source/core/framebuffer.h

   1 #ifndef MSP_GL_FRAMEBUFFER_H_
   2 #define MSP_GL_FRAMEBUFFER_H_
   3
   4 #include <vector>
   5 #include "gl.h"
   6 #include "texturecube.h"
   7 #include <msp/gl/extensions/arb_geometry_shader4.h>
   8 #include <msp/gl/extensions/ext_framebuffer_multisample.h>
   9 #include <msp/gl/extensions/ext_framebuffer_object.h>
  10 #include <msp/gl/extensions/nv_fbo_color_attachments.h>
  11
  12 namespace Msp {
  13 namespace GL {
  14
  15 class Renderbuffer;
  16 class Texture;
  17 class Texture2D;
  18 class Texture3D;
  19 class WindowView;
  20
  21 enum FramebufferAttachment
  22 {
  23         COLOR_ATTACHMENT0  = GL_COLOR_ATTACHMENT0,
  24         COLOR_ATTACHMENT1  = GL_COLOR_ATTACHMENT1,
  25         COLOR_ATTACHMENT2  = GL_COLOR_ATTACHMENT2,
  26         COLOR_ATTACHMENT3  = GL_COLOR_ATTACHMENT3,
  27         DEPTH_ATTACHMENT   = GL_DEPTH_ATTACHMENT,
  28         STENCIL_ATTACHMENT = GL_STENCIL_ATTACHMENT
  29 };
  30
  31 enum FramebufferStatus
  32 {
  33         FRAMEBUFFER_INCOMPLETE_ATTACHMENT         = GL_FRAMEBUFFER_INCOMPLETE_ATTACHMENT,
  34         FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT = GL_FRAMEBUFFER_INCOMPLETE_MISSING_ATTACHMENT,
  35         FRAMEBUFFER_INCOMPLETE_DIMENSIONS         = GL_FRAMEBUFFER_INCOMPLETE_DIMENSIONS_EXT,
  36         FRAMEBUFFER_INCOMPLETE_FORMATS            = GL_FRAMEBUFFER_INCOMPLETE_FORMATS_EXT,
  37         FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER        = GL_FRAMEBUFFER_INCOMPLETE_DRAW_BUFFER,
  38         FRAMEBUFFER_INCOMPLETE_READ_BUFFER        = GL_FRAMEBUFFER_INCOMPLETE_READ_BUFFER,
  39         FRAMEBUFFER_INCOMPLETE_MULTISAMPLE        = GL_FRAMEBUFFER_INCOMPLETE_MULTISAMPLE,
  40         FRAMEBUFFER_INCOMPLETE_LAYER_COUNT        = GL_FRAMEBUFFER_INCOMPLETE_LAYER_COUNT_ARB,
  41         FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS      = GL_FRAMEBUFFER_INCOMPLETE_LAYER_TARGETS,
  42         FRAMEBUFFER_UNSUPPORTED                   = GL_FRAMEBUFFER_UNSUPPORTED,
  43         FRAMEBUFFER_COMPLETE                      = GL_FRAMEBUFFER_COMPLETE
  44 };
  45
  46 enum BufferBits
  47 {
  48         COLOR_BUFFER_BIT   = GL_COLOR_BUFFER_BIT,
  49         DEPTH_BUFFER_BIT   = GL_DEPTH_BUFFER_BIT,
  50         STENCIL_BUFFER_BIT = GL_STENCIL_BUFFER_BIT
  51 };
  52
  53 class framebuffer_incomplete: public std::runtime_error
  54 {
  55 public:
  56         framebuffer_incomplete(FramebufferStatus);
  57         virtual ~framebuffer_incomplete() throw() { }
  58 };
  59
  60 /**
  61 Framebuffer objects can be used to perform offscreen rendering.  The most
  62 common application is rendering to a texture, which can then be used for
  63 fullscreen shader effects.
  64
  65 A framebuffer consist of a number of logical buffers, such as color and depth
  66 buffers.  Renderbuffers and Textures can be attached to the logical buffers.  At
  67 least one image must be attached for the framebuffer to be usable.
  68
  69 Requires the GL_EXT_framebuffer_object extension.  The blit functions require
  70 the GL_EXT_framebuffer_blit extension.
  71 */
  72 class Framebuffer
  73 {
  74 private:
  75         struct Attachment
  76         {
  77                 FramebufferAttachment attachment;
  78                 GLenum type;
  79                 union
  80                 {
  81                         Renderbuffer *rbuf;
  82                         Texture *tex;
  83                 };
  84                 unsigned level;
  85                 int layer;
  86
  87                 Attachment(FramebufferAttachment);
  88                 void set(Renderbuffer &);
  89                 void set(Texture &, unsigned, int);
  90                 void clear();
  91         };
  92
  93         unsigned id;
  94         std::vector<Attachment> attachments;
  95         unsigned width;
  96         unsigned height;
  97         mutable FramebufferStatus status;
  98         mutable unsigned dirty;
  99
 100         Framebuffer(unsigned);
 101 public:
 102         Framebuffer();
 103         ~Framebuffer();
 104
 105         unsigned get_width() const { return width; }
 106         unsigned get_height() const { return height; }
 107
 108 private:
 109         void update() const;
 110         void check_size();
 111         unsigned get_attachment_index(FramebufferAttachment);
 112         void set_texture_attachment(FramebufferAttachment, Texture &, unsigned, int);
 113 public:
 114         void attach(FramebufferAttachment attch, Renderbuffer &rbuf);
 115         void attach(FramebufferAttachment attch, Texture2D &tex, unsigned level = 0);
 116         void attach(FramebufferAttachment attch, Texture3D &tex, unsigned layer, unsigned level = 0);
 117         void attach(FramebufferAttachment attch, TextureCube &tex, TextureCubeFace face, unsigned level = 0);
 118         void attach_layered(FramebufferAttachment attch, Texture3D &tex, unsigned level = 0);
 119         void attach_layered(FramebufferAttachment attch, TextureCube &tex, unsigned level = 0);
 120         void detach(FramebufferAttachment attch);
 121
 122         void resize(const WindowView &);
 123
 124         /** Returns FRAMEBUFFER_COMPLETE if the framebuffer is complete and can be
 125         rendered to, or one of the error status codes otherwise. */
 126         FramebufferStatus get_status() const { return status; }
 127
 128         /** Ensures that the framebuffer is complete, throwing an exception if it
 129         isn't. */
 130         void require_complete() const;
 131
 132         void refresh() const { if(dirty) update(); }
 133
 134         unsigned get_id() const { return id; }
 135
 136         void set_debug_name(const std::string &);
 137
 138         static Framebuffer &system();
 139 };
 140
 141 inline BufferBits operator|(BufferBits a, BufferBits b)
 142 { return static_cast<BufferBits>(static_cast<int>(a)|static_cast<int>(b)); }
 143
 144 } // namespace GL
 145 } // namespace Msp
 146
 147 #endif