[vk, opengl] recognize and use ETC2 (if available) textures natively (#3237)

this makes it so VK and OGL backends map the NVIDIA's ETC2 into VK_FORMAT_ETC-whatever and GL_ETC-whatever remaps, instead of using the default fallback for AR8G8B8. in short, just make the ETC2 textures be submitted as ETC2 instead of being submit as A8R8G8B8.

Signed-off-by: lizzie lizzie@eden-emu.dev

Reviewed-on: https://git.eden-emu.dev/eden-emu/eden/pulls/3237
Reviewed-by: Ghost <>
Reviewed-by: crueter <crueter@eden-emu.dev>

1 files changed, 18 insertions, 1 deletions

diff --git a/src/video_core/surface.cpp b/src/video_core/surface.cpp
index 1998849e84..69c1720943 100644
--- a/src/video_core/surface.cpp
+++ b/src/video_core/surface.cpp
@@ -1,4 +1,4 @@
-// SPDX-FileCopyrightText: Copyright 2025 Eden Emulator Project
+// SPDX-FileCopyrightText: Copyright 2026 Eden Emulator Project
 // SPDX-License-Identifier: GPL-3.0-or-later
 
 // SPDX-FileCopyrightText: 2014 Citra Emulator Project
@@ -336,6 +336,20 @@ bool IsPixelFormatBCn(PixelFormat format) {
     }
 }
 
+bool IsPixelFormatETC2(PixelFormat format) {
+    switch (format) {
+    case PixelFormat::ETC2_RGB_UNORM:
+    case PixelFormat::ETC2_RGBA_UNORM:
+    case PixelFormat::ETC2_RGB_PTA_UNORM:
+    case PixelFormat::ETC2_RGB_SRGB:
+    case PixelFormat::ETC2_RGBA_SRGB:
+    case PixelFormat::ETC2_RGB_PTA_SRGB:
+        return true;
+    default:
+        return false;
+    }
+}
+
 bool IsPixelFormatSRGB(PixelFormat format) {
     switch (format) {
     case PixelFormat::A8B8G8R8_SRGB:
@@ -344,6 +358,9 @@ bool IsPixelFormatSRGB(PixelFormat format) {
     case PixelFormat::BC2_SRGB:
     case PixelFormat::BC3_SRGB:
     case PixelFormat::BC7_SRGB:
+    case PixelFormat::ETC2_RGB_SRGB:
+    case PixelFormat::ETC2_RGBA_SRGB:
+    case PixelFormat::ETC2_RGB_PTA_SRGB:
     case PixelFormat::ASTC_2D_4X4_SRGB:
     case PixelFormat::ASTC_2D_8X8_SRGB:
     case PixelFormat::ASTC_2D_8X5_SRGB: