From d583fc1e97a78dc6a893c332b3537218ddae194a Mon Sep 17 00:00:00 2001
From: Fernando Sahmkow <fsahmkow27@gmail.com>
Date: Fri, 8 Feb 2019 19:31:35 -0400
Subject: [PATCH] rasterizer_cache_gl: Notify on framebuffer change

---
 .../renderer_opengl/gl_rasterizer_cache.cpp   | 20 ++++++++++++++++---
 .../renderer_opengl/gl_rasterizer_cache.h     |  7 ++++++-
 2 files changed, 23 insertions(+), 4 deletions(-)

diff --git a/src/video_core/renderer_opengl/gl_rasterizer_cache.cpp b/src/video_core/renderer_opengl/gl_rasterizer_cache.cpp
index 81b6099f9..2d2bbd6ac 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer_cache.cpp
+++ b/src/video_core/renderer_opengl/gl_rasterizer_cache.cpp
@@ -968,18 +968,27 @@ Surface RasterizerCacheOpenGL::GetColorBufferSurface(std::size_t index, bool pre
     gpu.dirty_flags.color_buffer.reset(index);
 
     ASSERT(index < Tegra::Engines::Maxwell3D::Regs::NumRenderTargets);
+    auto Notify = [&]() {
+        if (last_color_buffers[index] != current_color_buffers[index]) {
+            NotifyFrameBufferChange(current_color_buffers[index]);
+        }
+        last_color_buffers[index] = current_color_buffers[index];
+    };
 
     if (index >= regs.rt_control.count) {
-        return last_color_buffers[index] = {};
+        Notify();
+        return current_color_buffers[index] = {};
     }
 
     if (regs.rt[index].Address() == 0 || regs.rt[index].format == Tegra::RenderTargetFormat::NONE) {
-        return last_color_buffers[index] = {};
+        Notify();
+        return current_color_buffers[index] = {};
     }
 
     const SurfaceParams color_params{SurfaceParams::CreateForFramebuffer(index)};
 
-    return last_color_buffers[index] = GetSurface(color_params, preserve_contents);
+    Notify();
+    return current_color_buffers[index] = GetSurface(color_params, preserve_contents);
 }
 
 void RasterizerCacheOpenGL::LoadSurface(const Surface& surface) {
@@ -1290,4 +1299,9 @@ Surface RasterizerCacheOpenGL::TryGetReservedSurface(const SurfaceParams& params
     return {};
 }
 
+void RasterizerCacheOpenGL::NotifyFrameBufferChange(Surface triggering_surface) {
+    if (triggering_surface == nullptr)
+        return;
+}
+
 } // namespace OpenGL
diff --git a/src/video_core/renderer_opengl/gl_rasterizer_cache.h b/src/video_core/renderer_opengl/gl_rasterizer_cache.h
index 838554c35..cc27fefb5 100644
--- a/src/video_core/renderer_opengl/gl_rasterizer_cache.h
+++ b/src/video_core/renderer_opengl/gl_rasterizer_cache.h
@@ -34,6 +34,7 @@ using SurfaceTarget = VideoCore::Surface::SurfaceTarget;
 using SurfaceType = VideoCore::Surface::SurfaceType;
 using PixelFormat = VideoCore::Surface::PixelFormat;
 using ComponentType = VideoCore::Surface::ComponentType;
+using Maxwell = Tegra::Engines::Maxwell3D::Regs;
 
 struct SurfaceParams {
     enum class SurfaceClass {
@@ -449,6 +450,9 @@ private:
     /// Tries to get a reserved surface for the specified parameters
     Surface TryGetReservedSurface(const SurfaceParams& params);
 
+    /// When a render target is changed, this method is called with the previous render target
+    void NotifyFrameBufferChange(Surface triggering_surface);
+
     /// Performs a slow but accurate surface copy, flushing to RAM and reinterpreting the data
     void AccurateCopySurface(const Surface& src_surface, const Surface& dst_surface);
     void FastLayeredCopySurface(const Surface& src_surface, const Surface& dst_surface);
@@ -469,7 +473,8 @@ private:
     /// using the new format.
     OGLBuffer copy_pbo;
 
-    std::array<Surface, Tegra::Engines::Maxwell3D::Regs::NumRenderTargets> last_color_buffers;
+    std::array<Surface, Maxwell::NumRenderTargets> last_color_buffers;
+    std::array<Surface, Maxwell::NumRenderTargets> current_color_buffers;
     Surface last_depth_buffer;
 };