[Fix, Test] (MG_Backend/DirectGLES, MG_State, MG_Util): publish the real default framebuffer depth/stencil format, forward the clip distance enables, and stop trusting a stale format probe for non-2D depth attachments

MobileGL/MG_Util/BackendLoaders/OpenGL/Loader.cpp

@@ -925,6 +925,9 @@ namespace MobileGL::MG_Util::BackendLoader {
                 if (std::strcmp(extension, "GL_EXT_multi_draw_arrays") == 0) {
                     hasMultiDrawArraysExtension = true;
                 }
+                if (std::strcmp(extension, "GL_EXT_clip_cull_distance") == 0) {
+                    caps.SupportsClipDistance = true;
+                }
             }
         }
         // The pointer check on top of the extension check makes each flag sufficient on its own
@@ -978,6 +981,7 @@ namespace MobileGL::MG_Util::BackendLoader {
         MGLOG_I("    compute shaders (ES 3.1 core): %s", caps.SupportsComputeShader ? "yes" : "no");
         MGLOG_I("    base instance (EXT_base_instance; emulated by attribute offsets when absent): %s",
                 caps.SupportsBaseInstance ? "yes" : "no");
+        MGLOG_I("    clip distances (EXT_clip_cull_distance): %s", caps.SupportsClipDistance ? "yes" : "no");
 
         MGLOG_I("OpenGL ES capabilities:");
         glesFuncs.glGetIntegerv(GL_UNIFORM_BUFFER_OFFSET_ALIGNMENT, &caps.UniformBufferOffsetAlignment);

MobileGL/MG_Util/BackendLoaders/OpenGL/Loader.h

@@ -1163,6 +1163,13 @@ namespace MobileGL {
             // Compute shaders are usable: ES 3.1 core (there is no pre-3.1 extension in ES), with
             // the dispatch and barrier entry points resolved.
             Bool SupportsComputeShader = false;
+            // GL_EXT_clip_cull_distance is present: the driver accepts gl_ClipDistance in ESSL
+            // (which is what SPIRV-Cross emits, together with a `#extension ... : require`) AND
+            // the GL_CLIP_DISTANCE0_EXT..7_EXT enable tokens, whose values are the desktop ones.
+            // ES core has neither at any version, so without this a gl_ClipDistance shader cannot
+            // compile and the per-distance enables have nowhere to go - clipping silently never
+            // happens, which is exactly what KHR-GLxx.clip_distance.functional catches.
+            Bool SupportsClipDistance = false;
             // GL_RENDERER contains "ANGLE".
             Bool IsAngleRenderer = false;
             // GL_RENDERER contains both "ANGLE" and "llvmpipe".