git.sesse.net Git - casparcg/blob - common/gl/pixel_buffer_object.cpp

   1 #include "../StdAfx.h"\r
   2 \r
   3 #include "pixel_buffer_object.h"\r
   4 \r
   5 #include "../../common/exception/exceptions.h"\r
   6 #include "../../common/gl/gl_check.h"\r
   7 #include "../../common/utility/memory.h"\r
   8 \r
   9 namespace caspar { namespace common { namespace gl {\r
  10                                                                                                                                                                                                                                                                                                                         \r
  11 struct pixel_buffer_object::implementation : boost::noncopyable\r
  12 {\r
  13         implementation(size_t width, size_t height) \r
  14                 : width_(width), height_(height), size_(width*height*4), pbo_(0),\r
  15                         texture_(0), writing_(false), reading_(false), mapped_(false){}\r
  16 \r
  17         ~implementation()\r
  18         {\r
  19                 if(pbo_ != 0)\r
  20                         glDeleteBuffers(1, &pbo_);\r
  21         }       \r
  22 \r
  23         void bind_pbo(GLenum mode)\r
  24         {\r
  25                 if(pbo_ == 0)\r
  26                         GL(glGenBuffers(1, &pbo_));\r
  27                 GL(glBindBuffer(mode, pbo_));\r
  28         }\r
  29 \r
  30         void unbind_pbo(GLenum mode)\r
  31         {\r
  32                 GL(glBindBuffer(mode, 0));\r
  33         }\r
  34         \r
  35         void bind_texture()\r
  36         {\r
  37                 if(texture_ == 0)\r
  38                 {\r
  39                         GL(glGenTextures(1, &texture_));\r
  40 \r
  41                         GL(glBindTexture(GL_TEXTURE_2D, texture_));\r
  42 \r
  43                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));\r
  44                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));\r
  45                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));\r
  46                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE));\r
  47 \r
  48                         GL(glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA8, width_, height_, 0, GL_BGRA, \r
  49                                                                 GL_UNSIGNED_BYTE, NULL));\r
  50                 }\r
  51                 GL(glBindTexture(GL_TEXTURE_2D, texture_));\r
  52         }\r
  53 \r
  54         void begin_write()\r
  55         {\r
  56                 bind_pbo(GL_PIXEL_UNPACK_BUFFER);\r
  57                 if(mapped_)\r
  58                         GL(glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER));\r
  59                 mapped_ = false;\r
  60                 bind_texture();\r
  61                 GL(glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width_, height_, GL_BGRA, \r
  62                                                         GL_UNSIGNED_BYTE, NULL));\r
  63                 unbind_pbo(GL_PIXEL_UNPACK_BUFFER);\r
  64                 writing_ = true;\r
  65         }\r
  66 \r
  67         void* end_write()\r
  68         {\r
  69                 if(mapped_)\r
  70                         BOOST_THROW_EXCEPTION(invalid_operation());\r
  71 \r
  72                 bind_pbo(GL_PIXEL_UNPACK_BUFFER);\r
  73                 GL(glBufferData(GL_PIXEL_UNPACK_BUFFER, size_, NULL, GL_STREAM_DRAW));\r
  74                 auto data = static_cast<unsigned char*>(glMapBuffer(GL_PIXEL_UNPACK_BUFFER, GL_WRITE_ONLY));\r
  75                 unbind_pbo(GL_PIXEL_UNPACK_BUFFER);             \r
  76                 if(!data)\r
  77                         BOOST_THROW_EXCEPTION(invalid_operation() \r
  78                                                                         << msg_info("glMapBuffer failed"));\r
  79                 writing_ = false;\r
  80                 mapped_ = true;\r
  81                 return data;\r
  82         }\r
  83         \r
  84         void begin_read()\r
  85         {       \r
  86                 bind_pbo(GL_PIXEL_PACK_BUFFER);\r
  87                 if(mapped_)\r
  88                         GL(glUnmapBuffer(GL_PIXEL_PACK_BUFFER));        \r
  89                 mapped_ = false;\r
  90                 GL(glBufferData(GL_PIXEL_PACK_BUFFER, size_, NULL, GL_STREAM_READ));    \r
  91                 GL(glReadPixels(0, 0, width_, height_, GL_BGRA, GL_UNSIGNED_BYTE, NULL));\r
  92                 unbind_pbo(GL_PIXEL_PACK_BUFFER);\r
  93                 reading_ = true;\r
  94         }\r
  95 \r
  96         void* end_read()\r
  97         {\r
  98                 if(mapped_)\r
  99                         BOOST_THROW_EXCEPTION(invalid_operation());\r
 100 \r
 101                 bind_pbo(GL_PIXEL_PACK_BUFFER);\r
 102                 auto data = static_cast<unsigned char*>(glMapBuffer(GL_PIXEL_PACK_BUFFER, GL_READ_ONLY));   \r
 103                 unbind_pbo(GL_PIXEL_PACK_BUFFER);\r
 104                 if(!data)\r
 105                         BOOST_THROW_EXCEPTION(std::bad_alloc());\r
 106                 reading_ = false;\r
 107                 mapped_ = true;\r
 108                 return data;\r
 109         }\r
 110 \r
 111         \r
 112         GLuint pbo_;\r
 113         GLuint texture_;\r
 114         size_t width_;\r
 115         size_t height_;\r
 116         size_t size_;\r
 117 \r
 118         bool mapped_;\r
 119         bool writing_;\r
 120         bool reading_;\r
 121 };\r
 122 \r
 123 pixel_buffer_object::pixel_buffer_object(){}\r
 124 pixel_buffer_object::pixel_buffer_object(size_t width, size_t height) \r
 125         : impl_(new implementation(width, height)){}\r
 126 void pixel_buffer_object::create(size_t width, size_t height)\r
 127 {\r
 128         impl_.reset(new implementation(width, height));\r
 129 }\r
 130 void pixel_buffer_object::begin_write() { impl_->begin_write();}\r
 131 void* pixel_buffer_object::end_write() {return impl_->end_write();} \r
 132 void pixel_buffer_object::begin_read() { impl_->begin_read();}\r
 133 void* pixel_buffer_object::end_read(){return impl_->end_read();}\r
 134 void pixel_buffer_object::bind_texture() {impl_->bind_texture();}\r
 135 size_t pixel_buffer_object::width() const {return impl_->width_;}\r
 136 size_t pixel_buffer_object::heigth() const {return impl_->height_;}\r
 137 size_t pixel_buffer_object::size() const {return impl_->size_;}\r
 138 bool pixel_buffer_object::is_reading() const { return impl_->reading_;}\r
 139 bool pixel_buffer_object::is_writing() const { return impl_->writing_;}\r
 140 }}}