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 void OpenGLFramebuffer::set_system_format(const FrameFormat &fmt)
  43 {
  44         static_cast<Framebuffer *>(this)->format = fmt;
  45 }
  46
  47 bool OpenGLFramebuffer::is_format_supported(const FrameFormat &fmt)
  48 {
  49         // Pretend everything is supported if we can't check
  50         if(!ARB_internalformat_query || !ARB_internalformat_query2)
  51                 return true;
  52
  53         unsigned target = (fmt.get_samples()>1 ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D);
  54         for(FrameAttachment a: fmt)
  55         {
  56                 unsigned pf = get_gl_pixelformat(get_attachment_pixelformat(a));
  57                 int supported = 0;
  58                 glGetInternalformativ(target, pf, GL_FRAMEBUFFER_RENDERABLE, 1, &supported);
  59                 if(supported!=GL_FULL_SUPPORT)
  60                         return false;
  61         }
  62
  63         return true;
  64 }
  65
  66 void OpenGLFramebuffer::require_layered()
  67 {
  68         static Require _req(ARB_geometry_shader4);
  69 }
  70
  71 void OpenGLFramebuffer::resize_system(unsigned w, unsigned h)
  72 {
  73         Framebuffer *self = static_cast<Framebuffer *>(this);
  74         self->width = w;
  75         self->height = h;
  76 }
  77
  78 void OpenGLFramebuffer::update(unsigned mask) const
  79 {
  80         const FrameFormat &format = static_cast<const Framebuffer *>(this)->format;
  81         vector<GLenum> color_bufs;
  82         color_bufs.reserve(format.size());
  83         unsigned i = 0;
  84         for(FrameAttachment a: format)
  85         {
  86                 GLenum gl_attach_point = get_gl_attachment(a);
  87                 if(mask&(1<<i))
  88                 {
  89                         const Framebuffer::Attachment &attch = static_cast<const Framebuffer *>(this)->attachments[i];
  90                         if(attch.tex)
  91                         {
  92                                 if(ARB_direct_state_access)
  93                                 {
  94                                         if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE || attch.layer<0)
  95                                                 glNamedFramebufferTexture(id, gl_attach_point, attch.tex->id, attch.level);
  96                                         else
  97                                                 glNamedFramebufferTextureLayer(id, gl_attach_point, attch.tex->id, attch.level, attch.layer);
  98                                 }
  99                                 else if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE)
 100                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level);
 101                                 else if(attch.layer<0)
 102                                         glFramebufferTexture(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level);
 103                                 else if(attch.tex->target==GL_TEXTURE_2D_ARRAY)
 104                                         glFramebufferTextureLayer(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 105                                 else if(attch.tex->target==GL_TEXTURE_3D)
 106                                         glFramebufferTexture3D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level, attch.layer);
 107                                 else if(attch.tex->target==GL_TEXTURE_CUBE_MAP)
 108                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, get_gl_cube_face(static_cast<TextureCubeFace>(attch.layer)), attch.tex->id, attch.level);
 109                         }
 110                         else if(ARB_direct_state_access)
 111                                 glNamedFramebufferTexture(id, gl_attach_point, 0, 0);
 112                         else
 113                                 glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, GL_TEXTURE_2D, 0, 0);
 114                 }
 115
 116                 if(gl_attach_point!=GL_DEPTH_ATTACHMENT && gl_attach_point!=GL_STENCIL_ATTACHMENT)
 117                         color_bufs.push_back(gl_attach_point);
 118
 119                 ++i;
 120         }
 121
 122         if(color_bufs.size()>1)
 123                 static Require _req(ARB_draw_buffers);
 124
 125         GLenum first_buffer = (color_bufs.empty() ? GL_NONE : color_bufs.front());
 126         if(ARB_direct_state_access)
 127         {
 128                 /* ARB_direct_state_access ties the availability of these functions to
 129                 framebuffers themselves, so no further checks are needed. */
 130                 glNamedFramebufferDrawBuffers(id, color_bufs.size(), &color_bufs[0]);
 131                 glNamedFramebufferReadBuffer(id, first_buffer);
 132         }
 133         else
 134         {
 135                 if(ARB_draw_buffers)
 136                         glDrawBuffers(color_bufs.size(), &color_bufs[0]);
 137                 else if(MSP_buffer_control)
 138                         glDrawBuffer(first_buffer);
 139
 140                 if(MSP_buffer_control)
 141                         glReadBuffer(first_buffer);
 142         }
 143
 144         if(ARB_direct_state_access)
 145                 status = glCheckNamedFramebufferStatus(id, GL_FRAMEBUFFER);
 146         else
 147                 status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 148 }
 149
 150 void OpenGLFramebuffer::require_complete() const
 151 {
 152         if(status==GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT)
 153                 throw framebuffer_incomplete("incomplete or unsupported attachment");
 154         if(status==GL_FRAMEBUFFER_UNSUPPORTED)
 155                 throw framebuffer_incomplete("unsupported configuration");
 156         if(status!=GL_FRAMEBUFFER_COMPLETE)
 157                 throw framebuffer_incomplete(Msp::format("incomplete (%#x)", status));
 158 }
 159
 160 void OpenGLFramebuffer::set_debug_name(const string &name)
 161 {
 162 #ifdef DEBUG
 163         if(KHR_debug)
 164                 glObjectLabel(GL_FRAMEBUFFER, id, name.size(), name.c_str());
 165 #else
 166         (void)name;
 167 #endif
 168 }
 169
 170 } // namespace GL
 171 } // namespace Msp