Revive: Add support for MSAA OpenGL texture swapchains.

LibreVR · Mar 19, 2023 · 4d837b4 · 4d837b4
1 parent f3a2d8b
commit 4d837b4
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Showing 2 changed files with 39 additions and 6 deletions.
diff --git a/Revive/TextureGL.cpp b/Revive/TextureGL.cpp
@@ -7,6 +7,8 @@
 TextureGL::TextureGL()
  : Texture(0)
  , Framebuffer(0)
+ , ResolveTexture(0)
+ , ResolveFramebuffer(0)
  , m_Width(0)
  , m_Height(0)
  , m_InteropTexture(0)
@@ -21,10 +23,18 @@ TextureGL::~TextureGL()
 
 void TextureGL::ToVRTexture(vr::Texture_t& texture)
 {
+ if (ResolveTexture)
+ {
+ glBlitNamedFramebuffer(Framebuffer, ResolveFramebuffer,
+ 0, 0, m_Width, m_Height, 0, 0, m_Width, m_Height,
+ GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT, GL_NEAREST);
+ }
+
  texture.eColorSpace = vr::ColorSpace_Auto; // TODO: Set this from the texture format
  texture.eType = vr::TextureType_OpenGL;
 #pragma warning( disable : 4312 )
- texture.handle = (void*)static_cast<uintptr_t>(m_InteropTexture ? m_InteropTexture : Texture);
+ texture.handle = (void*)static_cast<uintptr_t>(m_InteropTexture ? m_InteropTexture :
+ ResolveTexture ? ResolveTexture : Texture);
 #pragma warning( default : 4312 )
 }
 
@@ -91,13 +101,34 @@ bool TextureGL::Init(ovrTextureType Type, int Width, int Height, int MipLevels,
  m_Width = Width;
  m_Height = Height;
 
- if (BindFlags & ovrTextureBind_DX_RenderTarget)
+ if (SampleCount > 1 || Type == ovrTexture_2D_External)
  {
+ GLenum attachment = format == GL_DEPTH_COMPONENT || format == GL_DEPTH_STENCIL ?
+ GL_DEPTH_ATTACHMENT : GL_COLOR_ATTACHMENT0;
+
  glCreateFramebuffers(1, &Framebuffer);
- glNamedFramebufferTexture(Framebuffer, GL_COLOR_ATTACHMENT0, Texture, 0);
- glNamedFramebufferReadBuffer(Framebuffer, GL_COLOR_ATTACHMENT0);
- glNamedFramebufferDrawBuffer(Framebuffer, GL_COLOR_ATTACHMENT0);
- return glCheckNamedFramebufferStatus(Framebuffer, GL_FRAMEBUFFER) == GL_FRAMEBUFFER_COMPLETE;
+ glNamedFramebufferTexture(Framebuffer, attachment, Texture, 0);
+ glNamedFramebufferReadBuffer(Framebuffer, attachment);
+ glNamedFramebufferDrawBuffer(Framebuffer, attachment);
+ GLenum completeness = glCheckNamedFramebufferStatus(Framebuffer, GL_FRAMEBUFFER);
+ if (completeness != GL_FRAMEBUFFER_COMPLETE)
+ return false;
+
+ if (SampleCount > 1)
+ {
+ // SteamVR doesn't support OpenGL MSAA textures, so we have to resolve it before returning a VR texture
+ glCreateTextures(GL_TEXTURE_2D, 1, &ResolveTexture);
+ glTextureParameteri(ResolveTexture, GL_TEXTURE_BASE_LEVEL, 0);
+ glTextureParameteri(ResolveTexture, GL_TEXTURE_MAX_LEVEL, 0);
+ glTextureStorage2D(ResolveTexture, 1, internalFormat, Width, Height);
+
+ glCreateFramebuffers(1, &ResolveFramebuffer);
+ glNamedFramebufferTexture(ResolveFramebuffer, attachment, ResolveTexture, 0);
+ glNamedFramebufferReadBuffer(ResolveFramebuffer, attachment);
+ glNamedFramebufferDrawBuffer(ResolveFramebuffer, attachment);
+ if (glCheckNamedFramebufferStatus(ResolveFramebuffer, GL_FRAMEBUFFER) != GL_FRAMEBUFFER_COMPLETE)
+ return false;
+ }
  }
 
  return true;

diff --git a/Revive/TextureGL.h b/Revive/TextureGL.h
@@ -18,6 +18,8 @@ class TextureGL :
 
  unsigned int Texture;
  unsigned int Framebuffer;
+ unsigned int ResolveTexture;
+ unsigned int ResolveFramebuffer;
 
 protected:
  static unsigned int TextureFormatToInternalFormat(ovrTextureFormat format);