source/framebuffer.cpp

   1 /* $Id$
   2
   3 This file is part of libmspgl
   4 Copyright © 2007-2011  Mikko Rasa, Mikkosoft Productions
   5 Distributed under the LGPL
   6 */
   7
   8 #include "extension.h"
   9 #include "ext_framebuffer_blit.h"
  10 #include "ext_framebuffer_object.h"
  11 #include "framebuffer.h"
  12 #include "misc.h"
  13 #include "renderbuffer.h"
  14 #include "texture2d.h"
  15
  16 using namespace std;
  17
  18 namespace Msp {
  19 namespace GL {
  20
  21 Framebuffer::Framebuffer(unsigned i):
  22         id(i),
  23         dirty(0)
  24 {
  25         if(id)
  26                 throw InvalidParameterValue("System framebuffer must have id 0");
  27
  28         int viewport[4];
  29         glGetIntegerv(GL_VIEWPORT, viewport);
  30         width = viewport[2];
  31         height = viewport[3];
  32 }
  33
  34 Framebuffer::Framebuffer():
  35         width(0),
  36         height(0),
  37         dirty(0)
  38 {
  39         static RequireExtension _ext("GL_EXT_framebuffer_object");
  40
  41         glGenFramebuffersEXT(1, &id);
  42 }
  43
  44 Framebuffer::~Framebuffer()
  45 {
  46         if(id)
  47                 glDeleteFramebuffersEXT(1, &id);
  48         if(current()==this)
  49                 unbind();
  50 }
  51
  52 void Framebuffer::update_attachment(unsigned mask) const
  53 {
  54         if(current()==this)
  55         {
  56                 GLenum color_buf = GL_NONE;
  57                 for(unsigned i=0; i<attachments.size(); ++i)
  58                 {
  59                         const Attachment &attch = attachments[i];
  60                         if(mask&(1<<i))
  61                         {
  62                                 if(attch.type==GL_RENDERBUFFER_EXT)
  63                                         glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, attch.attachment, GL_RENDERBUFFER_EXT, attch.rbuf->get_id());
  64                                 else if(attch.type==GL_TEXTURE_2D)
  65                                 {
  66                                         static_cast<Texture2D *>(attch.tex)->allocate(attch.level);
  67                                         glFramebufferTexture2DEXT(GL_FRAMEBUFFER_EXT, attch.attachment, attch.type, attch.tex->get_id(), attch.level);
  68                                 }
  69                                 else
  70                                         glFramebufferRenderbufferEXT(GL_FRAMEBUFFER_EXT, attch.attachment, 0, 0);
  71                         }
  72
  73                         if(attch.attachment>=COLOR_ATTACHMENT0 && attch.attachment<=COLOR_ATTACHMENT3)
  74                                 color_buf = attch.attachment;
  75                 }
  76
  77                 glDrawBuffer(color_buf);
  78         }
  79         else
  80                 dirty |= mask;
  81 }
  82
  83 void Framebuffer::check_size()
  84 {
  85         for(vector<Attachment>::iterator i=attachments.begin(); i!=attachments.end(); ++i)
  86                 if(i->type)
  87                 {
  88                         if(i->type==GL_RENDERBUFFER_EXT)
  89                         {
  90                                 width = i->rbuf->get_width();
  91                                 height = i->rbuf->get_height();
  92                         }
  93                         else if(i->type==GL_TEXTURE_2D)
  94                         {
  95                                 Texture2D *tex = static_cast<Texture2D *>(i->tex);
  96                                 width = tex->get_width();
  97                                 height = tex->get_height();
  98                         }
  99                         if(current()==this)
 100                                 glViewport(0, 0, width, height);
 101                         break;
 102                 }
 103 }
 104
 105 void Framebuffer::attach(FramebufferAttachment attch, Renderbuffer &rbuf)
 106 {
 107         if(!id)
 108                 throw InvalidState("Can't attach to system framebuffer");
 109
 110         unsigned i = get_attachment_index(attch);
 111         attachments[i].set(rbuf);
 112         update_attachment(1<<i);
 113         check_size();
 114 }
 115
 116 void Framebuffer::attach(FramebufferAttachment attch, Texture2D &tex, unsigned level)
 117 {
 118         if(!id)
 119                 throw InvalidState("Can't attach to system framebuffer");
 120
 121         unsigned i = get_attachment_index(attch);
 122         attachments[i].set(tex, level);
 123         update_attachment(1<<i);
 124         check_size();
 125 }
 126
 127 void Framebuffer::detach(FramebufferAttachment attch)
 128 {
 129         if(!id)
 130                 throw InvalidState("Can't detach from system framebuffer");
 131
 132         unsigned i = get_attachment_index(attch);
 133         attachments[i].clear();
 134         update_attachment(1<<i);
 135         check_size();
 136 }
 137
 138 FramebufferStatus Framebuffer::check_status() const
 139 {
 140         Bind _bind(this, true);
 141         return static_cast<FramebufferStatus>(glCheckFramebufferStatusEXT(GL_FRAMEBUFFER_EXT));
 142 }
 143
 144 void Framebuffer::clear(BufferBits bits)
 145 {
 146         Bind _bind(this, true);
 147         glClear(bits);
 148 }
 149
 150 void Framebuffer::blit_from(const Framebuffer &other, int sx0, int sy0, int sx1, int sy1, int dx0, int dy0, int dx1, int dy1, BufferBits bits, bool filter)
 151 {
 152         static RequireExtension _ext("GL_EXT_framebuffer_blit");
 153
 154         const Framebuffer *old = current();
 155         if(set_current(this))
 156         {
 157                 glBindFramebufferEXT(GL_DRAW_FRAMEBUFFER_EXT, id);
 158                 if(dirty)
 159                 {
 160                         update_attachment(dirty);
 161                         dirty = 0;
 162                 }
 163         }
 164         if(old!=&other)
 165                 glBindFramebufferEXT(GL_READ_FRAMEBUFFER_EXT, other.id);
 166
 167         glBlitFramebufferEXT(sx0, sy0, sx1, sy1, dx0, dy0, dx1, dy1, bits, (filter ? GL_LINEAR : GL_NEAREST));
 168
 169         set_current(old);
 170         glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, (old ? old->id : 0));
 171 }
 172
 173 void Framebuffer::blit_from(const Framebuffer &other, int sx, int sy, unsigned wd, unsigned ht, int dx, int dy, BufferBits bits)
 174 {
 175         blit_from(other, sx, sy, sx+wd, sy+ht, dx, dy, dx+wd, dy+ht, bits, false);
 176 }
 177
 178 void Framebuffer::blit_from(const Framebuffer &other, BufferBits bits, bool filter)
 179 {
 180         blit_from(other, 0, 0, other.width, other.height, 0, 0, width, height, bits, filter);
 181 }
 182
 183 void Framebuffer::bind() const
 184 {
 185         if(set_current(this))
 186         {
 187                 glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, id);
 188                 if(dirty)
 189                 {
 190                         update_attachment(dirty);
 191                         dirty = 0;
 192                 }
 193                 if(width && height)
 194                         glViewport(0, 0, width, height);
 195         }
 196 }
 197
 198 const Framebuffer *Framebuffer::current()
 199 {
 200         if(!cur_obj)
 201                 cur_obj = &system();
 202         return cur_obj;
 203 }
 204
 205 void Framebuffer::unbind()
 206 {
 207         system().bind();
 208 }
 209
 210 Framebuffer &Framebuffer::system()
 211 {
 212         static Framebuffer sys_framebuf(0);
 213         return sys_framebuf;
 214 }
 215
 216 unsigned Framebuffer::get_attachment_index(FramebufferAttachment attch)
 217 {
 218         for(unsigned i=0; i<attachments.size(); ++i)
 219                 if(attachments[i].attachment==attch)
 220                         return i;
 221         attachments.push_back(Attachment(attch));
 222         return attachments.size()-1;
 223 }
 224
 225
 226 Framebuffer::Attachment::Attachment(FramebufferAttachment a):
 227         attachment(a),
 228         type(0),
 229         level(0)
 230 { }
 231
 232 void Framebuffer::Attachment::set(Renderbuffer &r)
 233 {
 234         type = GL_RENDERBUFFER_EXT;
 235         rbuf = &r;
 236         level = 0;
 237 }
 238
 239 void Framebuffer::Attachment::set(Texture &t, unsigned l)
 240 {
 241         type = t.get_target();
 242         tex = &t;
 243         level = l;
 244 }
 245
 246 void Framebuffer::Attachment::clear()
 247 {
 248         type = 0;
 249 }
 250
 251 } // namespace GL
 252 } // namespace Msp