godot/servers/rendering/shader_preprocessor.h

235 lines
8.1 KiB
C++

/**************************************************************************/
/* shader_preprocessor.h */
/**************************************************************************/
/* This file is part of: */
/* GODOT ENGINE */
/* https://godotengine.org */
/**************************************************************************/
/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur. */
/* */
/* Permission is hereby granted, free of charge, to any person obtaining */
/* a copy of this software and associated documentation files (the */
/* "Software"), to deal in the Software without restriction, including */
/* without limitation the rights to use, copy, modify, merge, publish, */
/* distribute, sublicense, and/or sell copies of the Software, and to */
/* permit persons to whom the Software is furnished to do so, subject to */
/* the following conditions: */
/* */
/* The above copyright notice and this permission notice shall be */
/* included in all copies or substantial portions of the Software. */
/* */
/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, */
/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF */
/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY */
/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, */
/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE */
/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. */
/**************************************************************************/
#ifndef SHADER_PREPROCESSOR_H
#define SHADER_PREPROCESSOR_H
#include "core/string/ustring.h"
#include "core/templates/list.h"
#include "core/templates/local_vector.h"
#include "core/templates/rb_map.h"
#include "core/templates/rb_set.h"
#include "core/typedefs.h"
#include "core/io/resource_loader.h"
#include "core/object/script_language.h"
#include "core/os/os.h"
#include "scene/resources/shader.h"
#include "scene/resources/shader_include.h"
class ShaderPreprocessor {
public:
enum CompletionType {
COMPLETION_TYPE_NONE,
COMPLETION_TYPE_DIRECTIVE,
COMPLETION_TYPE_PRAGMA_DIRECTIVE,
COMPLETION_TYPE_PRAGMA,
COMPLETION_TYPE_CONDITION,
COMPLETION_TYPE_INCLUDE_PATH,
};
struct FilePosition {
String file;
int line = 0;
};
struct Region {
String file;
int from_line = -1;
int to_line = -1;
bool enabled = false;
Region *parent = nullptr;
};
private:
struct Token {
char32_t text;
int line;
Token();
Token(char32_t p_text, int p_line);
};
// The real preprocessor that understands basic shader and preprocessor language syntax.
class Tokenizer {
public:
String code;
int line;
int index;
int size;
LocalVector<Token> generated;
private:
void add_generated(const Token &p_t);
char32_t next();
public:
int get_line() const;
int get_index() const;
char32_t peek();
int consume_line_continuations(int p_offset);
void get_and_clear_generated(LocalVector<char32_t> *r_out);
void backtrack(char32_t p_what);
LocalVector<Token> advance(char32_t p_what);
void skip_whitespace();
bool consume_empty_line();
String get_identifier(bool *r_is_cursor = nullptr, bool p_started = false);
String peek_identifier();
Token get_token();
Tokenizer(const String &p_code);
};
class CommentRemover {
private:
LocalVector<char32_t> stripped;
String code;
int index;
int line;
int comment_line_open;
int comments_open;
int strings_open;
public:
String get_error() const;
int get_error_line() const;
char32_t peek() const;
bool advance(char32_t p_what);
String strip();
CommentRemover(const String &p_code);
};
struct Define {
Vector<String> arguments;
String body;
};
struct Branch {
Vector<bool> conditions;
Branch *parent = nullptr;
bool else_defined = false;
Branch() {}
Branch(bool p_condition, Branch *p_parent) :
parent(p_parent) {
conditions.push_back(p_condition);
}
};
struct State {
RBMap<String, Define *> defines;
List<Branch> branches;
Branch *current_branch = nullptr;
int condition_depth = 0;
RBSet<String> includes;
List<uint64_t> cyclic_include_hashes; // Holds code hash of includes.
int include_depth = 0;
String current_filename;
String current_shader_type;
String error;
List<FilePosition> include_positions;
bool save_regions = false;
RBMap<String, List<Region>> regions;
Region *previous_region = nullptr;
bool disabled = false;
CompletionType completion_type = COMPLETION_TYPE_NONE;
HashSet<Ref<ShaderInclude>> shader_includes;
};
private:
LocalVector<char32_t> output;
State *state = nullptr;
private:
static bool is_char_word(char32_t p_char);
static bool is_char_space(char32_t p_char);
static bool is_char_end(char32_t p_char);
static String vector_to_string(const LocalVector<char32_t> &p_v, int p_start = 0, int p_end = -1);
static String tokens_to_string(const LocalVector<Token> &p_tokens);
void _set_expected_error(const String &p_what, int p_line) {
set_error(vformat(RTR("Expected a '%s'."), p_what), p_line);
}
void _set_unexpected_token_error(const String &p_what, int p_line) {
set_error(vformat(RTR("Unexpected token: '%s'."), p_what), p_line);
}
void process_directive(Tokenizer *p_tokenizer);
void process_define(Tokenizer *p_tokenizer);
void process_elif(Tokenizer *p_tokenizer);
void process_else(Tokenizer *p_tokenizer);
void process_endif(Tokenizer *p_tokenizer);
void process_error(Tokenizer *p_tokenizer);
void process_if(Tokenizer *p_tokenizer);
void process_ifdef(Tokenizer *p_tokenizer);
void process_ifndef(Tokenizer *p_tokenizer);
void process_include(Tokenizer *p_tokenizer);
void process_pragma(Tokenizer *p_tokenizer);
void process_undef(Tokenizer *p_tokenizer);
void add_region(int p_line, bool p_enabled, Region *p_parent_region);
void start_branch_condition(Tokenizer *p_tokenizer, bool p_success, bool p_continue = false);
Error expand_condition(const String &p_string, int p_line, String &r_result);
void expand_output_macros(int p_start, int p_line);
Error expand_macros(const String &p_string, int p_line, String &r_result);
bool expand_macros_once(const String &p_line, int p_line_number, const RBMap<String, Define *>::Element *p_define_pair, String &r_expanded);
bool find_match(const String &p_string, const String &p_value, int &r_index, int &r_index_start);
void concatenate_macro_body(String &r_body);
String next_directive(Tokenizer *p_tokenizer, const Vector<String> &p_directives);
void add_to_output(const String &p_str);
void set_error(const String &p_error, int p_line);
static Define *create_define(const String &p_body);
void clear_state();
Error preprocess(State *p_state, const String &p_code, String &r_result);
public:
typedef void (*IncludeCompletionFunction)(List<ScriptLanguage::CodeCompletionOption> *);
Error preprocess(const String &p_code, const String &p_filename, String &r_result, String *r_error_text = nullptr, List<FilePosition> *r_error_position = nullptr, List<Region> *r_regions = nullptr, HashSet<Ref<ShaderInclude>> *r_includes = nullptr, List<ScriptLanguage::CodeCompletionOption> *r_completion_options = nullptr, List<ScriptLanguage::CodeCompletionOption> *r_completion_defines = nullptr, IncludeCompletionFunction p_include_completion_func = nullptr);
static void get_keyword_list(List<String> *r_keywords, bool p_include_shader_keywords, bool p_ignore_context_keywords = false);
static void get_pragma_list(List<String> *r_pragmas);
ShaderPreprocessor();
~ShaderPreprocessor();
};
#endif // SHADER_PREPROCESSOR_H