source/backends/opengl/framebuffer_backend.cpp

   1 #include <msp/gl/extensions/arb_draw_buffers.h>
   2 #include <msp/gl/extensions/arb_direct_state_access.h>
   3 #include <msp/gl/extensions/arb_geometry_shader4.h>
   4 #include <msp/gl/extensions/arb_internalformat_query.h>
   5 #include <msp/gl/extensions/arb_internalformat_query2.h>
   6 #include <msp/gl/extensions/ext_framebuffer_object.h>
   7 #include <msp/gl/extensions/ext_texture_array.h>
   8 #include <msp/gl/extensions/ext_texture3d.h>
   9 #include <msp/gl/extensions/msp_buffer_control.h>
  10 #include <msp/gl/extensions/khr_debug.h>
  11 #include <msp/strings/format.h>
  12 #include "framebuffer.h"
  13 #include "framebuffer_backend.h"
  14 #include "gl.h"
  15
  16 using namespace std;
  17
  18 namespace Msp {
  19 namespace GL {
  20
  21 OpenGLFramebuffer::OpenGLFramebuffer(bool is_system):
  22         id(0),
  23         status(is_system ? GL_FRAMEBUFFER_COMPLETE : GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT)
  24 {
  25         if(!is_system)
  26         {
  27                 static Require _req(EXT_framebuffer_object);
  28
  29                 if(ARB_direct_state_access)
  30                         glCreateFramebuffers(1, &id);
  31                 else
  32                         glGenFramebuffers(1, &id);
  33         }
  34 }
  35
  36 OpenGLFramebuffer::~OpenGLFramebuffer()
  37 {
  38         if(id)
  39                 glDeleteFramebuffers(1, &id);
  40 }
  41
  42 FrameFormat OpenGLFramebuffer::get_system_format()
  43 {
  44         FrameFormat format;
  45
  46         if(EXT_framebuffer_object)
  47         {
  48                 int value;
  49                 glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER, GL_BACK, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &value);
  50                 if(value==GL_NONE)
  51                         glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER, GL_FRONT, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &value);
  52                 if(value!=GL_NONE)
  53                         format = (format,COLOR_ATTACHMENT);
  54
  55                 glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER, GL_DEPTH, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &value);
  56                 if(value!=GL_NONE)
  57                         format = (format,DEPTH_ATTACHMENT);
  58
  59                 glGetFramebufferAttachmentParameteriv(GL_FRAMEBUFFER, GL_STENCIL, GL_FRAMEBUFFER_ATTACHMENT_OBJECT_TYPE, &value);
  60                 if(value!=GL_NONE)
  61                         format = (format,STENCIL_ATTACHMENT);
  62         }
  63
  64         return format;
  65 }
  66
  67 void OpenGLFramebuffer::get_system_size(unsigned &width, unsigned &height)
  68 {
  69         int view[4];
  70         glGetIntegerv(GL_VIEWPORT, view);
  71         width = view[2];
  72         height = view[3];
  73 }
  74
  75 bool OpenGLFramebuffer::is_format_supported(const FrameFormat &fmt)
  76 {
  77         // Pretend everything is supported if we can't check
  78         if(!ARB_internalformat_query || !ARB_internalformat_query2)
  79                 return true;
  80
  81         unsigned target = (fmt.get_samples()>1 ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D);
  82         for(FrameAttachment a: fmt)
  83         {
  84                 unsigned pf = get_gl_pixelformat(get_attachment_pixelformat(a));
  85                 int supported = 0;
  86                 glGetInternalformativ(target, pf, GL_FRAMEBUFFER_RENDERABLE, 1, &supported);
  87                 if(supported!=GL_FULL_SUPPORT)
  88                         return false;
  89         }
  90
  91         return true;
  92 }
  93
  94 void OpenGLFramebuffer::require_layered()
  95 {
  96         static Require _req(ARB_geometry_shader4);
  97 }
  98
  99 void OpenGLFramebuffer::update(unsigned mask) const
 100 {
 101         const FrameFormat &format = static_cast<const Framebuffer *>(this)->format;
 102         vector<GLenum> color_bufs;
 103         color_bufs.reserve(format.size());
 104         unsigned i = 0;
 105         for(FrameAttachment a: format)
 106         {
 107                 GLenum gl_attach_point = get_gl_attachment(a);
 108                 if(mask&(1<<i))
 109                 {
 110                         const Framebuffer::Attachment &attch = static_cast<const Framebuffer *>(this)->attachments[i];
 111                         if(attch.tex)
 112                         {
 113                                 if(ARB_direct_state_access)
 114                                 {
 115                                         if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE || attch.layer<0)
 116                                                 glNamedFramebufferTexture(id, gl_attach_point, attch.tex->id, attch.level);
 117                                         else
 118                                                 glNamedFramebufferTextureLayer(id, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 119                                 }
 120                                 else if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE)
 121                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level);
 122                                 else if(attch.layer<0)
 123                                         glFramebufferTexture(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level);
 124                                 else if(attch.tex->target==GL_TEXTURE_2D_ARRAY)
 125                                         glFramebufferTextureLayer(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 126                                 else if(attch.tex->target==GL_TEXTURE_3D)
 127                                         glFramebufferTexture3D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level, attch.layer);
 128                                 else if(attch.tex->target==GL_TEXTURE_CUBE_MAP)
 129                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, get_gl_cube_face(static_cast<TextureCubeFace>(attch.layer)), attch.tex->id, attch.level);
 130                         }
 131                         else if(ARB_direct_state_access)
 132                                 glNamedFramebufferTexture(id, gl_attach_point, 0, 0);
 133                         else
 134                                 glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, GL_TEXTURE_2D, 0, 0);
 135                 }
 136
 137                 if(gl_attach_point!=GL_DEPTH_ATTACHMENT && gl_attach_point!=GL_STENCIL_ATTACHMENT)
 138                         color_bufs.push_back(gl_attach_point);
 139
 140                 ++i;
 141         }
 142
 143         if(color_bufs.size()>1)
 144                 static Require _req(ARB_draw_buffers);
 145
 146         GLenum first_buffer = (color_bufs.empty() ? GL_NONE : color_bufs.front());
 147         if(ARB_direct_state_access)
 148         {
 149                 /* ARB_direct_state_access ties the availability of these functions to
 150                 framebuffers themselves, so no further checks are needed. */
 151                 glNamedFramebufferDrawBuffers(id, color_bufs.size(), &color_bufs[0]);
 152                 glNamedFramebufferReadBuffer(id, first_buffer);
 153         }
 154         else
 155         {
 156                 if(ARB_draw_buffers)
 157                         glDrawBuffers(color_bufs.size(), &color_bufs[0]);
 158                 else if(MSP_buffer_control)
 159                         glDrawBuffer(first_buffer);
 160
 161                 if(MSP_buffer_control)
 162                         glReadBuffer(first_buffer);
 163         }
 164
 165         if(ARB_direct_state_access)
 166                 status = glCheckNamedFramebufferStatus(id, GL_FRAMEBUFFER);
 167         else
 168                 status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 169 }
 170
 171 void OpenGLFramebuffer::require_complete() const
 172 {
 173         if(status==GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT)
 174                 throw framebuffer_incomplete("incomplete or unsupported attachment");
 175         if(status==GL_FRAMEBUFFER_UNSUPPORTED)
 176                 throw framebuffer_incomplete("unsupported configuration");
 177         if(status!=GL_FRAMEBUFFER_COMPLETE)
 178                 throw framebuffer_incomplete(Msp::format("incomplete (%#x)", status));
 179 }
 180
 181 void OpenGLFramebuffer::set_debug_name(const string &name)
 182 {
 183 #ifdef DEBUG
 184         if(KHR_debug)
 185                 glObjectLabel(GL_FRAMEBUFFER, id, name.size(), name.c_str());
 186 #else
 187         (void)name;
 188 #endif
 189 }
 190
 191 } // namespace GL
 192 } // namespace Msp