Exposed RenderingDevice to script API

Also added an easier way to load native GLSL shaders.

Extras:

Had to fix no-cache for subresources in resource loader, it was not properly working, making shaders not properly reload.

Note:

The precommit hooks are broken because they don't seem to support enums from one class being used in another.
Feel free to fix this after merging this PR.

servers/rendering/rendering_device_binds.cpp

@@ -0,0 +1,167 @@
+#include "rendering_device_binds.h"
+
+Error RDShaderFile::parse_versions_from_text(const String &p_text, OpenIncludeFunction p_include_func, void *p_include_func_userdata) {
+
+	Vector<String> lines = p_text.split("\n");
+
+	bool reading_versions = false;
+	bool stage_found[RD::SHADER_STAGE_MAX] = { false, false, false, false, false };
+	RD::ShaderStage stage = RD::SHADER_STAGE_MAX;
+	static const char *stage_str[RD::SHADER_STAGE_MAX] = {
+		"vertex",
+		"fragment",
+		"tesselation_control",
+		"tesselation_evaluation",
+		"compute"
+	};
+	String stage_code[RD::SHADER_STAGE_MAX];
+	int stages_found = 0;
+	Map<StringName, String> version_texts;
+
+	versions.clear();
+	base_error = "";
+
+	for (int lidx = 0; lidx < lines.size(); lidx++) {
+		String line = lines[lidx];
+
+		{
+			String ls = line.strip_edges();
+			if (ls.begins_with("[") && ls.ends_with("]")) {
+				String section = ls.substr(1, ls.length() - 2).strip_edges();
+				if (section == "versions") {
+					if (stages_found) {
+						base_error = "Invalid shader file, [version] must be the first section found.";
+						break;
+					}
+					reading_versions = true;
+				} else {
+					for (int i = 0; i < RD::SHADER_STAGE_MAX; i++) {
+						if (section == stage_str[i]) {
+							if (stage_found[i]) {
+								base_error = "Invalid shader file, stage appears twice: " + section;
+								break;
+							}
+
+							stage_found[i] = true;
+							stages_found++;
+
+							stage = RD::ShaderStage(i);
+							reading_versions = false;
+							break;
+						}
+					}
+
+					if (base_error != String()) {
+						break;
+					}
+				}
+
+				continue;
+			}
+		}
+
+		if (reading_versions) {
+			String l = line.strip_edges();
+			if (l != "") {
+				int eqpos = l.find("=");
+				if (eqpos == -1) {
+					base_error = "Version syntax is version=\"<defines with C escaping>\".";
+					break;
+				}
+				String version = l.get_slice("=", 0).strip_edges();
+				if (!version.is_valid_identifier()) {
+					base_error = "Version names must be valid identifiers, found '" + version + "' instead.";
+					break;
+				}
+				String define = l.get_slice("=", 1).strip_edges();
+				if (!define.begins_with("\"") || !define.ends_with("\"")) {
+					base_error = "Version text must be quoted using \"\", instead found '" + define + "'.";
+					break;
+				}
+				define = "\n" + define.substr(1, define.length() - 2).c_unescape() + "\n"; //add newline before and after jsut in case
+
+				version_texts[version] = define;
+			}
+		} else {
+			if (stage == RD::SHADER_STAGE_MAX && line.strip_edges() != "") {
+				base_error = "Text was found that does not belong to a valid section: " + line;
+				break;
+			}
+
+			if (stage != RD::SHADER_STAGE_MAX) {
+				if (line.strip_edges().begins_with("#include")) {
+					if (p_include_func) {
+						//process include
+						String include = line.replace("#include", "").strip_edges();
+						if (!include.begins_with("\"") || !include.ends_with("\"")) {
+							base_error = "Malformed #include syntax, expected #include \"<path>\", found instad: " + include;
+							break;
+						}
+						include = include.substr(1, include.length() - 2).strip_edges();
+						String include_text = p_include_func(include, p_include_func_userdata);
+						if (include_text != String()) {
+							stage_code[stage] += "\n" + include_text + "\n";
+						} else {
+							base_error = "#include failed for file '" + include + "'";
+						}
+					} else {
+						base_error = "#include used, but no include function provided.";
+					}
+				} else {
+
+					stage_code[stage] += line + "\n";
+				}
+			}
+		}
+	}
+
+	Ref<RDShaderFile> shader_file;
+	shader_file.instance();
+
+	if (base_error == "") {
+
+		if (stage_found[RD::SHADER_STAGE_COMPUTE] && stages_found > 1) {
+			ERR_FAIL_V_MSG(ERR_PARSE_ERROR, "When writing compute shaders, [compute] mustbe the only stage present.");
+		}
+
+		if (version_texts.empty()) {
+			version_texts[""] = ""; //make sure a default version exists
+		}
+
+		bool errors_found = false;
+
+		/* STEP 2, Compile the versions, add to shader file */
+
+		for (Map<StringName, String>::Element *E = version_texts.front(); E; E = E->next()) {
+
+			Ref<RDShaderBytecode> bytecode;
+			bytecode.instance();
+
+			for (int i = 0; i < RD::SHADER_STAGE_MAX; i++) {
+				String code = stage_code[i];
+				if (code == String()) {
+					continue;
+				}
+				code = code.replace("VERSION_DEFINES", E->get());
+				String error;
+				Vector<uint8_t> spirv = RenderingDevice::get_singleton()->shader_compile_from_source(RD::ShaderStage(i), code, RD::SHADER_LANGUAGE_GLSL, &error, false);
+				bytecode->set_stage_bytecode(RD::ShaderStage(i), spirv);
+				if (error != "") {
+					error += String() + "\n\nStage '" + stage_str[i] + "' source code: \n\n";
+					Vector<String> sclines = code.split("\n");
+					for (int j = 0; j < sclines.size(); j++) {
+						error += itos(j + 1) + "\t\t" + sclines[j] + "\n";
+					}
+					errors_found = true;
+				}
+				bytecode->set_stage_compile_error(RD::ShaderStage(i), error);
+			}
+
+			set_bytecode(bytecode, E->key());
+		}
+
+		return errors_found ? ERR_PARSE_ERROR : OK;
+	} else {
+		return ERR_PARSE_ERROR;
+	}
+}