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 FrameFormat &format = static_cast<const Framebuffer *>(this)->format;
  87         vector<GLenum> color_bufs;
  88         color_bufs.reserve(format.size());
  89         unsigned i = 0;
  90         for(FrameAttachment a: format)
  91         {
  92                 GLenum gl_attach_point = get_gl_attachment(a);
  93                 if(mask&(1<<i))
  94                 {
  95                         const Framebuffer::Attachment &attch = static_cast<const Framebuffer *>(this)->attachments[i];
  96                         if(attch.tex)
  97                         {
  98                                 if(ARB_direct_state_access)
  99                                 {
 100                                         if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE || attch.layer<0)
 101                                                 glNamedFramebufferTexture(id, gl_attach_point, attch.tex->id, attch.level);
 102                                         else
 103                                                 glNamedFramebufferTextureLayer(id, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 104                                 }
 105                                 else if(attch.tex->target==GL_TEXTURE_2D || attch.tex->target==GL_TEXTURE_2D_MULTISAMPLE)
 106                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level);
 107                                 else if(attch.layer<0)
 108                                         glFramebufferTexture(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level);
 109                                 else if(attch.tex->target==GL_TEXTURE_2D_ARRAY)
 110                                         glFramebufferTextureLayer(GL_FRAMEBUFFER, gl_attach_point, attch.tex->id, attch.level, attch.layer);
 111                                 else if(attch.tex->target==GL_TEXTURE_3D)
 112                                         glFramebufferTexture3D(GL_FRAMEBUFFER, gl_attach_point, attch.tex->target, attch.tex->id, attch.level, attch.layer);
 113                                 else if(attch.tex->target==GL_TEXTURE_CUBE_MAP)
 114                                         glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, get_gl_cube_face(static_cast<TextureCubeFace>(attch.layer)), attch.tex->id, attch.level);
 115                         }
 116                         else if(ARB_direct_state_access)
 117                                 glNamedFramebufferTexture(id, gl_attach_point, 0, 0);
 118                         else
 119                                 glFramebufferTexture2D(GL_FRAMEBUFFER, gl_attach_point, GL_TEXTURE_2D, 0, 0);
 120                 }
 121
 122                 if(gl_attach_point!=GL_DEPTH_ATTACHMENT && gl_attach_point!=GL_STENCIL_ATTACHMENT)
 123                         color_bufs.push_back(gl_attach_point);
 124
 125                 ++i;
 126         }
 127
 128         if(color_bufs.size()>1)
 129                 static Require _req(ARB_draw_buffers);
 130
 131         GLenum first_buffer = (color_bufs.empty() ? GL_NONE : color_bufs.front());
 132         if(ARB_direct_state_access)
 133         {
 134                 /* ARB_direct_state_access ties the availability of these functions to
 135                 framebuffers themselves, so no further checks are needed. */
 136                 glNamedFramebufferDrawBuffers(id, color_bufs.size(), &color_bufs[0]);
 137                 glNamedFramebufferReadBuffer(id, first_buffer);
 138         }
 139         else
 140         {
 141                 if(ARB_draw_buffers)
 142                         glDrawBuffers(color_bufs.size(), &color_bufs[0]);
 143                 else if(MSP_buffer_control)
 144                         glDrawBuffer(first_buffer);
 145
 146                 if(MSP_buffer_control)
 147                         glReadBuffer(first_buffer);
 148         }
 149
 150         if(ARB_direct_state_access)
 151                 status = glCheckNamedFramebufferStatus(id, GL_FRAMEBUFFER);
 152         else
 153                 status = glCheckFramebufferStatus(GL_FRAMEBUFFER);
 154 }
 155
 156 void OpenGLFramebuffer::require_complete() const
 157 {
 158         if(status==GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT)
 159                 throw framebuffer_incomplete("incomplete or unsupported attachment");
 160         if(status==GL_FRAMEBUFFER_UNSUPPORTED)
 161                 throw framebuffer_incomplete("unsupported configuration");
 162         if(status!=GL_FRAMEBUFFER_COMPLETE)
 163                 throw framebuffer_incomplete(Msp::format("incomplete (%#x)", status));
 164 }
 165
 166 void OpenGLFramebuffer::set_debug_name(const string &name)
 167 {
 168 #ifdef DEBUG
 169         if(KHR_debug)
 170                 glObjectLabel(GL_FRAMEBUFFER, id, name.size(), name.c_str());
 171 #else
 172         (void)name;
 173 #endif
 174 }
 175
 176 } // namespace GL
 177 } // namespace Msp