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, GLenum format) \r
  14                 : width_(width), height_(height), pbo_(0), format_(format),\r
  15                         texture_(0), writing_(false), reading_(false), mapped_(false)\r
  16         {\r
  17                 switch(format)\r
  18                 {\r
  19                 case GL_RGBA:\r
  20                 case GL_BGRA:\r
  21                         internal_ = GL_RGBA8;\r
  22                         size_ = width*height*4;\r
  23                         break;\r
  24                 case GL_BGR:\r
  25                         internal_ = GL_RGB8;\r
  26                         size_ = width*height*3;\r
  27                         break;\r
  28                 case GL_LUMINANCE_ALPHA:\r
  29                         internal_ = GL_LUMINANCE_ALPHA;\r
  30                         size_ = width*height*2;\r
  31                         break;\r
  32                 case GL_LUMINANCE:\r
  33                 case GL_ALPHA:\r
  34                         internal_ = GL_LUMINANCE;\r
  35                         size_ = width*height*1;\r
  36                         break;\r
  37                 default:\r
  38                         BOOST_THROW_EXCEPTION(invalid_argument() << msg_info("format"));\r
  39                 }\r
  40         }\r
  41 \r
  42         ~implementation()\r
  43         {\r
  44                 if(pbo_ != 0)\r
  45                         glDeleteBuffers(1, &pbo_);\r
  46         }       \r
  47 \r
  48         void bind_pbo(GLenum mode)\r
  49         {\r
  50                 if(pbo_ == 0)\r
  51                         GL(glGenBuffers(1, &pbo_));\r
  52                 GL(glBindBuffer(mode, pbo_));\r
  53         }\r
  54 \r
  55         void unbind_pbo(GLenum mode)\r
  56         {\r
  57                 GL(glBindBuffer(mode, 0));\r
  58         }\r
  59         \r
  60         void bind_texture()\r
  61         {\r
  62                 if(texture_ == 0)\r
  63                 {\r
  64                         GL(glGenTextures(1, &texture_));\r
  65 \r
  66                         GL(glBindTexture(GL_TEXTURE_2D, texture_));\r
  67 \r
  68                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR));\r
  69                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR));\r
  70                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE));\r
  71                         GL(glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE));\r
  72 \r
  73                         GL(glTexImage2D(GL_TEXTURE_2D, 0, internal_, width_, height_, 0, format_, \r
  74                                                                 GL_UNSIGNED_BYTE, NULL));\r
  75                 }\r
  76                 GL(glBindTexture(GL_TEXTURE_2D, texture_));\r
  77         }\r
  78 \r
  79         void begin_write()\r
  80         {\r
  81                 bind_pbo(GL_PIXEL_UNPACK_BUFFER);\r
  82                 if(mapped_)\r
  83                         GL(glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER));\r
  84                 mapped_ = false;\r
  85                 bind_texture();\r
  86                 GL(glTexSubImage2D(GL_TEXTURE_2D, 0, 0, 0, width_, height_, format_, \r
  87                                                         GL_UNSIGNED_BYTE, NULL));\r
  88                 unbind_pbo(GL_PIXEL_UNPACK_BUFFER);\r
  89                 writing_ = true;\r
  90         }\r
  91 \r
  92         void* end_write()\r
  93         {\r
  94                 if(mapped_)\r
  95                         BOOST_THROW_EXCEPTION(invalid_operation());\r
  96 \r
  97                 bind_pbo(GL_PIXEL_UNPACK_BUFFER);\r
  98                 GL(glBufferData(GL_PIXEL_UNPACK_BUFFER, size_, NULL, GL_STREAM_DRAW));\r
  99                 auto data = static_cast<unsigned char*>(glMapBuffer(GL_PIXEL_UNPACK_BUFFER, GL_WRITE_ONLY));\r
 100                 unbind_pbo(GL_PIXEL_UNPACK_BUFFER);             \r
 101                 if(!data)\r
 102                         BOOST_THROW_EXCEPTION(invalid_operation() \r
 103                                                                         << msg_info("glMapBuffer failed"));\r
 104                 writing_ = false;\r
 105                 mapped_ = true;\r
 106                 return data;\r
 107         }\r
 108         \r
 109         void begin_read()\r
 110         {       \r
 111                 bind_pbo(GL_PIXEL_PACK_BUFFER);\r
 112                 if(mapped_)\r
 113                         GL(glUnmapBuffer(GL_PIXEL_PACK_BUFFER));        \r
 114                 mapped_ = false;\r
 115                 GL(glBufferData(GL_PIXEL_PACK_BUFFER, size_, NULL, GL_STREAM_READ));    \r
 116                 GL(glReadPixels(0, 0, width_, height_, GL_BGRA, GL_UNSIGNED_BYTE, NULL));\r
 117                 unbind_pbo(GL_PIXEL_PACK_BUFFER);\r
 118                 reading_ = true;\r
 119         }\r
 120 \r
 121         void* end_read()\r
 122         {\r
 123                 if(mapped_)\r
 124                         BOOST_THROW_EXCEPTION(invalid_operation());\r
 125 \r
 126                 bind_pbo(GL_PIXEL_PACK_BUFFER);\r
 127                 auto data = static_cast<unsigned char*>(glMapBuffer(GL_PIXEL_PACK_BUFFER, GL_READ_ONLY));   \r
 128                 unbind_pbo(GL_PIXEL_PACK_BUFFER);\r
 129                 if(!data)\r
 130                         BOOST_THROW_EXCEPTION(std::bad_alloc());\r
 131                 reading_ = false;\r
 132                 mapped_ = true;\r
 133                 return data;\r
 134         }\r
 135 \r
 136         \r
 137         GLuint pbo_;\r
 138         GLuint texture_;\r
 139         size_t width_;\r
 140         size_t height_;\r
 141         size_t size_;\r
 142 \r
 143         bool mapped_;\r
 144         bool writing_;\r
 145         bool reading_;\r
 146 \r
 147         GLint internal_;\r
 148         GLenum format_;\r
 149 };\r
 150 \r
 151 pixel_buffer_object::pixel_buffer_object(){}\r
 152 pixel_buffer_object::pixel_buffer_object(size_t width, size_t height, GLenum format) \r
 153         : impl_(new implementation(width, height, format)){}\r
 154 void pixel_buffer_object::create(size_t width, size_t height, GLenum format)\r
 155 {\r
 156         impl_.reset(new implementation(width, height, format));\r
 157 }\r
 158 void pixel_buffer_object::begin_write() { impl_->begin_write();}\r
 159 void* pixel_buffer_object::end_write() {return impl_->end_write();} \r
 160 void pixel_buffer_object::begin_read() { impl_->begin_read();}\r
 161 void* pixel_buffer_object::end_read(){return impl_->end_read();}\r
 162 void pixel_buffer_object::bind_texture() {impl_->bind_texture();}\r
 163 size_t pixel_buffer_object::width() const {return impl_->width_;}\r
 164 size_t pixel_buffer_object::height() const {return impl_->height_;}\r
 165 size_t pixel_buffer_object::size() const {return impl_->size_;}\r
 166 bool pixel_buffer_object::is_reading() const { return impl_->reading_;}\r
 167 bool pixel_buffer_object::is_writing() const { return impl_->writing_;}\r
 168 }}}