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()
  36 {
  37         if(id)
  38                 glDeleteFramebuffers(1, &id);
  39 }
  40
  41 void OpenGLFramebuffer::set_system_format(const FrameFormat &fmt)
  42 {
  43         static_cast<Framebuffer *>(this)->format = fmt;
  44 }
  45
  46 bool OpenGLFramebuffer::is_format_supported(const FrameFormat &fmt)
  47 {
  48         // Pretend everything is supported if we can't check
  49         if(!ARB_internalformat_query || !ARB_internalformat_query2)
  50                 return true;
  51
  52         unsigned target = (fmt.get_samples()>1 ? GL_TEXTURE_2D_MULTISAMPLE : GL_TEXTURE_2D);
  53         for(FrameAttachment a: fmt)
  54         {
  55                 unsigned pf = get_gl_pixelformat(get_attachment_pixelformat(a));
  56                 int supported = 0;
  57                 glGetInternalformativ(target, pf, GL_FRAMEBUFFER_RENDERABLE, 1, &supported);
  58                 if(supported!=GL_FULL_SUPPORT)
  59                         return false;
  60         }
  61
  62         return true;
  63 }
  64
  65 void OpenGLFramebuffer::require_layered()
  66 {
  67         static Require _req(ARB_geometry_shader4);
  68 }
  69
  70 void OpenGLFramebuffer::resize_system(unsigned w, unsigned h)
  71 {
  72         Framebuffer *self = static_cast<Framebuffer *>(this);
  73         self->width = w;
  74         self->height = h;
  75 }
  76
  77 void OpenGLFramebuffer::update(unsigned mask) const
  78 {
  79         const FrameFormat &format = static_cast<const Framebuffer *>(this)->format;
  80         vector<GLenum> color_bufs;
  81         color_bufs.reserve(format.size());
  82         unsigned i = 0;
  83         for(FrameAttachment a: format)
  84         {
  85                 GLenum gl_attach_point = get_gl_attachment(a);
  86                 if(mask&(1<<i))
  87                 {
  88                         const Framebuffer::Attachment &attch = static_cast<const Framebuffer *>(this)->attachments[i];
  89                         if(attch.tex)
  90                         {
  91                                 if(ARB_direct_state_access)
  92                                 {
  93                                         if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE || attch.layer<0)
  94                                                 glNamedFramebufferTexture(id, gl_attach_point, attch.tex->id, attch.level);
  95                                         else
  96                                                 glNamedFramebufferTextureLayer(id, gl_attach_point, attch.tex->id, attch.level, attch.layer);
  97                                 }
  98                                 else if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE)
  99                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level);
 100                                 else if(attch.layer<0)
 101                                         glFramebufferTexture(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level);
 102                                 else if(attch.tex->target==GL_TEXTURE_2D_ARRAY)
 103                                         glFramebufferTextureLayer(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 104                                 else if(attch.tex->target==GL_TEXTURE_3D)
 105                                         glFramebufferTexture3D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level, attch.layer);
 106                                 else if(attch.tex->target==GL_TEXTURE_CUBE_MAP)
 107                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, get_gl_cube_face(static_cast<TextureCubeFace>(attch.layer)), attch.tex->id, attch.level);
 108                         }
 109                         else if(ARB_direct_state_access)
 110                                 glNamedFramebufferTexture(id, gl_attach_point, 0, 0);
 111                         else
 112                                 glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, GL_TEXTURE_2D, 0, 0);
 113                 }
 114
 115                 if(gl_attach_point!=GL_DEPTH_ATTACHMENT && gl_attach_point!=GL_STENCIL_ATTACHMENT)
 116                         color_bufs.push_back(gl_attach_point);
 117
 118                 ++i;
 119         }
 120
 121         if(color_bufs.size()>1)
 122                 static Require _req(ARB_draw_buffers);
 123
 124         GLenum first_buffer = (color_bufs.empty() ? GL_NONE : color_bufs.front());
 125         if(ARB_direct_state_access)
 126         {
 127                 /* ARB_direct_state_access ties the availability of these functions to
 128                 framebuffers themselves, so no further checks are needed. */
 129                 glNamedFramebufferDrawBuffers(id, color_bufs.size(), &color_bufs[0]);
 130                 glNamedFramebufferReadBuffer(id, first_buffer);
 131         }
 132         else
 133         {
 134                 if(ARB_draw_buffers)
 135                         glDrawBuffers(color_bufs.size(), &color_bufs[0]);
 136                 else if(MSP_buffer_control)
 137                         glDrawBuffer(first_buffer);
 138
 139                 if(MSP_buffer_control)
 140                         glReadBuffer(first_buffer);
 141         }
 142
 143         if(ARB_direct_state_access)
 144                 status = glCheckNamedFramebufferStatus(id, GL_FRAMEBUFFER);
 145         else
 146                 status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 147 }
 148
 149 void OpenGLFramebuffer::require_complete() const
 150 {
 151         if(status==GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT)
 152                 throw framebuffer_incomplete("incomplete or unsupported attachment");
 153         if(status==GL_FRAMEBUFFER_UNSUPPORTED)
 154                 throw framebuffer_incomplete("unsupported configuration");
 155         if(status!=GL_FRAMEBUFFER_COMPLETE)
 156                 throw framebuffer_incomplete(Msp::format("incomplete (%#x)", status));
 157 }
 158
 159 void OpenGLFramebuffer::set_debug_name(const string &name)
 160 {
 161 #ifdef DEBUG
 162         if(KHR_debug)
 163                 glObjectLabel(GL_FRAMEBUFFER, id, name.size(), name.c_str());
 164 #else
 165         (void)name;
 166 #endif
 167 }
 168
 169 } // namespace GL
 170 } // namespace Msp