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 Texture;
  16 class Texture2D;
  17 class Texture2DMultisample;
  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.  Textures can be attached to the logical buffers.  At least one image
  67 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                 Texture *tex;
  79                 unsigned level;
  80                 int layer;
  81
  82                 Attachment(FramebufferAttachment);
  83                 void set(Texture &, unsigned, int);
  84                 void clear();
  85         };
  86
  87         unsigned id;
  88         std::vector<Attachment> attachments;
  89         unsigned width;
  90         unsigned height;
  91         mutable FramebufferStatus status;
  92         mutable unsigned dirty;
  93
  94         Framebuffer(unsigned);
  95 public:
  96         Framebuffer();
  97         ~Framebuffer();
  98
  99         unsigned get_width() const { return width; }
 100         unsigned get_height() const { return height; }
 101
 102 private:
 103         void update() const;
 104         void check_size();
 105         unsigned get_attachment_index(FramebufferAttachment);
 106         void set_attachment(FramebufferAttachment, Texture &, unsigned, int);
 107 public:
 108         void attach(FramebufferAttachment attch, Texture2D &tex, unsigned level = 0);
 109         void attach(FramebufferAttachment attch, Texture2DMultisample &tex);
 110         void attach(FramebufferAttachment attch, Texture3D &tex, unsigned layer, unsigned level = 0);
 111         void attach(FramebufferAttachment attch, TextureCube &tex, TextureCubeFace face, unsigned level = 0);
 112         void attach_layered(FramebufferAttachment attch, Texture3D &tex, unsigned level = 0);
 113         void attach_layered(FramebufferAttachment attch, TextureCube &tex, unsigned level = 0);
 114         void detach(FramebufferAttachment attch);
 115
 116         void resize(const WindowView &);
 117
 118         /** Returns FRAMEBUFFER_COMPLETE if the framebuffer is complete and can be
 119         rendered to, or one of the error status codes otherwise. */
 120         FramebufferStatus get_status() const { return status; }
 121
 122         /** Ensures that the framebuffer is complete, throwing an exception if it
 123         isn't. */
 124         void require_complete() const;
 125
 126         void refresh() const { if(dirty) update(); }
 127
 128         unsigned get_id() const { return id; }
 129
 130         void set_debug_name(const std::string &);
 131
 132         static Framebuffer &system();
 133 };
 134
 135 inline BufferBits operator|(BufferBits a, BufferBits b)
 136 { return static_cast<BufferBits>(static_cast<int>(a)|static_cast<int>(b)); }
 137
 138 } // namespace GL
 139 } // namespace Msp
 140
 141 #endif