL_STATIC_DRAW);
+
+    glGenBuffers(1, &index_buffer_);
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_buffer_);
+    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(kCubeIndexes),
+                 &kCubeIndexes[0], GL_STATIC_DRAW);
+  }
+
+  void InitTexture() {
+    DecompressTexture();
+    glGenTextures(1, &texture_);
+    glBindTexture(GL_TEXTURE_2D, texture_);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D,
+                 0,
+                 GL_RGB,
+                 128,
+                 128,
+                 0,
+                 GL_RGB,
+                 GL_UNSIGNED_BYTE,
+                 &g_texture_data[0]);
+  }
+
+  void Animate() {
+    if (animating_) {
+      x_angle_ = fmod(360.0f + x_angle_ + kXAngleDelta, 360.0f);
+      y_angle_ = fmod(360.0f + y_angle_ + kYAngleDelta, 360.0f);
+
+      // Send new values to JavaScript.
+      pp::VarArray array;
+      array.SetLength(2);
+      array.Set(0, x_angle_);
+      array.Set(1, y_angle_);
+      PostMessage(array);
+    }
+  }
+
+  void Render() {
+    glClearColor(0.5, 0.5, 0.5, 1);
+    glClearDepthf(1.0f);
+    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+    glEnable(GL_DEPTH_TEST);
+
+    //set what program to use
+    glUseProgram(program_);
+    glActiveTexture(GL_TEXTURE0);
+    glBindTexture(GL_TEXTURE_2D, texture_);
+    glUniform1i(texture_loc_, 0);
+
+    //create our perspective matrix
+    float mvp[16];
+    float trs[16];
+    float rot[16];
+
+    identity_matrix(mvp);
+    const float aspect_ratio = static_cast<float>(width_) / height_;
+    glhPerspectivef2(&mvp[0], kFovY, aspect_ratio, kZNear, kZFar);
+
+    translate_matrix(0, 0, kCameraZ, trs);
+    rotate_matrix(x_angle_, y_angle_, 0.0f, rot);
+    multiply_matrix(trs, rot, trs);
+    multiply_matrix(mvp, trs, mvp);
+    glUniformMatrix4fv(mvp_loc_, 1, GL_FALSE, mvp);
+
+    //define the attributes of the vertex
+    glBindBuffer(GL_ARRAY_BUFFER, vertex_buffer_);
+    glVertexAttribPointer(position_loc_,
+                          3,
+                          GL_FLOAT,
+                          GL_FALSE,
+                          sizeof(Vertex),
+                          reinterpret_cast<void*>(offsetof(Vertex, loc)));
+    glEnableVertexAttribArray(position_loc_);
+    glVertexAttribPointer(color_loc_,
+                          3,
+                          GL_FLOAT,
+                          GL_FALSE,
+                          sizeof(Vertex),
+                          reinterpret_cast<void*>(offsetof(Vertex, color)));
+    glEnableVertexAttribArray(color_loc_);
+    glVertexAttribPointer(texcoord_loc_,
+                          2,
+                          GL_FLOAT,
+                          GL_FALSE,
+                          sizeof(Vertex),
+                          reinterpret_cast<void*>(offsetof(Vertex, tex)));
+    glEnableVertexAttribArray(texcoord_loc_);
+
+    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, index_buffer_);
+    glDrawElements(GL_TRIANGLES, 36, GL_UNSIGNED_BYTE, 0);
+  }
+
+  void MainLoop(int32_t) {
+    Animate();
+    Render();
+    context_.SwapBuffers(
+        callback_factory_.NewCallback(&Graphics3DInstance::MainLoop));
+  }
+
+  pp::CompletionCallbackFactory<Graphics3DInstance> callback_factory_;
+  pp::Graphics3D context_;
+  int32_t width_;
+  int32_t height_;
+  GLuint frag_shader_;
+  GLuint vertex_shader_;
+  GLuint program_;
+  GLuint vertex_buffer_;
+  GLuint index_buffer_;
+  GLuint texture_;
+
+  GLuint texture_loc_;
+  GLuint position_loc_;
+  GLuint texcoord_loc_;
+  GLuint color_loc_;
+  GLuint mvp_loc_;
+
+  float x_angle_;
+  float y_angle_;
+  bool animating_;
+};
+
+class Graphics3DModule : public pp::Module {
+ public:
+  Graphics3DModule() : pp::Module() {}
+  virtual ~Graphics3DModule() {}
+
+  virtual pp::Instance* CreateInstance(PP_Instance instance) {
+    return new Graphics3DInstance(instance);
+  }
+};
+
+namespace pp {
+Module* CreateModule() { return new Graphics3DModule(); }
+}  // namespace pp