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         status(is_system ? GL_FRAMEBUFFER_COMPLETE : GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT)
  23 {
  24         if(!is_system)
  25         {
  26                 static Require _req(EXT_framebuffer_object);
  27
  28                 if(ARB_direct_state_access)
  29                         glCreateFramebuffers(1, &id);
  30                 else
  31                         glGenFramebuffers(1, &id);
  32         }
  33 }
  34
  35 OpenGLFramebuffer::OpenGLFramebuffer(OpenGLFramebuffer &&other):
  36         id(other.id),
  37         status(other.status)
  38 {
  39         other.id = 0;
  40 }
  41
  42 OpenGLFramebuffer::~OpenGLFramebuffer()
  43 {
  44         if(id)
  45                 glDeleteFramebuffers(1, &id);
  46         if(resolve_id)
  47                 glDeleteFramebuffers(1, &resolve_id);
  48 }
  49
  50 void OpenGLFramebuffer::set_system_format(const FrameFormat &fmt)
  51 {
  52         static_cast<Framebuffer *>(this)->format = fmt;
  53 }
  54
  55 bool OpenGLFramebuffer::is_format_supported(const FrameFormat &fmt)
  56 {
  57         // Pretend everything is supported if we can't check
  58         if(!ARB_internalformat_query || !ARB_internalformat_query2)
  59                 return true;
  60
  61         unsigned target = (fmt.get_samples()>1 ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D);
  62         for(FrameAttachment a: fmt)
  63         {
  64                 unsigned pf = get_gl_pixelformat(get_attachment_pixelformat(a));
  65                 int supported = 0;
  66                 glGetInternalformativ(target, pf, GL_FRAMEBUFFER_RENDERABLE, 1, &supported);
  67                 if(supported!=GL_FULL_SUPPORT)
  68                         return false;
  69         }
  70
  71         return true;
  72 }
  73
  74 void OpenGLFramebuffer::format_changed(const FrameFormat &format)
  75 {
  76         if(format.get_samples()>1 && !resolve_id)
  77         {
  78                 if(ARB_direct_state_access)
  79                         glCreateFramebuffers(1, &resolve_id);
  80                 else
  81                         glGenFramebuffers(1, &resolve_id);
  82         }
  83 }
  84
  85 void OpenGLFramebuffer::require_layered()
  86 {
  87         static Require _req(ARB_geometry_shader4);
  88 }
  89
  90 void OpenGLFramebuffer::resize_system(unsigned w, unsigned h)
  91 {
  92         Framebuffer &self = *static_cast<Framebuffer *>(this);
  93         self.width = w;
  94         self.height = h;
  95 }
  96
  97 void OpenGLFramebuffer::update(unsigned mask) const
  98 {
  99         const Framebuffer &self = *static_cast<const Framebuffer *>(this);
 100
 101         update(mask, false);
 102         if(self.has_resolve_attachments())
 103         {
 104                 if(!ARB_direct_state_access)
 105                         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, resolve_id);
 106
 107                 update(mask, true);
 108
 109                 if(!ARB_direct_state_access)
 110                         glBindFramebuffer(GL_DRAW_FRAMEBUFFER, id);
 111         }
 112 }
 113
 114 void OpenGLFramebuffer::update(unsigned mask, bool resolve) const
 115 {
 116         const Framebuffer &self = *static_cast<const Framebuffer *>(this);
 117         unsigned obj_id = (resolve ? resolve_id : id);
 118         Texture *Framebuffer::Attachment::*member = (resolve ? &Framebuffer::Attachment::resolve : &Framebuffer::Attachment::tex);
 119
 120         vector<GLenum> color_bufs;
 121         color_bufs.reserve(self.format.size());
 122         unsigned i = 0;
 123         for(FrameAttachment a: self.format)
 124         {
 125                 GLenum gl_attach_point = get_gl_attachment(a);
 126                 if(mask&(1<<i))
 127                 {
 128                         const Framebuffer::Attachment &attch = self.attachments[i];
 129                         Texture *tex = attch.*member;
 130                         if(tex)
 131                         {
 132                                 if(ARB_direct_state_access)
 133                                 {
 134                                         if(tex->target==GL_TEXTURE_2D || tex->target==GL_TEXTURE_2D_MULTISAMPLE || attch.layer<0)
 135                                                 glNamedFramebufferTexture(obj_id, gl_attach_point, tex->id, attch.level);
 136                                         else
 137                                                 glNamedFramebufferTextureLayer(obj_id, gl_attach_point, tex->id, attch.level, attch.layer);
 138                                 }
 139                                 else if(tex->target==GL_TEXTURE_2D || tex->target==GL_TEXTURE_2D_MULTISAMPLE)
 140                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, tex->target, tex->id, attch.level);
 141                                 else if(attch.layer<0)
 142                                         glFramebufferTexture(GL_FRAMEBUFFER, gl_attach_point, tex->id, attch.level);
 143                                 else if(tex->target==GL_TEXTURE_2D_ARRAY)
 144                                         glFramebufferTextureLayer(GL_FRAMEBUFFER, gl_attach_point, tex->id, attch.level, attch.layer);
 145                                 else if(tex->target==GL_TEXTURE_3D)
 146                                         glFramebufferTexture3D(GL_FRAMEBUFFER, gl_attach_point, tex->target, tex->id, attch.level, attch.layer);
 147                                 else if(tex->target==GL_TEXTURE_CUBE_MAP)
 148                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, get_gl_cube_face(static_cast<TextureCubeFace>(attch.layer)), tex->id, attch.level);
 149                         }
 150                         else if(ARB_direct_state_access)
 151                                 glNamedFramebufferTexture(obj_id, gl_attach_point, 0, 0);
 152                         else
 153                                 glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, GL_TEXTURE_2D, 0, 0);
 154                 }
 155
 156                 if(gl_attach_point!=GL_DEPTH_ATTACHMENT && gl_attach_point!=GL_STENCIL_ATTACHMENT)
 157                         color_bufs.push_back(gl_attach_point);
 158
 159                 ++i;
 160         }
 161
 162         if(color_bufs.size()>1)
 163                 static Require _req(ARB_draw_buffers);
 164
 165         GLenum first_buffer = (color_bufs.empty() ? GL_NONE : color_bufs.front());
 166         if(ARB_direct_state_access)
 167         {
 168                 /* ARB_direct_state_access ties the availability of these functions to
 169                 framebuffers themselves, so no further checks are needed. */
 170                 glNamedFramebufferDrawBuffers(obj_id, color_bufs.size(), &color_bufs[0]);
 171                 glNamedFramebufferReadBuffer(obj_id, first_buffer);
 172         }
 173         else
 174         {
 175                 if(ARB_draw_buffers)
 176                         glDrawBuffers(color_bufs.size(), &color_bufs[0]);
 177                 else if(MSP_buffer_control)
 178                         glDrawBuffer(first_buffer);
 179
 180                 if(MSP_buffer_control)
 181                         glReadBuffer(first_buffer);
 182         }
 183
 184         if(!resolve)
 185         {
 186                 if(ARB_direct_state_access)
 187                         status = glCheckNamedFramebufferStatus(obj_id, GL_FRAMEBUFFER);
 188                 else
 189                         status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 190         }
 191 }
 192
 193 void OpenGLFramebuffer::require_complete() const
 194 {
 195         if(status==GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT)
 196                 throw framebuffer_incomplete("incomplete or unsupported attachment");
 197         if(status==GL_FRAMEBUFFER_UNSUPPORTED)
 198                 throw framebuffer_incomplete("unsupported configuration");
 199         if(status!=GL_FRAMEBUFFER_COMPLETE)
 200                 throw framebuffer_incomplete(Msp::format("incomplete (%#x)", status));
 201 }
 202
 203 void OpenGLFramebuffer::set_debug_name(const string &name)
 204 {
 205 #ifdef DEBUG
 206         if(KHR_debug)
 207         {
 208                 glObjectLabel(GL_FRAMEBUFFER, id, name.size(), name.c_str());
 209                 if(resolve_id)
 210                 {
 211                         string resolve_name = name+" [resolve]";
 212                         glObjectLabel(GL_FRAMEBUFFER, resolve_id, resolve_name.size(), resolve_name.c_str());
 213                 }
 214         }
 215 #else
 216         (void)name;
 217 #endif
 218 }
 219
 220 } // namespace GL
 221 } // namespace Msp