Fix handling of async hidden render mode

- Mute errors when conditioned shader is not ready yet
- Avoid depth pre-pass on meshes that would end up black

drivers/gles3/rasterizer_scene_gles3.cpp

@@ -1136,6 +1136,9 @@ bool RasterizerSceneGLES3::_setup_material(RasterizerStorageGLES3::Material *p_m
 
 	state.scene_shader.set_custom_shader(p_material->shader->custom_code_id);
 	bool rebind = state.scene_shader.bind();
+	if (!ShaderGLES3::get_active()) {
+		return false;
+	}
 
 	if (p_material->ubo_id) {
 		glBindBufferBase(GL_UNIFORM_BUFFER, 1, p_material->ubo_id);
@@ -2173,6 +2176,9 @@ void RasterizerSceneGLES3::_render_list(RenderList::Element **p_elements, int p_
 				storage->info.render.shader_rebind_count++;
 			}
 		}
+		if (!ShaderGLES3::get_active()) {
+			continue;
+		}
 
 		if (!(e->sort_key & SORT_KEY_UNSHADED_FLAG) && !p_directional_add && !p_shadow) {
 			_setup_light(e, p_view_transform);
@@ -2319,6 +2325,11 @@ void RasterizerSceneGLES3::_add_geometry_with_material(RasterizerStorageGLES3::G
 		if (has_blend_alpha || p_material->shader->spatial.uses_depth_texture || ((has_base_alpha || p_instance->cast_shadows == VS::SHADOW_CASTING_SETTING_OFF) && p_material->shader->spatial.depth_draw_mode != RasterizerStorageGLES3::Shader::Spatial::DEPTH_DRAW_ALPHA_PREPASS) || p_material->shader->spatial.depth_draw_mode == RasterizerStorageGLES3::Shader::Spatial::DEPTH_DRAW_NEVER || p_material->shader->spatial.no_depth_test) {
 			return; //bye
 		}
+		if (!p_material->shader->shader->is_custom_code_ready_for_render(p_material->shader->custom_code_id)) {
+			// The shader is not guaranteed to be able to render (i.e., a not yet ready async hidden one);
+			// skip depth rendering because otherwise we risk masking out pixels that won't get written to at the actual render pass
+			return;
+		}
 
 		if (!p_material->shader->spatial.uses_alpha_scissor && !p_material->shader->spatial.writes_modelview_or_projection && !p_material->shader->spatial.uses_vertex && !p_material->shader->spatial.uses_discard && p_material->shader->spatial.depth_draw_mode != RasterizerStorageGLES3::Shader::Spatial::DEPTH_DRAW_ALPHA_PREPASS) {
 			//shader does not use discard and does not write a vertex position, use generic material

drivers/gles3/shader_gles3.cpp

@@ -148,6 +148,34 @@ bool ShaderGLES3::_bind(bool p_binding_fallback) {
 	}
 }
 
+bool ShaderGLES3::is_custom_code_ready_for_render(uint32_t p_code_id) {
+	if (p_code_id == 0) {
+		return true;
+	}
+	if (!is_async_compilation_supported() || get_ubershader_flags_uniform() == -1) {
+		return true;
+	}
+
+	CustomCode *cc = custom_code_map.getptr(p_code_id);
+	ERR_FAIL_COND_V(!cc, false);
+	if (cc->async_mode == ASYNC_MODE_HIDDEN) {
+#ifdef DEBUG_ENABLED
+		if (VS::get_singleton()->is_force_shader_fallbacks_enabled()) {
+			return false;
+		}
+#endif
+		VersionKey effective_version;
+		effective_version.version = new_conditional_version.version;
+		effective_version.code_version = p_code_id;
+		Version *v = version_map.getptr(effective_version);
+		if (!v || cc->version != v->code_version || v->compile_status != Version::COMPILE_STATUS_OK) {
+			return false;
+		}
+	}
+
+	return true;
+}
+
 bool ShaderGLES3::_bind_ubershader() {
 #ifdef DEBUG_ENABLED
 	ERR_FAIL_COND_V(!is_async_compilation_supported(), false);

drivers/gles3/shader_gles3.h

@@ -397,6 +397,7 @@ public:
 	void set_custom_shader_code(uint32_t p_code_id, const String &p_vertex, const String &p_vertex_globals, const String &p_fragment, const String &p_light, const String &p_fragment_globals, const String &p_uniforms, const Vector<StringName> &p_texture_uniforms, const Vector<CharString> &p_custom_defines, AsyncMode p_async_mode);
 	void set_custom_shader(uint32_t p_code_id);
 	void free_custom_shader(uint32_t p_code_id);
+	bool is_custom_code_ready_for_render(uint32_t p_code_id);
 
 	uint32_t get_version() const { return new_conditional_version.version; }
 	bool is_version_ubershader() const { return (new_conditional_version.version & VersionKey::UBERSHADER_FLAG); }