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2.0. Reduced frame latency by 3 frames.
[casparcg] / core / mixer / image / image_mixer.cpp
1 /*\r
2 * copyright (c) 2010 Sveriges Television AB <info@casparcg.com>\r
3 *\r
4 *  This file is part of CasparCG.\r
5 *\r
6 *    CasparCG is free software: you can redistribute it and/or modify\r
7 *    it under the terms of the GNU General Public License as published by\r
8 *    the Free Software Foundation, either version 3 of the License, or\r
9 *    (at your option) any later version.\r
10 *\r
11 *    CasparCG is distributed in the hope that it will be useful,\r
12 *    but WITHOUT ANY WARRANTY; without even the implied warranty of\r
13 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the\r
14 *    GNU General Public License for more details.\r
15 \r
16 *    You should have received a copy of the GNU General Public License\r
17 *    along with CasparCG.  If not, see <http://www.gnu.org/licenses/>.\r
18 *\r
19 */\r
20 #include "../../stdafx.h"\r
21 \r
22 #include "image_mixer.h"\r
23 #include "image_kernel.h"\r
24 \r
25 #include "../gpu/ogl_device.h"\r
26 #include "../gpu/host_buffer.h"\r
27 #include "../gpu/device_buffer.h"\r
28 #include "../write_frame.h"\r
29 \r
30 #include "../../video_channel_context.h"\r
31 \r
32 #include <common/concurrency/executor.h>\r
33 #include <common/exception/exceptions.h>\r
34 #include <common/gl/gl_check.h>\r
35 \r
36 #include <core/producer/frame/image_transform.h>\r
37 #include <core/producer/frame/pixel_format.h>\r
38 #include <core/video_format.h>\r
39 \r
40 #include <boost/foreach.hpp>\r
41 \r
42 #include <array>\r
43 #include <unordered_map>\r
44 \r
45 namespace caspar { namespace core {\r
46                 \r
47 struct image_mixer::implementation : boost::noncopyable\r
48 {       \r
49         static const size_t LOCAL_KEY_INDEX = 3;\r
50         static const size_t LAYER_KEY_INDEX = 4;\r
51 \r
52         struct render_item\r
53         {\r
54                 pixel_format_desc                                        desc;\r
55                 std::vector<safe_ptr<device_buffer>> textures;\r
56                 int                                                                      tag;\r
57                 core::image_transform                            transform;\r
58         };\r
59 \r
60         video_channel_context&                                  channel_;\r
61         \r
62         std::stack<core::image_transform>               transform_stack_;\r
63         std::queue<std::queue<render_item>>             render_queue_;\r
64         \r
65         image_kernel                                                    kernel_;\r
66                 \r
67         safe_ptr<device_buffer>                                 draw_buffer_;\r
68         safe_ptr<device_buffer>                                 write_buffer_;\r
69 \r
70         safe_ptr<device_buffer>                                 local_key_buffer_;\r
71         safe_ptr<device_buffer>                                 layer_key_buffer_;\r
72 \r
73         bool                                                                    local_key_;\r
74         bool                                                                    layer_key_;\r
75         \r
76 public:\r
77         implementation(video_channel_context& video_channel) \r
78                 : channel_(video_channel)\r
79                 , draw_buffer_(video_channel.ogl().create_device_buffer(video_channel.get_format_desc().width, channel_.get_format_desc().height, 4))\r
80                 , write_buffer_ (video_channel.ogl().create_device_buffer(video_channel.get_format_desc().width, channel_.get_format_desc().height, 4))\r
81                 , local_key_buffer_(video_channel.ogl().create_device_buffer(video_channel.get_format_desc().width, channel_.get_format_desc().height, 1))\r
82                 , layer_key_buffer_(video_channel.ogl().create_device_buffer(video_channel.get_format_desc().width, channel_.get_format_desc().height, 1))\r
83                 , local_key_(false)\r
84                 , layer_key_(false)\r
85         {\r
86                 transform_stack_.push(core::image_transform());\r
87 \r
88                 channel_.ogl().invoke([=]\r
89                 {\r
90                         if(!GLEE_VERSION_3_0)\r
91                                 CASPAR_LOG(warning) << "Missing OpenGL 3.0 support.";//BOOST_THROW_EXCEPTION(not_supported() << msg_info("Missing OpenGL 3.0 support."));\r
92                 });\r
93         }\r
94 \r
95         void begin(core::basic_frame& frame)\r
96         {\r
97                 transform_stack_.push(transform_stack_.top()*frame.get_image_transform());\r
98         }\r
99                 \r
100         void visit(core::write_frame& frame)\r
101         {                       \r
102                 render_item item = {frame.get_pixel_format_desc(), frame.get_textures(), frame.tag(), transform_stack_.top()*frame.get_image_transform()};      \r
103                 render_queue_.back().push(item);\r
104         }\r
105 \r
106         void end()\r
107         {\r
108                 transform_stack_.pop();\r
109         }\r
110 \r
111         void begin_layer()\r
112         {\r
113                 render_queue_.push(std::queue<render_item>());\r
114         }\r
115 \r
116         void end_layer()\r
117         {\r
118         }\r
119 \r
120         void reinitialize_buffers()\r
121         {\r
122                 draw_buffer_      = channel_.ogl().create_device_buffer(channel_.get_format_desc().width, channel_.get_format_desc().height, 4);\r
123                 write_buffer_     = channel_.ogl().create_device_buffer(channel_.get_format_desc().width, channel_.get_format_desc().height, 4);\r
124                 local_key_buffer_ = channel_.ogl().create_device_buffer(channel_.get_format_desc().width, channel_.get_format_desc().height, 1);\r
125                 layer_key_buffer_ = channel_.ogl().create_device_buffer(channel_.get_format_desc().width, channel_.get_format_desc().height, 1);\r
126                 channel_.ogl().gc();\r
127         }\r
128 \r
129         safe_ptr<host_buffer> render()\r
130         {               \r
131                 auto read_buffer = channel_.ogl().create_host_buffer(channel_.get_format_desc().size, host_buffer::read_only);          \r
132 \r
133                 auto render_queue = std::move(render_queue_);\r
134 \r
135                 channel_.ogl().invoke([=]() mutable\r
136                 {\r
137                         if(draw_buffer_->width() != channel_.get_format_desc().width || draw_buffer_->height() != channel_.get_format_desc().height)\r
138                                 reinitialize_buffers();\r
139 \r
140                         local_key_ = false;\r
141                         layer_key_ = false;\r
142 \r
143                         // Clear buffers.\r
144                         local_key_buffer_->clear();\r
145                         layer_key_buffer_->clear();\r
146                         draw_buffer_->clear();\r
147 \r
148                         // Draw items in device.\r
149 \r
150                         while(!render_queue.empty())\r
151                         {\r
152                                 auto layer = render_queue.front();\r
153                                 render_queue.pop();\r
154                                 \r
155                                 draw_buffer_->attach(); \r
156                                 \r
157                                 while(!layer.empty())\r
158                                 {\r
159                                         // Split layer into streams\r
160                                         std::vector<render_item> stream;\r
161                                         do\r
162                                         {\r
163                                                 stream.push_back(layer.front());\r
164                                                 layer.pop();\r
165                                         }\r
166                                         while(!layer.empty() && layer.front().tag == stream.front().tag);\r
167 \r
168                                         draw(stream);\r
169 \r
170                                         channel_.ogl().yield(); // Allow quick buffer allocation to execute.\r
171                                 }\r
172 \r
173                                 layer_key_ = local_key_; // If there was only key in last layer then use it as key for the entire next layer.\r
174                                 local_key_ = false;\r
175 \r
176                                 std::swap(local_key_buffer_, layer_key_buffer_);\r
177                         }\r
178 \r
179                         std::swap(draw_buffer_, write_buffer_);\r
180 \r
181                         // Start transfer from device to host.                          \r
182                         write_buffer_->write(*read_buffer);\r
183                 });\r
184 \r
185                 return read_buffer;\r
186         }\r
187         \r
188         void draw(const std::vector<render_item>& stream)\r
189         {       \r
190                 if(stream.empty())\r
191                         return;                         \r
192                 \r
193                 BOOST_FOREACH(auto item, stream)\r
194                 {\r
195                         bool local_key = false;\r
196                         bool layer_key = false;\r
197 \r
198                         // Setup key and kernel\r
199                                         \r
200                         if(item.transform.get_is_key()) // This is a key frame, render it to the local_key buffer for later use.\r
201                         {\r
202                                 if(!local_key_) // Initialize local-key if it is not active.\r
203                                 {\r
204                                         local_key_buffer_->clear();\r
205                                         local_key_buffer_->attach();\r
206                                         local_key_ = true;\r
207                                 }\r
208                         }               \r
209                         else // This is a normal frame. Use key buffers if they are active.\r
210                         {               \r
211                                 local_key = local_key_;\r
212                                 layer_key = layer_key_;\r
213 \r
214                                 if(local_key_) // Use local key if we have it.\r
215                                 {\r
216                                         local_key_buffer_->bind(LOCAL_KEY_INDEX);\r
217                                         draw_buffer_->attach(); \r
218                                 }               \r
219 \r
220                                 if(layer_key_) // Use layer key if we have it.\r
221                                         layer_key_buffer_->bind(LAYER_KEY_INDEX);\r
222                         }       \r
223 \r
224                         // Bind textures\r
225 \r
226                         for(size_t n = 0; n < item.textures.size(); ++n)\r
227                                 item.textures[n]->bind(n);              \r
228                         \r
229                         // Draw\r
230 \r
231                         kernel_.draw(channel_.get_format_desc().width, channel_.get_format_desc().height, item.desc, item.transform, local_key, layer_key);     \r
232                 }\r
233 \r
234                 local_key_ = stream.back().transform.get_is_key(); // Keep for next layer if last frame is key\r
235         }\r
236                         \r
237         safe_ptr<write_frame> create_frame(const void* tag, const core::pixel_format_desc& desc)\r
238         {\r
239                 return make_safe<write_frame>(channel_.ogl(), reinterpret_cast<int>(tag), desc);\r
240         }\r
241 };\r
242 \r
243 image_mixer::image_mixer(video_channel_context& video_channel) : impl_(new implementation(video_channel)){}\r
244 void image_mixer::begin(core::basic_frame& frame){impl_->begin(frame);}\r
245 void image_mixer::visit(core::write_frame& frame){impl_->visit(frame);}\r
246 void image_mixer::end(){impl_->end();}\r
247 safe_ptr<host_buffer> image_mixer::render(){return impl_->render();}\r
248 safe_ptr<write_frame> image_mixer::create_frame(const void* tag, const core::pixel_format_desc& desc){return impl_->create_frame(tag, desc);}\r
249 void image_mixer::begin_layer(){impl_->begin_layer();}\r
250 void image_mixer::end_layer(){impl_->end_layer();}\r
251 image_mixer& image_mixer::operator=(image_mixer&& other)\r
252 {\r
253         impl_ = std::move(other.impl_);\r
254         return *this;\r
255 }\r
256 \r
257 }}