/*************************************************************************/
/*  shader_gles3.cpp                                                     */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2021 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2021 Godot Engine contributors (cf. AUTHORS.md).   */
/*                                                                       */
/* 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.                */
/*************************************************************************/

#include "shader_gles3.h"
#include "drivers/gles3/rasterizer_platforms.h"
#ifdef GLES3_BACKEND_ENABLED

#include "rasterizer_gles3.h"
#include "rasterizer_storage_gles3.h"

#include "core/config/project_settings.h"
#include "core/os/memory.h"
#include "core/string/print_string.h"
#include "core/string/string_builder.h"

// #define DEBUG_OPENGL

// #include "shaders/copy.glsl.gen.h"

#ifdef DEBUG_OPENGL

#define DEBUG_TEST_ERROR(m_section)                                         \
	{                                                                       \
		uint32_t err = glGetError();                                        \
		if (err) {                                                          \
			print_line("OpenGL Error #" + itos(err) + " at: " + m_section); \
		}                                                                   \
	}
#else

#define DEBUG_TEST_ERROR(m_section)

#endif

ShaderGLES3 *ShaderGLES3::active = NULL;

//#define DEBUG_SHADER

#ifdef DEBUG_SHADER

#define DEBUG_PRINT(m_text) print_line(m_text);

#else

#define DEBUG_PRINT(m_text)

#endif

GLint ShaderGLES3::get_uniform_location(int p_index) const {
	ERR_FAIL_COND_V(!version, -1);

	return version->uniform_location[p_index];
}

bool ShaderGLES3::bind() {
	if (active != this || !version || new_conditional_version.key != conditional_version.key) {
		conditional_version = new_conditional_version;
		version = get_current_version();
	} else {
		return false;
	}

	ERR_FAIL_COND_V(!version, false);

	if (!version->ok) { //broken, unable to bind (do not throw error, you saw it before already when it failed compilation).
		glUseProgram(0);
		return false;
	}

	glUseProgram(version->id);

	DEBUG_TEST_ERROR("use program");

	active = this;
	uniforms_dirty = true;

	return true;
}

void ShaderGLES3::unbind() {
	version = NULL;
	glUseProgram(0);
	uniforms_dirty = true;
	active = NULL;
}

static void _display_error_with_code(const String &p_error, const Vector<const char *> &p_code) {
	int line = 1;
	String total_code;

	for (int i = 0; i < p_code.size(); i++) {
		total_code += String(p_code[i]);
	}

	Vector<String> lines = String(total_code).split("\n");

	for (int j = 0; j < lines.size(); j++) {
		print_line(itos(line) + ": " + lines[j]);
		line++;
	}

	ERR_PRINT(p_error);
}

static String _mkid(const String &p_id) {
	String id = "m_" + p_id;
	return id.replace("__", "_dus_"); //doubleunderscore is reserved in glsl
}

ShaderGLES3::Version *ShaderGLES3::get_current_version() {
	if (!valid)
		return nullptr;

	Version *_v = version_map.getptr(conditional_version);

	if (_v) {
		if (conditional_version.code_version != 0) {
			CustomCode *cc = custom_code_map.getptr(conditional_version.code_version);
			ERR_FAIL_COND_V(!cc, _v);
			if (cc->version == _v->code_version)
				return _v;
		} else {
			return _v;
		}
	}

	if (!_v)
		version_map[conditional_version] = Version();

	Version &v = version_map[conditional_version];

	if (!_v) {
		v.uniform_location = memnew_arr(GLint, uniform_count);
	} else {
		if (v.ok) {
			glDeleteShader(v.vert_id);
			glDeleteShader(v.frag_id);
			glDeleteProgram(v.id);
			v.id = 0;
		}
	}

	v.ok = false;

	Vector<const char *> strings;

#ifdef GLES_OVER_GL
	strings.push_back("#version 330\n");
	strings.push_back("#define USE_GLES_OVER_GL\n");
#else
	strings.push_back("#version 300 es\n");
//angle does not like
#ifdef JAVASCRIPT_ENABLED
	strings.push_back("#define USE_HIGHP_PRECISION\n");
#endif

	//if (GLOBAL_GET("rendering/opengl/compatibility/enable_high_float.Android")) {
	// enable USE_HIGHP_PRECISION but safeguarded by an availability check as highp support is optional in OpenGL
	// see Section 4.5.4 of the GLSL_ES_Specification_1.00
	//strings.push_back("#ifdef GL_FRAGMENT_PRECISION_HIGH\n  #define USE_HIGHP_PRECISION\n#endif\n");
	//}

#endif

#ifdef ANDROID_ENABLED
	strings.push_back("#define ANDROID_ENABLED\n");
#endif

	for (int i = 0; i < custom_defines.size(); i++) {
		strings.push_back(custom_defines[i].get_data());
		strings.push_back("\n");
	}

	for (int j = 0; j < conditional_count; j++) {
		bool enable = (conditional_version.version & (1 << j)) > 0;

		if (enable) {
			strings.push_back(conditional_defines[j]);
			DEBUG_PRINT(conditional_defines[j]);
		}
	}

	// keep them around during the function
	CharString code_string;
	CharString code_string2;
	CharString code_globals;

	CustomCode *cc = NULL;

	if (conditional_version.code_version > 0) {
		cc = custom_code_map.getptr(conditional_version.code_version);

		ERR_FAIL_COND_V(!cc, NULL);
		v.code_version = cc->version;
	}

	// program

	v.id = glCreateProgram();
	ERR_FAIL_COND_V(v.id == 0, NULL);

	if (cc) {
		for (int i = 0; i < cc->custom_defines.size(); i++) {
			strings.push_back(cc->custom_defines.write[i]);
			DEBUG_PRINT("CD #" + itos(i) + ": " + String(cc->custom_defines[i].get_data()));
		}
	}

	// vertex shader

	int string_base_size = strings.size();

	strings.push_back(vertex_code0.get_data());

	if (cc) {
		code_globals = cc->vertex_globals.ascii();
		strings.push_back(code_globals.get_data());
	}

	strings.push_back(vertex_code1.get_data());

	if (cc) {
		code_string = cc->vertex.ascii();
		strings.push_back(code_string.get_data());
	}

	strings.push_back(vertex_code2.get_data());

#ifdef DEBUG_SHADER

	DEBUG_PRINT("\nVertex Code:\n\n" + String(code_string.get_data()));

#endif

	v.vert_id = glCreateShader(GL_VERTEX_SHADER);
	glShaderSource(v.vert_id, strings.size(), &strings[0], NULL);
	glCompileShader(v.vert_id);

	GLint status;

	glGetShaderiv(v.vert_id, GL_COMPILE_STATUS, &status);
	if (status == GL_FALSE) {
		GLsizei iloglen;
		glGetShaderiv(v.vert_id, GL_INFO_LOG_LENGTH, &iloglen);

		if (iloglen < 0) {
			glDeleteShader(v.vert_id);
			glDeleteProgram(v.id);
			v.id = 0;

			ERR_PRINT("No OpenGL vertex shader compiler log. What the frick?");
		} else {
			if (iloglen == 0) {
				iloglen = 4096; // buggy driver (Adreno 220+)
			}

			char *ilogmem = (char *)Memory::alloc_static(iloglen + 1);
			ilogmem[iloglen] = '\0';
			glGetShaderInfoLog(v.vert_id, iloglen, &iloglen, ilogmem);

			String err_string = get_shader_name() + ": Vertex shader compilation failed:\n";

			err_string += ilogmem;

			_display_error_with_code(err_string, strings);

			Memory::free_static(ilogmem);
			glDeleteShader(v.vert_id);
			glDeleteProgram(v.id);
			v.id = 0;
		}

		ERR_FAIL_V(NULL);
	}

	strings.resize(string_base_size);

	// fragment shader

	strings.push_back(fragment_code0.get_data());

	if (cc) {
		code_globals = cc->fragment_globals.ascii();
		strings.push_back(code_globals.get_data());
	}

	strings.push_back(fragment_code1.get_data());

	if (cc) {
		code_string = cc->light.ascii();
		strings.push_back(code_string.get_data());
	}

	strings.push_back(fragment_code2.get_data());

	if (cc) {
		code_string2 = cc->fragment.ascii();
		strings.push_back(code_string2.get_data());
	}

	strings.push_back(fragment_code3.get_data());

#ifdef DEBUG_SHADER

	if (cc) {
		DEBUG_PRINT("\nFragment Code:\n\n" + String(cc->fragment_globals));
	}
	DEBUG_PRINT("\nFragment Code:\n\n" + String(code_string.get_data()));
#endif

	v.frag_id = glCreateShader(GL_FRAGMENT_SHADER);
	glShaderSource(v.frag_id, strings.size(), &strings[0], NULL);
	glCompileShader(v.frag_id);

	glGetShaderiv(v.frag_id, GL_COMPILE_STATUS, &status);
	if (status == GL_FALSE) {
		GLsizei iloglen;
		glGetShaderiv(v.frag_id, GL_INFO_LOG_LENGTH, &iloglen);

		if (iloglen < 0) {
			glDeleteShader(v.frag_id);
			glDeleteShader(v.vert_id);
			glDeleteProgram(v.id);
			v.id = 0;

			ERR_PRINT("No OpenGL fragment shader compiler log. What the frick?");
		} else {
			if (iloglen == 0) {
				iloglen = 4096; // buggy driver (Adreno 220+)
			}

			char *ilogmem = (char *)Memory::alloc_static(iloglen + 1);
			ilogmem[iloglen] = '\0';
			glGetShaderInfoLog(v.frag_id, iloglen, &iloglen, ilogmem);

			String err_string = get_shader_name() + ": Fragment shader compilation failed:\n";

			err_string += ilogmem;

			_display_error_with_code(err_string, strings);

			Memory::free_static(ilogmem);
			glDeleteShader(v.frag_id);
			glDeleteShader(v.vert_id);
			glDeleteProgram(v.id);
			v.id = 0;
		}

		ERR_FAIL_V(NULL);
	}

	glAttachShader(v.id, v.frag_id);
	glAttachShader(v.id, v.vert_id);

	// bind the attribute locations. This has to be done before linking so that the
	// linker doesn't assign some random indices

	for (int i = 0; i < attribute_pair_count; i++) {
		glBindAttribLocation(v.id, attribute_pairs[i].index, attribute_pairs[i].name);
	}

	glLinkProgram(v.id);

	glGetProgramiv(v.id, GL_LINK_STATUS, &status);
	if (status == GL_FALSE) {
		GLsizei iloglen;
		glGetProgramiv(v.id, GL_INFO_LOG_LENGTH, &iloglen);

		if (iloglen < 0) {
			glDeleteShader(v.frag_id);
			glDeleteShader(v.vert_id);
			glDeleteProgram(v.id);
			v.id = 0;

			ERR_PRINT("No OpenGL program link log. What the frick?");
			ERR_FAIL_V(NULL);
		}

		if (iloglen == 0) {
			iloglen = 4096; // buggy driver (Adreno 220+)
		}

		char *ilogmem = (char *)Memory::alloc_static(iloglen + 1);
		ilogmem[iloglen] = '\0';
		glGetProgramInfoLog(v.id, iloglen, &iloglen, ilogmem);

		String err_string = get_shader_name() + ": Program linking failed:\n";

		err_string += ilogmem;

		_display_error_with_code(err_string, strings);

		Memory::free_static(ilogmem);
		glDeleteShader(v.frag_id);
		glDeleteShader(v.vert_id);
		glDeleteProgram(v.id);
		v.id = 0;

		ERR_FAIL_V(NULL);
	}

	// get uniform locations

	glUseProgram(v.id);

	for (int i = 0; i < uniform_count; i++) {
		v.uniform_location[i] = glGetUniformLocation(v.id, uniform_names[i]);
	}

	for (int i = 0; i < texunit_pair_count; i++) {
		GLint loc = glGetUniformLocation(v.id, texunit_pairs[i].name);
		if (loc >= 0) {
			if (texunit_pairs[i].index < 0) {
				glUniform1i(loc, max_image_units + texunit_pairs[i].index);
			} else {
				glUniform1i(loc, texunit_pairs[i].index);
			}
		}
	}

	if (cc) {
		// uniforms
		for (int i = 0; i < cc->custom_uniforms.size(); i++) {
			String native_uniform_name = _mkid(cc->custom_uniforms[i]);
			GLint location = glGetUniformLocation(v.id, (native_uniform_name).ascii().get_data());
			v.custom_uniform_locations[cc->custom_uniforms[i]] = location;
		}

		// textures
		for (int i = 0; i < cc->texture_uniforms.size(); i++) {
			String native_uniform_name = _mkid(cc->texture_uniforms[i]);
			GLint location = glGetUniformLocation(v.id, (native_uniform_name).ascii().get_data());
			v.custom_uniform_locations[cc->texture_uniforms[i]] = location;
			glUniform1i(location, i);
		}
	}

	glUseProgram(0);
	v.ok = true;

	if (cc) {
		cc->versions.insert(conditional_version.version);
	}

	return &v;
}

GLint ShaderGLES3::get_uniform_location(const String &p_name) const {
	ERR_FAIL_COND_V(!version, -1);
	return glGetUniformLocation(version->id, p_name.ascii().get_data());
}

void ShaderGLES3::setup(
		const char **p_conditional_defines,
		int p_conditional_count,
		const char **p_uniform_names,
		int p_uniform_count,
		const AttributePair *p_attribute_pairs,
		int p_attribute_count,
		const TexUnitPair *p_texunit_pairs,
		int p_texunit_pair_count,
		const char *p_vertex_code,
		const char *p_fragment_code,
		int p_vertex_code_start,
		int p_fragment_code_start) {
	ERR_FAIL_COND(version);

	conditional_version.key = 0;
	new_conditional_version.key = 0;
	uniform_count = p_uniform_count;
	conditional_count = p_conditional_count;
	conditional_defines = p_conditional_defines;
	uniform_names = p_uniform_names;
	vertex_code = p_vertex_code;
	fragment_code = p_fragment_code;
	texunit_pairs = p_texunit_pairs;
	texunit_pair_count = p_texunit_pair_count;
	vertex_code_start = p_vertex_code_start;
	fragment_code_start = p_fragment_code_start;
	attribute_pairs = p_attribute_pairs;
	attribute_pair_count = p_attribute_count;

	{
		String globals_tag = "\nVERTEX_SHADER_GLOBALS";
		String code_tag = "\nVERTEX_SHADER_CODE";
		String code = vertex_code;
		int cpos = code.find(globals_tag);
		if (cpos == -1) {
			vertex_code0 = code.ascii();
		} else {
			vertex_code0 = code.substr(0, cpos).ascii();
			code = code.substr(cpos + globals_tag.length(), code.length());

			cpos = code.find(code_tag);

			if (cpos == -1) {
				vertex_code1 = code.ascii();
			} else {
				vertex_code1 = code.substr(0, cpos).ascii();
				vertex_code2 = code.substr(cpos + code_tag.length(), code.length()).ascii();
			}
		}
	}

	{
		String globals_tag = "\nFRAGMENT_SHADER_GLOBALS";
		String code_tag = "\nFRAGMENT_SHADER_CODE";
		String light_code_tag = "\nLIGHT_SHADER_CODE";
		String code = fragment_code;
		int cpos = code.find(globals_tag);
		if (cpos == -1) {
			fragment_code0 = code.ascii();
		} else {
			fragment_code0 = code.substr(0, cpos).ascii();
			code = code.substr(cpos + globals_tag.length(), code.length());

			cpos = code.find(light_code_tag);

			String code2;

			if (cpos != -1) {
				fragment_code1 = code.substr(0, cpos).ascii();
				code2 = code.substr(cpos + light_code_tag.length(), code.length());
			} else {
				code2 = code;
			}

			cpos = code2.find(code_tag);
			if (cpos == -1) {
				fragment_code2 = code2.ascii();
			} else {
				fragment_code2 = code2.substr(0, cpos).ascii();
				fragment_code3 = code2.substr(cpos + code_tag.length(), code2.length()).ascii();
			}
		}
	}

	glGetIntegerv(GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS, &max_image_units);

	valid = true;
}

void ShaderGLES3::finish() {
	const VersionKey *V = NULL;

	while ((V = version_map.next(V))) {
		Version &v = version_map[*V];
		glDeleteShader(v.vert_id);
		glDeleteShader(v.frag_id);
		glDeleteProgram(v.id);

		if (v.uniform_location)
			memdelete_arr(v.uniform_location);
	}
}

void ShaderGLES3::clear_caches() {
	const VersionKey *V = NULL;

	while ((V = version_map.next(V))) {
		Version &v = version_map[*V];
		glDeleteShader(v.vert_id);
		glDeleteShader(v.frag_id);
		glDeleteProgram(v.id);
		memdelete_arr(v.uniform_location);
	}

	version_map.clear();

	custom_code_map.clear();
	version = NULL;
	last_custom_code = 1;
	uniforms_dirty = true;
}

uint32_t ShaderGLES3::create_custom_shader() {
	custom_code_map[last_custom_code] = CustomCode();
	custom_code_map[last_custom_code].version = 1;
	return last_custom_code++;
}

void ShaderGLES3::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 Vector<StringName> &p_uniforms,
		const Vector<StringName> &p_texture_uniforms,
		const Vector<CharString> &p_custom_defines) {
	CustomCode *cc = custom_code_map.getptr(p_code_id);
	ERR_FAIL_COND(!cc);

	cc->vertex = p_vertex;
	cc->vertex_globals = p_vertex_globals;
	cc->fragment = p_fragment;
	cc->fragment_globals = p_fragment_globals;
	cc->light = p_light;
	cc->custom_uniforms = p_uniforms;
	cc->custom_defines = p_custom_defines;
	cc->texture_uniforms = p_texture_uniforms;
	cc->version++;
}

void ShaderGLES3::set_custom_shader(uint32_t p_code_id) {
	new_conditional_version.code_version = p_code_id;
}

void ShaderGLES3::free_custom_shader(uint32_t p_code_id) {
	ERR_FAIL_COND(!custom_code_map.has(p_code_id));
	if (conditional_version.code_version == p_code_id) {
		conditional_version.code_version = 0; //do not keep using a version that is going away
		unbind();
	}

	VersionKey key;
	key.code_version = p_code_id;
	for (Set<uint32_t>::Element *E = custom_code_map[p_code_id].versions.front(); E; E = E->next()) {
		key.version = E->get();
		ERR_CONTINUE(!version_map.has(key));
		Version &v = version_map[key];

		glDeleteShader(v.vert_id);
		glDeleteShader(v.frag_id);
		glDeleteProgram(v.id);
		memdelete_arr(v.uniform_location);
		v.id = 0;

		version_map.erase(key);
	}

	custom_code_map.erase(p_code_id);
}

void ShaderGLES3::use_material(void *p_material) {
	RasterizerStorageGLES3::Material *material = (RasterizerStorageGLES3::Material *)p_material;

	if (!material) {
		return;
	}

	if (!material->shader) {
		return;
	}

	Version *v = version_map.getptr(conditional_version);

	// bind uniforms
	for (Map<StringName, ShaderLanguage::ShaderNode::Uniform>::Element *E = material->shader->uniforms.front(); E; E = E->next()) {
		if (E->get().texture_order >= 0)
			continue; // this is a texture, doesn't go here

		Map<StringName, GLint>::Element *L = v->custom_uniform_locations.find(E->key());
		if (!L || L->get() < 0)
			continue; //uniform not valid

		GLuint location = L->get();

		Map<StringName, Variant>::Element *V = material->params.find(E->key());

		if (V) {
			switch (E->get().type) {
				case ShaderLanguage::TYPE_BOOL: {
					bool boolean = V->get();
					glUniform1i(location, boolean ? 1 : 0);
				} break;

				case ShaderLanguage::TYPE_BVEC2: {
					int flags = V->get();
					glUniform2i(location, (flags & 1) ? 1 : 0, (flags & 2) ? 1 : 0);
				} break;

				case ShaderLanguage::TYPE_BVEC3: {
					int flags = V->get();
					glUniform3i(location, (flags & 1) ? 1 : 0, (flags & 2) ? 1 : 0, (flags & 4) ? 1 : 0);

				} break;

				case ShaderLanguage::TYPE_BVEC4: {
					int flags = V->get();
					glUniform4i(location, (flags & 1) ? 1 : 0, (flags & 2) ? 1 : 0, (flags & 4) ? 1 : 0, (flags & 8) ? 1 : 0);

				} break;

				case ShaderLanguage::TYPE_INT:
				case ShaderLanguage::TYPE_UINT: {
					int value = V->get();
					glUniform1i(location, value);
				} break;

				case ShaderLanguage::TYPE_IVEC2:
				case ShaderLanguage::TYPE_UVEC2: {
					Array r = V->get();
					const int count = 2;
					if (r.size() == count) {
						int values[count];
						for (int i = 0; i < count; i++) {
							values[i] = r[i];
						}
						glUniform2i(location, values[0], values[1]);
					}

				} break;

				case ShaderLanguage::TYPE_IVEC3:
				case ShaderLanguage::TYPE_UVEC3: {
					Array r = V->get();
					const int count = 3;
					if (r.size() == count) {
						int values[count];
						for (int i = 0; i < count; i++) {
							values[i] = r[i];
						}
						glUniform3i(location, values[0], values[1], values[2]);
					}

				} break;

				case ShaderLanguage::TYPE_IVEC4:
				case ShaderLanguage::TYPE_UVEC4: {
					Array r = V->get();
					const int count = 4;
					if (r.size() == count) {
						int values[count];
						for (int i = 0; i < count; i++) {
							values[i] = r[i];
						}
						glUniform4i(location, values[0], values[1], values[2], values[3]);
					}

				} break;

				case ShaderLanguage::TYPE_FLOAT: {
					float value = V->get();
					glUniform1f(location, value);

				} break;

				case ShaderLanguage::TYPE_VEC2: {
					Vector2 value = V->get();
					glUniform2f(location, value.x, value.y);
				} break;

				case ShaderLanguage::TYPE_VEC3: {
					Vector3 value = V->get();
					glUniform3f(location, value.x, value.y, value.z);
				} break;

				case ShaderLanguage::TYPE_VEC4: {
					if (V->get().get_type() == Variant::COLOR) {
						Color value = V->get();
						glUniform4f(location, value.r, value.g, value.b, value.a);
					} else if (V->get().get_type() == Variant::QUATERNION) {
						Quaternion value = V->get();
						glUniform4f(location, value.x, value.y, value.z, value.w);
					} else {
						Plane value = V->get();
						glUniform4f(location, value.normal.x, value.normal.y, value.normal.z, value.d);
					}

				} break;

				case ShaderLanguage::TYPE_MAT2: {
					Transform2D tr = V->get();
					GLfloat matrix[4] = {
						/* build a 16x16 matrix */
						tr.elements[0][0],
						tr.elements[0][1],
						tr.elements[1][0],
						tr.elements[1][1],
					};
					glUniformMatrix2fv(location, 1, GL_FALSE, matrix);

				} break;

				case ShaderLanguage::TYPE_MAT3: {
					Basis val = V->get();

					GLfloat mat[9] = {
						val.elements[0][0],
						val.elements[1][0],
						val.elements[2][0],
						val.elements[0][1],
						val.elements[1][1],
						val.elements[2][1],
						val.elements[0][2],
						val.elements[1][2],
						val.elements[2][2],
					};

					glUniformMatrix3fv(location, 1, GL_FALSE, mat);

				} break;

				case ShaderLanguage::TYPE_MAT4: {
					Transform2D tr = V->get();
					GLfloat matrix[16] = { /* build a 16x16 matrix */
						tr.elements[0][0],
						tr.elements[0][1],
						0,
						0,
						tr.elements[1][0],
						tr.elements[1][1],
						0,
						0,
						0,
						0,
						1,
						0,
						tr.elements[2][0],
						tr.elements[2][1],
						0,
						1
					};

					glUniformMatrix4fv(location, 1, GL_FALSE, matrix);

				} break;

				default: {
					ERR_PRINT("ShaderNode type missing, bug?");
				} break;
			}
		} else if (E->get().default_value.size()) {
			const Vector<ShaderLanguage::ConstantNode::Value> &values = E->get().default_value;
			switch (E->get().type) {
				case ShaderLanguage::TYPE_BOOL: {
					glUniform1i(location, values[0].boolean);
				} break;

				case ShaderLanguage::TYPE_BVEC2: {
					glUniform2i(location, values[0].boolean, values[1].boolean);
				} break;

				case ShaderLanguage::TYPE_BVEC3: {
					glUniform3i(location, values[0].boolean, values[1].boolean, values[2].boolean);
				} break;

				case ShaderLanguage::TYPE_BVEC4: {
					glUniform4i(location, values[0].boolean, values[1].boolean, values[2].boolean, values[3].boolean);
				} break;

				case ShaderLanguage::TYPE_INT: {
					glUniform1i(location, values[0].sint);
				} break;

				case ShaderLanguage::TYPE_IVEC2: {
					glUniform2i(location, values[0].sint, values[1].sint);
				} break;

				case ShaderLanguage::TYPE_IVEC3: {
					glUniform3i(location, values[0].sint, values[1].sint, values[2].sint);
				} break;

				case ShaderLanguage::TYPE_IVEC4: {
					glUniform4i(location, values[0].sint, values[1].sint, values[2].sint, values[3].sint);
				} break;

				case ShaderLanguage::TYPE_UINT: {
					glUniform1i(location, values[0].uint);
				} break;

				case ShaderLanguage::TYPE_UVEC2: {
					glUniform2i(location, values[0].uint, values[1].uint);
				} break;

				case ShaderLanguage::TYPE_UVEC3: {
					glUniform3i(location, values[0].uint, values[1].uint, values[2].uint);
				} break;

				case ShaderLanguage::TYPE_UVEC4: {
					glUniform4i(location, values[0].uint, values[1].uint, values[2].uint, values[3].uint);
				} break;

				case ShaderLanguage::TYPE_FLOAT: {
					glUniform1f(location, values[0].real);
				} break;

				case ShaderLanguage::TYPE_VEC2: {
					glUniform2f(location, values[0].real, values[1].real);
				} break;

				case ShaderLanguage::TYPE_VEC3: {
					glUniform3f(location, values[0].real, values[1].real, values[2].real);
				} break;

				case ShaderLanguage::TYPE_VEC4: {
					glUniform4f(location, values[0].real, values[1].real, values[2].real, values[3].real);
				} break;

				case ShaderLanguage::TYPE_MAT2: {
					GLfloat mat[4];

					for (int i = 0; i < 4; i++) {
						mat[i] = values[i].real;
					}

					glUniformMatrix2fv(location, 1, GL_FALSE, mat);
				} break;

				case ShaderLanguage::TYPE_MAT3: {
					GLfloat mat[9];

					for (int i = 0; i < 9; i++) {
						mat[i] = values[i].real;
					}

					glUniformMatrix3fv(location, 1, GL_FALSE, mat);

				} break;

				case ShaderLanguage::TYPE_MAT4: {
					GLfloat mat[16];

					for (int i = 0; i < 16; i++) {
						mat[i] = values[i].real;
					}

					glUniformMatrix4fv(location, 1, GL_FALSE, mat);

				} break;

				case ShaderLanguage::TYPE_SAMPLER2D: {
				} break;

					/*
				case ShaderLanguage::TYPE_SAMPLEREXT: {
				} break;
*/
				case ShaderLanguage::TYPE_ISAMPLER2D: {
				} break;

				case ShaderLanguage::TYPE_USAMPLER2D: {
				} break;

				case ShaderLanguage::TYPE_SAMPLERCUBE: {
				} break;

				case ShaderLanguage::TYPE_SAMPLER2DARRAY:
				case ShaderLanguage::TYPE_ISAMPLER2DARRAY:
				case ShaderLanguage::TYPE_USAMPLER2DARRAY:
				case ShaderLanguage::TYPE_SAMPLER3D:
				case ShaderLanguage::TYPE_ISAMPLER3D:
				case ShaderLanguage::TYPE_USAMPLER3D: {
					// Not implemented in OpenGL
				} break;

				case ShaderLanguage::TYPE_VOID: {
					// Nothing to do?
				} break;
				default: {
					ERR_PRINT("ShaderNode type missing, bug?");
				} break;
			}
		} else { //zero

			switch (E->get().type) {
				case ShaderLanguage::TYPE_BOOL: {
					glUniform1i(location, GL_FALSE);
				} break;

				case ShaderLanguage::TYPE_BVEC2: {
					glUniform2i(location, GL_FALSE, GL_FALSE);
				} break;

				case ShaderLanguage::TYPE_BVEC3: {
					glUniform3i(location, GL_FALSE, GL_FALSE, GL_FALSE);
				} break;

				case ShaderLanguage::TYPE_BVEC4: {
					glUniform4i(location, GL_FALSE, GL_FALSE, GL_FALSE, GL_FALSE);
				} break;

				case ShaderLanguage::TYPE_INT: {
					glUniform1i(location, 0);
				} break;

				case ShaderLanguage::TYPE_IVEC2: {
					glUniform2i(location, 0, 0);
				} break;

				case ShaderLanguage::TYPE_IVEC3: {
					glUniform3i(location, 0, 0, 0);
				} break;

				case ShaderLanguage::TYPE_IVEC4: {
					glUniform4i(location, 0, 0, 0, 0);
				} break;

				case ShaderLanguage::TYPE_UINT: {
					glUniform1i(location, 0);
				} break;

				case ShaderLanguage::TYPE_UVEC2: {
					glUniform2i(location, 0, 0);
				} break;

				case ShaderLanguage::TYPE_UVEC3: {
					glUniform3i(location, 0, 0, 0);
				} break;

				case ShaderLanguage::TYPE_UVEC4: {
					glUniform4i(location, 0, 0, 0, 0);
				} break;

				case ShaderLanguage::TYPE_FLOAT: {
					glUniform1f(location, 0);
				} break;

				case ShaderLanguage::TYPE_VEC2: {
					glUniform2f(location, 0, 0);
				} break;

				case ShaderLanguage::TYPE_VEC3: {
					glUniform3f(location, 0, 0, 0);
				} break;

				case ShaderLanguage::TYPE_VEC4: {
					glUniform4f(location, 0, 0, 0, 0);
				} break;

				case ShaderLanguage::TYPE_MAT2: {
					GLfloat mat[4] = { 0, 0, 0, 0 };

					glUniformMatrix2fv(location, 1, GL_FALSE, mat);
				} break;

				case ShaderLanguage::TYPE_MAT3: {
					GLfloat mat[9] = { 0, 0, 0, 0, 0, 0, 0, 0, 0 };

					glUniformMatrix3fv(location, 1, GL_FALSE, mat);

				} break;

				case ShaderLanguage::TYPE_MAT4: {
					GLfloat mat[16] = { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0 };

					glUniformMatrix4fv(location, 1, GL_FALSE, mat);

				} break;

				case ShaderLanguage::TYPE_SAMPLER2D: {
				} break;

					/*
				case ShaderLanguage::TYPE_SAMPLEREXT: {
				} break;
*/

				case ShaderLanguage::TYPE_ISAMPLER2D: {
				} break;

				case ShaderLanguage::TYPE_USAMPLER2D: {
				} break;

				case ShaderLanguage::TYPE_SAMPLERCUBE: {
				} break;

				case ShaderLanguage::TYPE_SAMPLER2DARRAY:
				case ShaderLanguage::TYPE_ISAMPLER2DARRAY:
				case ShaderLanguage::TYPE_USAMPLER2DARRAY:
				case ShaderLanguage::TYPE_SAMPLER3D:
				case ShaderLanguage::TYPE_ISAMPLER3D:
				case ShaderLanguage::TYPE_USAMPLER3D: {
					// Not implemented in OpenGL
				} break;

				case ShaderLanguage::TYPE_VOID: {
					// Nothing to do?
				} break;
				default: {
					ERR_PRINT("ShaderNode type missing, bug?");
				} break;
			}
		}
	}
}

ShaderGLES3::ShaderGLES3() {
	version = NULL;
	last_custom_code = 1;
	uniforms_dirty = true;
}

ShaderGLES3::~ShaderGLES3() {
	finish();
}

#endif // GLES3_BACKEND_ENABLED