texture_cache: Implement rendering to 3D textures

This allows rendering to 3D textures with more than one slice.
Applications are allowed to render to more than one slice of a texture
using gl_Layer from a VTG shader.

This also requires reworking how 3D texture collisions are handled, for
now, this commit allows rendering to slices but not to miplevels. When a
render target attempts to write to a mipmap, we fallback to the previous
implementation (copying or flushing as needed).

- Fixes color correction 3D textures on UE4 games (rainbow effects).
- Allows Xenoblade games to render to 3D textures directly.

1 files changed, 13 insertions, 4 deletions

diff --git a/src/video_core/texture_cache/surface_params.cpp b/src/video_core/texture_cache/surface_params.cpp
index 884fabffe..642eeb850 100644
--- a/src/video_core/texture_cache/surface_params.cpp
+++ b/src/video_core/texture_cache/surface_params.cpp
@@ -215,10 +215,19 @@ SurfaceParams SurfaceParams::CreateForFramebuffer(Core::System& system, std::siz
     params.num_levels = 1;
     params.emulated_levels = 1;
 
-    const bool is_layered = config.layers > 1 && params.block_depth == 0;
-    params.is_layered = is_layered;
-    params.depth = is_layered ? config.layers.Value() : 1;
-    params.target = is_layered ? SurfaceTarget::Texture2DArray : SurfaceTarget::Texture2D;
+    if (config.memory_layout.is_3d != 0) {
+        params.depth = config.layers.Value();
+        params.is_layered = false;
+        params.target = SurfaceTarget::Texture3D;
+    } else if (config.layers > 1) {
+        params.depth = config.layers.Value();
+        params.is_layered = true;
+        params.target = SurfaceTarget::Texture2DArray;
+    } else {
+        params.depth = 1;
+        params.is_layered = false;
+        params.target = SurfaceTarget::Texture2D;
+    }
     return params;
 }