1// Copyright (c) 2012 The Chromium Authors. All rights reserved.
2// Use of this source code is governed by a BSD-style license that can be
3// found in the LICENSE file.
4
5#include <string.h>
6
7#include <iostream>
8#include <sstream>
9#include <list>
10#include <map>
11#include <set>
12#include <vector>
13
14#include "ppapi/c/pp_errors.h"
15#include "ppapi/c/ppb_console.h"
16#include "ppapi/c/ppb_opengles2.h"
17#include "ppapi/cpp/dev/video_decoder_client_dev.h"
18#include "ppapi/cpp/dev/video_decoder_dev.h"
19#include "ppapi/cpp/graphics_3d.h"
20#include "ppapi/cpp/graphics_3d_client.h"
21#include "ppapi/cpp/instance.h"
22#include "ppapi/cpp/module.h"
23#include "ppapi/cpp/rect.h"
24#include "ppapi/cpp/var.h"
25#include "ppapi/examples/video_decode/testdata.h"
26#include "ppapi/lib/gl/include/GLES2/gl2.h"
27#include "ppapi/lib/gl/include/GLES2/gl2ext.h"
28#include "ppapi/utility/completion_callback_factory.h"
29
30// Use assert as a poor-man's CHECK, even in non-debug mode.
31// Since <assert.h> redefines assert on every inclusion (it doesn't use
32// include-guards), make sure this is the last file #include'd in this file.
33#undef NDEBUG
34#include <assert.h>
35
36// Assert |context_| isn't holding any GL Errors.  Done as a macro instead of a
37// function to preserve line number information in the failure message.
38#define assertNoGLError() \
39  assert(!gles2_if_->GetError(context_->pp_resource()));
40
41namespace {
42
43struct PictureBufferInfo {
44  PP_PictureBuffer_Dev buffer;
45  GLenum texture_target;
46};
47
48struct Shader {
49  Shader() : program(0),
50             texcoord_scale_location(0) {}
51
52  GLuint program;
53  GLint texcoord_scale_location;
54};
55
56class VideoDecodeDemoInstance : public pp::Instance,
57                                public pp::Graphics3DClient,
58                                public pp::VideoDecoderClient_Dev {
59 public:
60  VideoDecodeDemoInstance(PP_Instance instance, pp::Module* module);
61  virtual ~VideoDecodeDemoInstance();
62
63  // pp::Instance implementation (see PPP_Instance).
64  virtual void DidChangeView(const pp::Rect& position,
65                             const pp::Rect& clip_ignored);
66
67  // pp::Graphics3DClient implementation.
68  virtual void Graphics3DContextLost() {
69    // TODO(vrk/fischman): Properly reset after a lost graphics context.  In
70    // particular need to delete context_ and re-create textures.
71    // Probably have to recreate the decoder from scratch, because old textures
72    // can still be outstanding in the decoder!
73    assert(false && "Unexpectedly lost graphics context");
74  }
75
76  // pp::VideoDecoderClient_Dev implementation.
77  virtual void ProvidePictureBuffers(
78      PP_Resource decoder,
79      uint32_t req_num_of_bufs,
80      const PP_Size& dimensions,
81      uint32_t texture_target);
82  virtual void DismissPictureBuffer(PP_Resource decoder,
83                                    int32_t picture_buffer_id);
84  virtual void PictureReady(PP_Resource decoder, const PP_Picture_Dev& picture);
85  virtual void NotifyError(PP_Resource decoder, PP_VideoDecodeError_Dev error);
86
87 private:
88  enum { kNumConcurrentDecodes = 7,
89         kNumDecoders = 2 };  // Baked into viewport rendering.
90
91  // A single decoder's client interface.
92  class DecoderClient {
93   public:
94    DecoderClient(VideoDecodeDemoInstance* gles2,
95                  pp::VideoDecoder_Dev* decoder);
96    ~DecoderClient();
97
98    void DecodeNextNALUs();
99
100    // Per-decoder implementation of part of pp::VideoDecoderClient_Dev.
101    void ProvidePictureBuffers(
102        uint32_t req_num_of_bufs,
103        PP_Size dimensions,
104        uint32_t texture_target);
105    void DismissPictureBuffer(int32_t picture_buffer_id);
106
107    const PictureBufferInfo& GetPictureBufferInfoById(int id);
108    pp::VideoDecoder_Dev* decoder() { return decoder_; }
109
110   private:
111    void DecodeNextNALU();
112    static void GetNextNALUBoundary(size_t start_pos, size_t* end_pos);
113    void DecoderBitstreamDone(int32_t result, int bitstream_buffer_id);
114    void DecoderFlushDone(int32_t result);
115
116    VideoDecodeDemoInstance* gles2_;
117    pp::VideoDecoder_Dev* decoder_;
118    pp::CompletionCallbackFactory<DecoderClient> callback_factory_;
119    int next_picture_buffer_id_;
120    int next_bitstream_buffer_id_;
121    size_t encoded_data_next_pos_to_decode_;
122    std::set<int> bitstream_ids_at_decoder_;
123    // Map of texture buffers indexed by buffer id.
124    typedef std::map<int, PictureBufferInfo> PictureBufferMap;
125    PictureBufferMap picture_buffers_by_id_;
126    // Map of bitstream buffers indexed by id.
127    typedef std::map<int, pp::Buffer_Dev*> BitstreamBufferMap;
128    BitstreamBufferMap bitstream_buffers_by_id_;
129  };
130
131  // Initialize Video Decoders.
132  void InitializeDecoders();
133
134  // GL-related functions.
135  void InitGL();
136  GLuint CreateTexture(int32_t width, int32_t height, GLenum texture_target);
137  void CreateGLObjects();
138  void Create2DProgramOnce();
139  void CreateRectangleARBProgramOnce();
140  Shader CreateProgram(const char* vertex_shader,
141                       const char* fragment_shader);
142  void CreateShader(GLuint program, GLenum type, const char* source, int size);
143  void DeleteTexture(GLuint id);
144  void PaintFinished(int32_t result, PP_Resource decoder,
145                     int picture_buffer_id);
146
147  // Log an error to the developer console and stderr (though the latter may be
148  // closed due to sandboxing or blackholed for other reasons) by creating a
149  // temporary of this type and streaming to it.  Example usage:
150  // LogError(this).s() << "Hello world: " << 42;
151  class LogError {
152   public:
153    LogError(VideoDecodeDemoInstance* demo) : demo_(demo) {}
154    ~LogError() {
155      const std::string& msg = stream_.str();
156      demo_->console_if_->Log(demo_->pp_instance(), PP_LOGLEVEL_ERROR,
157                              pp::Var(msg).pp_var());
158      std::cerr << msg << std::endl;
159    }
160    // Impl note: it would have been nicer to have LogError derive from
161    // std::ostringstream so that it can be streamed to directly, but lookup
162    // rules turn streamed string literals to hex pointers on output.
163    std::ostringstream& s() { return stream_; }
164   private:
165    VideoDecodeDemoInstance* demo_;  // Unowned.
166    std::ostringstream stream_;
167  };
168
169  pp::Size plugin_size_;
170  bool is_painting_;
171  // When decode outpaces render, we queue up decoded pictures for later
172  // painting.  Elements are <decoder,picture>.
173  std::list<std::pair<PP_Resource, PP_Picture_Dev> > pictures_pending_paint_;
174  int num_frames_rendered_;
175  PP_TimeTicks first_frame_delivered_ticks_;
176  PP_TimeTicks last_swap_request_ticks_;
177  PP_TimeTicks swap_ticks_;
178  pp::CompletionCallbackFactory<VideoDecodeDemoInstance> callback_factory_;
179
180  // Unowned pointers.
181  const PPB_Console* console_if_;
182  const PPB_Core* core_if_;
183  const PPB_OpenGLES2* gles2_if_;
184
185  // Owned data.
186  pp::Graphics3D* context_;
187  typedef std::map<int, DecoderClient*> Decoders;
188  Decoders video_decoders_;
189
190  // Shader program to draw GL_TEXTURE_2D target.
191  Shader shader_2d_;
192  // Shader program to draw GL_TEXTURE_RECTANGLE_ARB target.
193  Shader shader_rectangle_arb_;
194};
195
196VideoDecodeDemoInstance::DecoderClient::DecoderClient(
197      VideoDecodeDemoInstance* gles2, pp::VideoDecoder_Dev* decoder)
198    : gles2_(gles2), decoder_(decoder), callback_factory_(this),
199      next_picture_buffer_id_(0),
200      next_bitstream_buffer_id_(0), encoded_data_next_pos_to_decode_(0) {
201}
202
203VideoDecodeDemoInstance::DecoderClient::~DecoderClient() {
204  delete decoder_;
205  decoder_ = NULL;
206
207  for (BitstreamBufferMap::iterator it = bitstream_buffers_by_id_.begin();
208       it != bitstream_buffers_by_id_.end(); ++it) {
209    delete it->second;
210  }
211  bitstream_buffers_by_id_.clear();
212
213  for (PictureBufferMap::iterator it = picture_buffers_by_id_.begin();
214       it != picture_buffers_by_id_.end(); ++it) {
215    gles2_->DeleteTexture(it->second.buffer.texture_id);
216  }
217  picture_buffers_by_id_.clear();
218}
219
220VideoDecodeDemoInstance::VideoDecodeDemoInstance(PP_Instance instance,
221                                                 pp::Module* module)
222    : pp::Instance(instance), pp::Graphics3DClient(this),
223      pp::VideoDecoderClient_Dev(this),
224      num_frames_rendered_(0),
225      first_frame_delivered_ticks_(-1),
226      swap_ticks_(0),
227      callback_factory_(this),
228      context_(NULL) {
229  assert((console_if_ = static_cast<const PPB_Console*>(
230      module->GetBrowserInterface(PPB_CONSOLE_INTERFACE))));
231  assert((core_if_ = static_cast<const PPB_Core*>(
232      module->GetBrowserInterface(PPB_CORE_INTERFACE))));
233  assert((gles2_if_ = static_cast<const PPB_OpenGLES2*>(
234      module->GetBrowserInterface(PPB_OPENGLES2_INTERFACE))));
235}
236
237VideoDecodeDemoInstance::~VideoDecodeDemoInstance() {
238  if (shader_2d_.program)
239    gles2_if_->DeleteProgram(context_->pp_resource(), shader_2d_.program);
240  if (shader_rectangle_arb_.program) {
241    gles2_if_->DeleteProgram(
242        context_->pp_resource(), shader_rectangle_arb_.program);
243  }
244
245  for (Decoders::iterator it = video_decoders_.begin();
246       it != video_decoders_.end(); ++it) {
247    delete it->second;
248  }
249  video_decoders_.clear();
250  delete context_;
251}
252
253void VideoDecodeDemoInstance::DidChangeView(
254    const pp::Rect& position, const pp::Rect& clip_ignored) {
255  if (position.width() == 0 || position.height() == 0)
256    return;
257  if (plugin_size_.width()) {
258    assert(position.size() == plugin_size_);
259    return;
260  }
261  plugin_size_ = position.size();
262
263  // Initialize graphics.
264  InitGL();
265  InitializeDecoders();
266}
267
268void VideoDecodeDemoInstance::InitializeDecoders() {
269  assert(video_decoders_.empty());
270  for (int i = 0; i < kNumDecoders; ++i) {
271    DecoderClient* client = new DecoderClient(
272        this, new pp::VideoDecoder_Dev(
273            this, *context_, PP_VIDEODECODER_H264PROFILE_MAIN));
274    assert(!client->decoder()->is_null());
275    assert(video_decoders_.insert(std::make_pair(
276        client->decoder()->pp_resource(), client)).second);
277    client->DecodeNextNALUs();
278  }
279}
280
281void VideoDecodeDemoInstance::DecoderClient::DecoderBitstreamDone(
282    int32_t result, int bitstream_buffer_id) {
283  assert(bitstream_ids_at_decoder_.erase(bitstream_buffer_id) == 1);
284  BitstreamBufferMap::iterator it =
285      bitstream_buffers_by_id_.find(bitstream_buffer_id);
286  assert(it != bitstream_buffers_by_id_.end());
287  delete it->second;
288  bitstream_buffers_by_id_.erase(it);
289  DecodeNextNALUs();
290}
291
292void VideoDecodeDemoInstance::DecoderClient::DecoderFlushDone(int32_t result) {
293  assert(result == PP_OK);
294  // Check that each bitstream buffer ID we handed to the decoder got handed
295  // back to us.
296  assert(bitstream_ids_at_decoder_.empty());
297  delete decoder_;
298  decoder_ = NULL;
299}
300
301static bool LookingAtNAL(const unsigned char* encoded, size_t pos) {
302  return pos + 3 < kDataLen &&
303      encoded[pos] == 0 && encoded[pos + 1] == 0 &&
304      encoded[pos + 2] == 0 && encoded[pos + 3] == 1;
305}
306
307void VideoDecodeDemoInstance::DecoderClient::GetNextNALUBoundary(
308    size_t start_pos, size_t* end_pos) {
309  assert(LookingAtNAL(kData, start_pos));
310  *end_pos = start_pos;
311  *end_pos += 4;
312  while (*end_pos + 3 < kDataLen &&
313         !LookingAtNAL(kData, *end_pos)) {
314    ++*end_pos;
315  }
316  if (*end_pos + 3 >= kDataLen) {
317    *end_pos = kDataLen;
318    return;
319  }
320}
321
322void VideoDecodeDemoInstance::DecoderClient::DecodeNextNALUs() {
323  while (encoded_data_next_pos_to_decode_ <= kDataLen &&
324         bitstream_ids_at_decoder_.size() < kNumConcurrentDecodes) {
325    DecodeNextNALU();
326  }
327}
328
329void VideoDecodeDemoInstance::DecoderClient::DecodeNextNALU() {
330  if (encoded_data_next_pos_to_decode_ == kDataLen) {
331    ++encoded_data_next_pos_to_decode_;
332    pp::CompletionCallback cb = callback_factory_.NewCallback(
333        &VideoDecodeDemoInstance::DecoderClient::DecoderFlushDone);
334    decoder_->Flush(cb);
335    return;
336  }
337  size_t start_pos = encoded_data_next_pos_to_decode_;
338  size_t end_pos;
339  GetNextNALUBoundary(start_pos, &end_pos);
340  pp::Buffer_Dev* buffer = new pp::Buffer_Dev(gles2_, end_pos - start_pos);
341  PP_VideoBitstreamBuffer_Dev bitstream_buffer;
342  int id = ++next_bitstream_buffer_id_;
343  bitstream_buffer.id = id;
344  bitstream_buffer.size = end_pos - start_pos;
345  bitstream_buffer.data = buffer->pp_resource();
346  memcpy(buffer->data(), kData + start_pos, end_pos - start_pos);
347  assert(bitstream_buffers_by_id_.insert(std::make_pair(id, buffer)).second);
348
349  pp::CompletionCallback cb =
350      callback_factory_.NewCallback(
351          &VideoDecodeDemoInstance::DecoderClient::DecoderBitstreamDone, id);
352  assert(bitstream_ids_at_decoder_.insert(id).second);
353  encoded_data_next_pos_to_decode_ = end_pos;
354  decoder_->Decode(bitstream_buffer, cb);
355}
356
357void VideoDecodeDemoInstance::ProvidePictureBuffers(PP_Resource decoder,
358                                                    uint32_t req_num_of_bufs,
359                                                    const PP_Size& dimensions,
360                                                    uint32_t texture_target) {
361  DecoderClient* client = video_decoders_[decoder];
362  assert(client);
363  client->ProvidePictureBuffers(req_num_of_bufs, dimensions, texture_target);
364}
365
366void VideoDecodeDemoInstance::DecoderClient::ProvidePictureBuffers(
367    uint32_t req_num_of_bufs,
368    PP_Size dimensions,
369    uint32_t texture_target) {
370  std::vector<PP_PictureBuffer_Dev> buffers;
371  for (uint32_t i = 0; i < req_num_of_bufs; ++i) {
372    PictureBufferInfo info;
373    info.buffer.size = dimensions;
374    info.texture_target = texture_target;
375    info.buffer.texture_id = gles2_->CreateTexture(
376        dimensions.width, dimensions.height, info.texture_target);
377    int id = ++next_picture_buffer_id_;
378    info.buffer.id = id;
379    buffers.push_back(info.buffer);
380    assert(picture_buffers_by_id_.insert(std::make_pair(id, info)).second);
381  }
382  decoder_->AssignPictureBuffers(buffers);
383}
384
385const PictureBufferInfo&
386VideoDecodeDemoInstance::DecoderClient::GetPictureBufferInfoById(
387    int id) {
388  PictureBufferMap::iterator it = picture_buffers_by_id_.find(id);
389  assert(it != picture_buffers_by_id_.end());
390  return it->second;
391}
392
393void VideoDecodeDemoInstance::DismissPictureBuffer(PP_Resource decoder,
394                                             int32_t picture_buffer_id) {
395  DecoderClient* client = video_decoders_[decoder];
396  assert(client);
397  client->DismissPictureBuffer(picture_buffer_id);
398}
399
400void VideoDecodeDemoInstance::DecoderClient::DismissPictureBuffer(
401    int32_t picture_buffer_id) {
402  gles2_->DeleteTexture(GetPictureBufferInfoById(
403      picture_buffer_id).buffer.texture_id);
404  picture_buffers_by_id_.erase(picture_buffer_id);
405}
406
407void VideoDecodeDemoInstance::PictureReady(PP_Resource decoder,
408                                     const PP_Picture_Dev& picture) {
409  if (first_frame_delivered_ticks_ == -1)
410    assert((first_frame_delivered_ticks_ = core_if_->GetTimeTicks()) != -1);
411  if (is_painting_) {
412    pictures_pending_paint_.push_back(std::make_pair(decoder, picture));
413    return;
414  }
415  DecoderClient* client = video_decoders_[decoder];
416  assert(client);
417  const PictureBufferInfo& info =
418      client->GetPictureBufferInfoById(picture.picture_buffer_id);
419  assert(!is_painting_);
420  is_painting_ = true;
421  int x = 0;
422  int y = 0;
423  if (client != video_decoders_.begin()->second) {
424    x = plugin_size_.width() / kNumDecoders;
425    y = plugin_size_.height() / kNumDecoders;
426  }
427
428  if (info.texture_target == GL_TEXTURE_2D) {
429    Create2DProgramOnce();
430    gles2_if_->UseProgram(context_->pp_resource(), shader_2d_.program);
431    gles2_if_->Uniform2f(
432        context_->pp_resource(), shader_2d_.texcoord_scale_location, 1.0, 1.0);
433  } else {
434    assert(info.texture_target == GL_TEXTURE_RECTANGLE_ARB);
435    CreateRectangleARBProgramOnce();
436    gles2_if_->UseProgram(
437        context_->pp_resource(), shader_rectangle_arb_.program);
438    gles2_if_->Uniform2f(context_->pp_resource(),
439                         shader_rectangle_arb_.texcoord_scale_location,
440                         info.buffer.size.width,
441                         info.buffer.size.height);
442  }
443
444  gles2_if_->Viewport(context_->pp_resource(), x, y,
445                      plugin_size_.width() / kNumDecoders,
446                      plugin_size_.height() / kNumDecoders);
447  gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE0);
448  gles2_if_->BindTexture(
449      context_->pp_resource(), info.texture_target, info.buffer.texture_id);
450  gles2_if_->DrawArrays(context_->pp_resource(), GL_TRIANGLE_STRIP, 0, 4);
451
452  gles2_if_->UseProgram(context_->pp_resource(), 0);
453
454  pp::CompletionCallback cb =
455      callback_factory_.NewCallback(
456          &VideoDecodeDemoInstance::PaintFinished, decoder, info.buffer.id);
457  last_swap_request_ticks_ = core_if_->GetTimeTicks();
458  assert(context_->SwapBuffers(cb) == PP_OK_COMPLETIONPENDING);
459}
460
461void VideoDecodeDemoInstance::NotifyError(PP_Resource decoder,
462                                          PP_VideoDecodeError_Dev error) {
463  LogError(this).s() << "Received error: " << error;
464  assert(false && "Unexpected error; see stderr for details");
465}
466
467// This object is the global object representing this plugin library as long
468// as it is loaded.
469class VideoDecodeDemoModule : public pp::Module {
470 public:
471  VideoDecodeDemoModule() : pp::Module() {}
472  virtual ~VideoDecodeDemoModule() {}
473
474  virtual pp::Instance* CreateInstance(PP_Instance instance) {
475    return new VideoDecodeDemoInstance(instance, this);
476  }
477};
478
479void VideoDecodeDemoInstance::InitGL() {
480  assert(plugin_size_.width() && plugin_size_.height());
481  is_painting_ = false;
482
483  assert(!context_);
484  int32_t context_attributes[] = {
485    PP_GRAPHICS3DATTRIB_ALPHA_SIZE, 8,
486    PP_GRAPHICS3DATTRIB_BLUE_SIZE, 8,
487    PP_GRAPHICS3DATTRIB_GREEN_SIZE, 8,
488    PP_GRAPHICS3DATTRIB_RED_SIZE, 8,
489    PP_GRAPHICS3DATTRIB_DEPTH_SIZE, 0,
490    PP_GRAPHICS3DATTRIB_STENCIL_SIZE, 0,
491    PP_GRAPHICS3DATTRIB_SAMPLES, 0,
492    PP_GRAPHICS3DATTRIB_SAMPLE_BUFFERS, 0,
493    PP_GRAPHICS3DATTRIB_WIDTH, plugin_size_.width(),
494    PP_GRAPHICS3DATTRIB_HEIGHT, plugin_size_.height(),
495    PP_GRAPHICS3DATTRIB_NONE,
496  };
497  context_ = new pp::Graphics3D(this, context_attributes);
498  assert(!context_->is_null());
499  assert(BindGraphics(*context_));
500
501  // Clear color bit.
502  gles2_if_->ClearColor(context_->pp_resource(), 1, 0, 0, 1);
503  gles2_if_->Clear(context_->pp_resource(), GL_COLOR_BUFFER_BIT);
504
505  assertNoGLError();
506
507  CreateGLObjects();
508}
509
510void VideoDecodeDemoInstance::PaintFinished(int32_t result, PP_Resource decoder,
511                                      int picture_buffer_id) {
512  assert(result == PP_OK);
513  swap_ticks_ += core_if_->GetTimeTicks() - last_swap_request_ticks_;
514  is_painting_ = false;
515  ++num_frames_rendered_;
516  if (num_frames_rendered_ % 50 == 0) {
517    double elapsed = core_if_->GetTimeTicks() - first_frame_delivered_ticks_;
518    double fps = (elapsed > 0) ? num_frames_rendered_ / elapsed : 1000;
519    double ms_per_swap = (swap_ticks_ * 1e3) / num_frames_rendered_;
520    LogError(this).s() << "Rendered frames: " << num_frames_rendered_
521                       << ", fps: " << fps << ", with average ms/swap of: "
522                       << ms_per_swap;
523  }
524  DecoderClient* client = video_decoders_[decoder];
525  if (client && client->decoder())
526    client->decoder()->ReusePictureBuffer(picture_buffer_id);
527  if (!pictures_pending_paint_.empty()) {
528    std::pair<PP_Resource, PP_Picture_Dev> decoder_picture =
529        pictures_pending_paint_.front();
530    pictures_pending_paint_.pop_front();
531    PictureReady(decoder_picture.first, decoder_picture.second);
532  }
533}
534
535GLuint VideoDecodeDemoInstance::CreateTexture(int32_t width,
536                                              int32_t height,
537                                              GLenum texture_target) {
538  GLuint texture_id;
539  gles2_if_->GenTextures(context_->pp_resource(), 1, &texture_id);
540  assertNoGLError();
541  // Assign parameters.
542  gles2_if_->ActiveTexture(context_->pp_resource(), GL_TEXTURE0);
543  gles2_if_->BindTexture(context_->pp_resource(), texture_target, texture_id);
544  gles2_if_->TexParameteri(
545      context_->pp_resource(), texture_target, GL_TEXTURE_MIN_FILTER,
546      GL_NEAREST);
547  gles2_if_->TexParameteri(
548      context_->pp_resource(), texture_target, GL_TEXTURE_MAG_FILTER,
549      GL_NEAREST);
550  gles2_if_->TexParameterf(
551      context_->pp_resource(), texture_target, GL_TEXTURE_WRAP_S,
552      GL_CLAMP_TO_EDGE);
553  gles2_if_->TexParameterf(
554      context_->pp_resource(), texture_target, GL_TEXTURE_WRAP_T,
555      GL_CLAMP_TO_EDGE);
556
557  if (texture_target == GL_TEXTURE_2D) {
558    gles2_if_->TexImage2D(
559        context_->pp_resource(), texture_target, 0, GL_RGBA, width, height, 0,
560        GL_RGBA, GL_UNSIGNED_BYTE, NULL);
561  }
562  assertNoGLError();
563  return texture_id;
564}
565
566void VideoDecodeDemoInstance::DeleteTexture(GLuint id) {
567  gles2_if_->DeleteTextures(context_->pp_resource(), 1, &id);
568}
569
570void VideoDecodeDemoInstance::CreateGLObjects() {
571  // Assign vertex positions and texture coordinates to buffers for use in
572  // shader program.
573  static const float kVertices[] = {
574    -1, 1, -1, -1, 1, 1, 1, -1,  // Position coordinates.
575    0, 1, 0, 0, 1, 1, 1, 0,      // Texture coordinates.
576  };
577
578  GLuint buffer;
579  gles2_if_->GenBuffers(context_->pp_resource(), 1, &buffer);
580  gles2_if_->BindBuffer(context_->pp_resource(), GL_ARRAY_BUFFER, buffer);
581
582  gles2_if_->BufferData(context_->pp_resource(), GL_ARRAY_BUFFER,
583                        sizeof(kVertices), kVertices, GL_STATIC_DRAW);
584  assertNoGLError();
585}
586
587static const char kVertexShader[] =
588    "varying vec2 v_texCoord;            \n"
589    "attribute vec4 a_position;          \n"
590    "attribute vec2 a_texCoord;          \n"
591    "uniform vec2 v_scale;               \n"
592    "void main()                         \n"
593    "{                                   \n"
594    "    v_texCoord = v_scale * a_texCoord; \n"
595    "    gl_Position = a_position;       \n"
596    "}";
597
598void VideoDecodeDemoInstance::Create2DProgramOnce() {
599  if (shader_2d_.program)
600    return;
601  static const char kFragmentShader2D[] =
602      "precision mediump float;            \n"
603      "varying vec2 v_texCoord;            \n"
604      "uniform sampler2D s_texture;        \n"
605      "void main()                         \n"
606      "{"
607      "    gl_FragColor = texture2D(s_texture, v_texCoord); \n"
608      "}";
609  shader_2d_ = CreateProgram(kVertexShader, kFragmentShader2D);
610  assertNoGLError();
611}
612
613void VideoDecodeDemoInstance::CreateRectangleARBProgramOnce() {
614  if (shader_rectangle_arb_.program)
615    return;
616  static const char kFragmentShaderRectangle[] =
617      "#extension GL_ARB_texture_rectangle : require\n"
618      "precision mediump float;            \n"
619      "varying vec2 v_texCoord;            \n"
620      "uniform sampler2DRect s_texture;    \n"
621      "void main()                         \n"
622      "{"
623      "    gl_FragColor = texture2DRect(s_texture, v_texCoord).rgba; \n"
624      "}";
625  shader_rectangle_arb_ =
626      CreateProgram(kVertexShader, kFragmentShaderRectangle);
627}
628
629Shader VideoDecodeDemoInstance::CreateProgram(const char* vertex_shader,
630                                              const char* fragment_shader) {
631  Shader shader;
632
633  // Create shader program.
634  shader.program = gles2_if_->CreateProgram(context_->pp_resource());
635  CreateShader(shader.program, GL_VERTEX_SHADER, vertex_shader,
636               strlen(vertex_shader));
637  CreateShader(shader.program, GL_FRAGMENT_SHADER, fragment_shader,
638               strlen(fragment_shader));
639  gles2_if_->LinkProgram(context_->pp_resource(), shader.program);
640  gles2_if_->UseProgram(context_->pp_resource(), shader.program);
641  gles2_if_->Uniform1i(
642      context_->pp_resource(),
643      gles2_if_->GetUniformLocation(
644          context_->pp_resource(), shader.program, "s_texture"), 0);
645  assertNoGLError();
646
647  shader.texcoord_scale_location = gles2_if_->GetUniformLocation(
648      context_->pp_resource(), shader.program, "v_scale");
649
650  GLint pos_location = gles2_if_->GetAttribLocation(
651      context_->pp_resource(), shader.program, "a_position");
652  GLint tc_location = gles2_if_->GetAttribLocation(
653      context_->pp_resource(), shader.program, "a_texCoord");
654  assertNoGLError();
655
656  gles2_if_->EnableVertexAttribArray(context_->pp_resource(), pos_location);
657  gles2_if_->VertexAttribPointer(context_->pp_resource(), pos_location, 2,
658                                 GL_FLOAT, GL_FALSE, 0, 0);
659  gles2_if_->EnableVertexAttribArray(context_->pp_resource(), tc_location);
660  gles2_if_->VertexAttribPointer(
661      context_->pp_resource(), tc_location, 2, GL_FLOAT, GL_FALSE, 0,
662      static_cast<float*>(0) + 8);  // Skip position coordinates.
663
664  gles2_if_->UseProgram(context_->pp_resource(), 0);
665  assertNoGLError();
666  return shader;
667}
668
669void VideoDecodeDemoInstance::CreateShader(
670    GLuint program, GLenum type, const char* source, int size) {
671  GLuint shader = gles2_if_->CreateShader(context_->pp_resource(), type);
672  gles2_if_->ShaderSource(context_->pp_resource(), shader, 1, &source, &size);
673  gles2_if_->CompileShader(context_->pp_resource(), shader);
674  gles2_if_->AttachShader(context_->pp_resource(), program, shader);
675  gles2_if_->DeleteShader(context_->pp_resource(), shader);
676}
677}  // anonymous namespace
678
679namespace pp {
680// Factory function for your specialization of the Module object.
681Module* CreateModule() {
682  return new VideoDecodeDemoModule();
683}
684}  // namespace pp
685