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 }
  47
  48 void OpenGLFramebuffer::set_system_format(const FrameFormat &fmt)
  49 {
  50         static_cast<Framebuffer *>(this)->format = fmt;
  51 }
  52
  53 bool OpenGLFramebuffer::is_format_supported(const FrameFormat &fmt)
  54 {
  55         // Pretend everything is supported if we can't check
  56         if(!ARB_internalformat_query || !ARB_internalformat_query2)
  57                 return true;
  58
  59         unsigned target = (fmt.get_samples()>1 ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D);
  60         for(FrameAttachment a: fmt)
  61         {
  62                 unsigned pf = get_gl_pixelformat(get_attachment_pixelformat(a));
  63                 int supported = 0;
  64                 glGetInternalformativ(target, pf, GL_FRAMEBUFFER_RENDERABLE, 1, &supported);
  65                 if(supported!=GL_FULL_SUPPORT)
  66                         return false;
  67         }
  68
  69         return true;
  70 }
  71
  72 void OpenGLFramebuffer::require_layered()
  73 {
  74         static Require _req(ARB_geometry_shader4);
  75 }
  76
  77 void OpenGLFramebuffer::resize_system(unsigned w, unsigned h)
  78 {
  79         Framebuffer &self = *static_cast<Framebuffer *>(this);
  80         self.width = w;
  81         self.height = h;
  82 }
  83
  84 void OpenGLFramebuffer::update(unsigned mask) const
  85 {
  86         const Framebuffer &self = *static_cast<const Framebuffer *>(this);
  87
  88         vector<GLenum> color_bufs;
  89         color_bufs.reserve(self.format.size());
  90         unsigned i = 0;
  91         for(FrameAttachment a: self.format)
  92         {
  93                 GLenum gl_attach_point = get_gl_attachment(a);
  94                 if(mask&(1<<i))
  95                 {
  96                         const Framebuffer::Attachment &attch = self.attachments[i];
  97                         if(attch.tex)
  98                         {
  99                                 if(ARB_direct_state_access)
 100                                 {
 101                                         if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE || attch.layer<0)
 102                                                 glNamedFramebufferTexture(id, gl_attach_point, attch.tex->id, attch.level);
 103                                         else
 104                                                 glNamedFramebufferTextureLayer(id, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 105                                 }
 106                                 else if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE)
 107                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level);
 108                                 else if(attch.layer<0)
 109                                         glFramebufferTexture(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level);
 110                                 else if(attch.tex->target==GL_TEXTURE_2D_ARRAY)
 111                                         glFramebufferTextureLayer(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 112                                 else if(attch.tex->target==GL_TEXTURE_3D)
 113                                         glFramebufferTexture3D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level, attch.layer);
 114                                 else if(attch.tex->target==GL_TEXTURE_CUBE_MAP)
 115                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, get_gl_cube_face(static_cast<TextureCubeFace>(attch.layer)), attch.tex->id, attch.level);
 116                         }
 117                         else if(ARB_direct_state_access)
 118                                 glNamedFramebufferTexture(id, gl_attach_point, 0, 0);
 119                         else
 120                                 glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, GL_TEXTURE_2D, 0, 0);
 121                 }
 122
 123                 if(gl_attach_point!=GL_DEPTH_ATTACHMENT && gl_attach_point!=GL_STENCIL_ATTACHMENT)
 124                         color_bufs.push_back(gl_attach_point);
 125
 126                 ++i;
 127         }
 128
 129         if(color_bufs.size()>1)
 130                 static Require _req(ARB_draw_buffers);
 131
 132         GLenum first_buffer = (color_bufs.empty() ? GL_NONE : color_bufs.front());
 133         if(ARB_direct_state_access)
 134         {
 135                 /* ARB_direct_state_access ties the availability of these functions to
 136                 framebuffers themselves, so no further checks are needed. */
 137                 glNamedFramebufferDrawBuffers(id, color_bufs.size(), &color_bufs[0]);
 138                 glNamedFramebufferReadBuffer(id, first_buffer);
 139         }
 140         else
 141         {
 142                 if(ARB_draw_buffers)
 143                         glDrawBuffers(color_bufs.size(), &color_bufs[0]);
 144                 else if(MSP_buffer_control)
 145                         glDrawBuffer(first_buffer);
 146
 147                 if(MSP_buffer_control)
 148                         glReadBuffer(first_buffer);
 149         }
 150
 151         if(ARB_direct_state_access)
 152                 status = glCheckNamedFramebufferStatus(id, GL_FRAMEBUFFER);
 153         else
 154                 status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 155 }
 156
 157 void OpenGLFramebuffer::require_complete() const
 158 {
 159         if(status==GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT)
 160                 throw framebuffer_incomplete("incomplete or unsupported attachment");
 161         if(status==GL_FRAMEBUFFER_UNSUPPORTED)
 162                 throw framebuffer_incomplete("unsupported configuration");
 163         if(status!=GL_FRAMEBUFFER_COMPLETE)
 164                 throw framebuffer_incomplete(Msp::format("incomplete (%#x)", status));
 165 }
 166
 167 void OpenGLFramebuffer::set_debug_name(const string &name)
 168 {
 169 #ifdef DEBUG
 170         if(KHR_debug)
 171                 glObjectLabel(GL_FRAMEBUFFER, id, name.size(), name.c_str());
 172 #else
 173         (void)name;
 174 #endif
 175 }
 176
 177 } // namespace GL
 178 } // namespace Msp