/*************************************************************************/
/*  rasterizer_canvas_gles2.cpp                                          */
/*************************************************************************/
/*                       This file is part of:                           */
/*                           GODOT ENGINE                                */
/*                      https://godotengine.org                          */
/*************************************************************************/
/* Copyright (c) 2007-2018 Juan Linietsky, Ariel Manzur.                 */
/* Copyright (c) 2014-2018 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 "rasterizer_canvas_gles2.h"

#include "core/os/os.h"
#include "core/project_settings.h"
#include "rasterizer_scene_gles2.h"
#include "servers/visual/visual_server_raster.h"

#ifndef GLES_OVER_GL
#define glClearDepth glClearDepthf
#endif

RID RasterizerCanvasGLES2::light_internal_create() {

	return RID();
}

void RasterizerCanvasGLES2::light_internal_update(RID p_rid, Light *p_light) {
}

void RasterizerCanvasGLES2::light_internal_free(RID p_rid) {
}

void RasterizerCanvasGLES2::_set_uniforms() {

	state.canvas_shader.set_uniform(CanvasShaderGLES2::PROJECTION_MATRIX, state.uniforms.projection_matrix);
	state.canvas_shader.set_uniform(CanvasShaderGLES2::MODELVIEW_MATRIX, state.uniforms.modelview_matrix);
	state.canvas_shader.set_uniform(CanvasShaderGLES2::EXTRA_MATRIX, state.uniforms.extra_matrix);

	state.canvas_shader.set_uniform(CanvasShaderGLES2::FINAL_MODULATE, state.uniforms.final_modulate);

	state.canvas_shader.set_uniform(CanvasShaderGLES2::TIME, storage->frame.time[0]);

	if (storage->frame.current_rt) {
		Vector2 screen_pixel_size;
		screen_pixel_size.x = 1.0 / storage->frame.current_rt->width;
		screen_pixel_size.y = 1.0 / storage->frame.current_rt->height;

		state.canvas_shader.set_uniform(CanvasShaderGLES2::SCREEN_PIXEL_SIZE, screen_pixel_size);
	}
}

void RasterizerCanvasGLES2::canvas_begin() {

	state.canvas_shader.bind();
	if (storage->frame.current_rt) {
		glBindFramebuffer(GL_FRAMEBUFFER, storage->frame.current_rt->fbo);
		glColorMask(1, 1, 1, 1);
	}

	if (storage->frame.clear_request) {
		glColorMask(true, true, true, true);
		glClearColor(storage->frame.clear_request_color.r,
				storage->frame.clear_request_color.g,
				storage->frame.clear_request_color.b,
				storage->frame.clear_request_color.a);
		glClear(GL_COLOR_BUFFER_BIT);
		storage->frame.clear_request = false;
	}

	/*
	if (storage->frame.current_rt) {
		glBindFramebuffer(GL_FRAMEBUFFER, storage->frame.current_rt->fbo);
		glColorMask(1, 1, 1, 1);
	}
	*/

	reset_canvas();

	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, storage->resources.white_tex);

	glVertexAttrib4f(VS::ARRAY_COLOR, 1, 1, 1, 1);
	glDisableVertexAttribArray(VS::ARRAY_COLOR);

	// set up default uniforms

	Transform canvas_transform;

	if (storage->frame.current_rt) {

		float csy = 1.0;
		if (storage->frame.current_rt && storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_VFLIP]) {
			csy = -1.0;
		}
		canvas_transform.translate(-(storage->frame.current_rt->width / 2.0f), -(storage->frame.current_rt->height / 2.0f), 0.0f);
		canvas_transform.scale(Vector3(2.0f / storage->frame.current_rt->width, csy * -2.0f / storage->frame.current_rt->height, 1.0f));
	} else {
		Vector2 ssize = OS::get_singleton()->get_window_size();
		canvas_transform.translate(-(ssize.width / 2.0f), -(ssize.height / 2.0f), 0.0f);
		canvas_transform.scale(Vector3(2.0f / ssize.width, -2.0f / ssize.height, 1.0f));
	}

	state.uniforms.projection_matrix = canvas_transform;

	state.uniforms.final_modulate = Color(1, 1, 1, 1);

	state.uniforms.modelview_matrix = Transform2D();
	state.uniforms.extra_matrix = Transform2D();

	_set_uniforms();
	_bind_quad_buffer();
}

void RasterizerCanvasGLES2::canvas_end() {

	glBindBuffer(GL_ARRAY_BUFFER, 0);

	for (int i = 0; i < VS::ARRAY_MAX; i++) {
		glDisableVertexAttribArray(i);
	}

	state.using_texture_rect = false;
	state.using_ninepatch = false;
}

RasterizerStorageGLES2::Texture *RasterizerCanvasGLES2::_bind_canvas_texture(const RID &p_texture, const RID &p_normal_map) {

	RasterizerStorageGLES2::Texture *tex_return = NULL;

	if (p_texture.is_valid()) {

		RasterizerStorageGLES2::Texture *texture = storage->texture_owner.getornull(p_texture);

		if (!texture) {
			state.current_tex = RID();
			state.current_tex_ptr = NULL;

			glActiveTexture(GL_TEXTURE0 + storage->config.max_texture_image_units - 1);
			glBindTexture(GL_TEXTURE_2D, storage->resources.white_tex);

		} else {

			texture = texture->get_ptr();

			if (texture->redraw_if_visible) {
				VisualServerRaster::redraw_request();
			}

			if (texture->render_target) {
				texture->render_target->used_in_frame = true;
			}

			glActiveTexture(GL_TEXTURE0 + storage->config.max_texture_image_units - 1);
			glBindTexture(GL_TEXTURE_2D, texture->tex_id);

			state.current_tex = p_texture;
			state.current_tex_ptr = texture;

			tex_return = texture;
		}
	} else {
		state.current_tex = RID();
		state.current_tex_ptr = NULL;

		glActiveTexture(GL_TEXTURE0 + storage->config.max_texture_image_units - 1);
		glBindTexture(GL_TEXTURE_2D, storage->resources.white_tex);
	}

	return tex_return;
}

void RasterizerCanvasGLES2::_set_texture_rect_mode(bool p_enable, bool p_ninepatch) {
}

void RasterizerCanvasGLES2::_draw_polygon(const int *p_indices, int p_index_count, int p_vertex_count, const Vector2 *p_vertices, const Vector2 *p_uvs, const Color *p_colors, bool p_singlecolor) {

	glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);

	uint32_t buffer_ofs = 0;

	glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(Vector2) * p_vertex_count, p_vertices);
	glEnableVertexAttribArray(VS::ARRAY_VERTEX);
	glVertexAttribPointer(VS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), NULL);
	buffer_ofs += sizeof(Vector2) * p_vertex_count;

	if (p_singlecolor) {
		glDisableVertexAttribArray(VS::ARRAY_COLOR);
		Color m = *p_colors;
		glVertexAttrib4f(VS::ARRAY_COLOR, m.r, m.g, m.b, m.a);
	} else if (!p_colors) {
		glDisableVertexAttribArray(VS::ARRAY_COLOR);
		glVertexAttrib4f(VS::ARRAY_COLOR, 1, 1, 1, 1);
	} else {
		glBufferSubData(GL_ARRAY_BUFFER, buffer_ofs, sizeof(Color) * p_vertex_count, p_colors);
		glEnableVertexAttribArray(VS::ARRAY_COLOR);
		glVertexAttribPointer(VS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, sizeof(Color), ((uint8_t *)0) + buffer_ofs);
		buffer_ofs += sizeof(Color) * p_vertex_count;
	}

	if (p_uvs) {
		glBufferSubData(GL_ARRAY_BUFFER, buffer_ofs, sizeof(Vector2) * p_vertex_count, p_uvs);
		glEnableVertexAttribArray(VS::ARRAY_TEX_UV);
		glVertexAttribPointer(VS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), ((uint8_t *)0) + buffer_ofs);
		buffer_ofs += sizeof(Vector2) * p_vertex_count;
	} else {
		glDisableVertexAttribArray(VS::ARRAY_TEX_UV);
	}

	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.polygon_index_buffer);
	glBufferSubData(GL_ELEMENT_ARRAY_BUFFER, 0, sizeof(int) * p_index_count, p_indices);

	glDrawElements(GL_TRIANGLES, p_index_count, GL_UNSIGNED_INT, 0);

	glBindBuffer(GL_ARRAY_BUFFER, 0);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}

void RasterizerCanvasGLES2::_draw_generic(GLuint p_primitive, int p_vertex_count, const Vector2 *p_vertices, const Vector2 *p_uvs, const Color *p_colors, bool p_singlecolor) {

	glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);

	uint32_t buffer_ofs = 0;

	glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(Vector2) * p_vertex_count, p_vertices);
	glEnableVertexAttribArray(VS::ARRAY_VERTEX);
	glVertexAttribPointer(VS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), (uint8_t *)0);
	buffer_ofs += sizeof(Vector2) * p_vertex_count;

	if (p_singlecolor) {
		glDisableVertexAttribArray(VS::ARRAY_COLOR);
		Color m = *p_colors;
		glVertexAttrib4f(VS::ARRAY_COLOR, m.r, m.g, m.b, m.a);
	} else if (!p_colors) {
		glDisableVertexAttribArray(VS::ARRAY_COLOR);
		glVertexAttrib4f(VS::ARRAY_COLOR, 1, 1, 1, 1);
	} else {
		glBufferSubData(GL_ARRAY_BUFFER, buffer_ofs, sizeof(Color) * p_vertex_count, p_colors);
		glEnableVertexAttribArray(VS::ARRAY_COLOR);
		glVertexAttribPointer(VS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, sizeof(Color), ((uint8_t *)0) + buffer_ofs);
		buffer_ofs += sizeof(Color) * p_vertex_count;
	}

	if (p_uvs) {
		glBufferSubData(GL_ARRAY_BUFFER, buffer_ofs, sizeof(Vector2) * p_vertex_count, p_uvs);
		glEnableVertexAttribArray(VS::ARRAY_TEX_UV);
		glVertexAttribPointer(VS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), ((uint8_t *)0) + buffer_ofs);
	} else {
		glDisableVertexAttribArray(VS::ARRAY_TEX_UV);
	}

	glDrawArrays(p_primitive, 0, p_vertex_count);

	glBindBuffer(GL_ARRAY_BUFFER, 0);
}

void RasterizerCanvasGLES2::_draw_gui_primitive(int p_points, const Vector2 *p_vertices, const Color *p_colors, const Vector2 *p_uvs) {

	static const GLenum prim[5] = { GL_POINTS, GL_POINTS, GL_LINES, GL_TRIANGLES, GL_TRIANGLE_FAN };

	int color_offset = 0;
	int uv_offset = 0;
	int stride = 2;

	if (p_colors) {
		color_offset = stride;
		stride += 4;
	}

	if (p_uvs) {
		uv_offset = stride;
		stride += 2;
	}

	float buffer_data[(2 + 2 + 4) * 4];

	for (int i = 0; i < p_points; i++) {
		buffer_data[stride * i + 0] = p_vertices[i].x;
		buffer_data[stride * i + 1] = p_vertices[i].y;
	}

	if (p_colors) {
		for (int i = 0; i < p_points; i++) {
			buffer_data[stride * i + color_offset + 0] = p_colors[i].r;
			buffer_data[stride * i + color_offset + 1] = p_colors[i].g;
			buffer_data[stride * i + color_offset + 2] = p_colors[i].b;
			buffer_data[stride * i + color_offset + 3] = p_colors[i].a;
		}
	}

	if (p_uvs) {
		for (int i = 0; i < p_points; i++) {
			buffer_data[stride * i + uv_offset + 0] = p_uvs[i].x;
			buffer_data[stride * i + uv_offset + 1] = p_uvs[i].y;
		}
	}

	glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);
	glBufferSubData(GL_ARRAY_BUFFER, 0, p_points * stride * 4 * sizeof(float), buffer_data);

	glVertexAttribPointer(VS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, stride * sizeof(float), NULL);

	if (p_colors) {
		glVertexAttribPointer(VS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, stride * sizeof(float), (uint8_t *)0 + color_offset * sizeof(float));
		glEnableVertexAttribArray(VS::ARRAY_COLOR);
	}

	if (p_uvs) {
		glVertexAttribPointer(VS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, stride * sizeof(float), (uint8_t *)0 + uv_offset * sizeof(float));
		glEnableVertexAttribArray(VS::ARRAY_TEX_UV);
	}

	glDrawArrays(prim[p_points], 0, p_points);

	glBindBuffer(GL_ARRAY_BUFFER, 0);
}

void RasterizerCanvasGLES2::_canvas_item_render_commands(Item *p_item, Item *current_clip, bool &reclip, RasterizerStorageGLES2::Material *p_material) {

	int command_count = p_item->commands.size();
	Item::Command **commands = p_item->commands.ptrw();

	for (int i = 0; i < command_count; i++) {

		Item::Command *command = commands[i];

		switch (command->type) {

			case Item::Command::TYPE_LINE: {

				Item::CommandLine *line = static_cast<Item::CommandLine *>(command);

				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);
				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				_bind_canvas_texture(RID(), RID());

				glDisableVertexAttribArray(VS::ARRAY_COLOR);
				glVertexAttrib4fv(VS::ARRAY_COLOR, line->color.components);

				state.canvas_shader.set_uniform(CanvasShaderGLES2::MODELVIEW_MATRIX, state.uniforms.modelview_matrix);

				if (line->width <= 1) {
					Vector2 verts[2] = {
						Vector2(line->from.x, line->from.y),
						Vector2(line->to.x, line->to.y)
					};

					_draw_gui_primitive(2, verts, NULL, NULL);
				} else {
					Vector2 t = (line->from - line->to).normalized().tangent() * line->width * 0.5;

					Vector2 verts[4] = {
						line->from - t,
						line->from + t,
						line->to + t,
						line->to - t
					};

					_draw_gui_primitive(4, verts, NULL, NULL);
				}
			} break;

			case Item::Command::TYPE_RECT: {

				Item::CommandRect *r = static_cast<Item::CommandRect *>(command);

				glDisableVertexAttribArray(VS::ARRAY_COLOR);
				glVertexAttrib4fv(VS::ARRAY_COLOR, r->modulate.components);

#if 1
				//more compatible
				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);

				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				Size2 abs_size = r->rect.size.abs();
				Vector2 points[4] = {
					r->rect.position,
					r->rect.position + Vector2(abs_size.x, 0.0),
					r->rect.position + abs_size,
					r->rect.position + Vector2(0.0, abs_size.y),
				};

				if (r->rect.size.x < 0) {
					SWAP(points[0], points[1]);
					SWAP(points[2], points[3]);
				}
				if (r->rect.size.y < 0) {
					SWAP(points[0], points[3]);
					SWAP(points[1], points[2]);
				}

				RasterizerStorageGLES2::Texture *texture = _bind_canvas_texture(r->texture, r->normal_map);

				if (texture) {
					Size2 texpixel_size(1.0 / texture->width, 1.0 / texture->height);

					Rect2 src_rect = (r->flags & CANVAS_RECT_REGION) ? Rect2(r->source.position * texpixel_size, r->source.size * texpixel_size) : Rect2(0, 0, 1, 1);

					Vector2 uvs[4] = {
						src_rect.position,
						src_rect.position + Vector2(src_rect.size.x, 0.0),
						src_rect.position + src_rect.size,
						src_rect.position + Vector2(0.0, src_rect.size.y),
					};

					if (r->flags & CANVAS_RECT_FLIP_H) {
						SWAP(uvs[0], uvs[1]);
						SWAP(uvs[2], uvs[3]);
					}
					if (r->flags & CANVAS_RECT_FLIP_V) {
						SWAP(uvs[0], uvs[3]);
						SWAP(uvs[1], uvs[2]);
					}

					if (r->flags & CANVAS_RECT_TRANSPOSE) {
						SWAP(uvs[1], uvs[3]);
					}

					state.canvas_shader.set_uniform(CanvasShaderGLES2::COLOR_TEXPIXEL_SIZE, texpixel_size);

					bool untile = false;

					if (r->flags & CANVAS_RECT_TILE && !(texture->flags & VS::TEXTURE_FLAG_REPEAT)) {
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
						untile = true;
					}

					_draw_gui_primitive(4, points, NULL, uvs);

					if (untile) {
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
					}
				} else {
					state.canvas_shader.set_uniform(CanvasShaderGLES2::COLOR_TEXPIXEL_SIZE, Vector2());
					_draw_gui_primitive(4, points, NULL, NULL);
				}

#else
				//disabled because it fails on buggy nvidia drivers
				_bind_quad_buffer();

				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, true);

				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				RasterizerStorageGLES2::Texture *tex = _bind_canvas_texture(r->texture, r->normal_map);

				if (!tex) {
					Rect2 dst_rect = Rect2(r->rect.position, r->rect.size);

					if (dst_rect.size.width < 0) {
						dst_rect.position.x += dst_rect.size.width;
						dst_rect.size.width *= -1;
					}
					if (dst_rect.size.height < 0) {
						dst_rect.position.y += dst_rect.size.height;
						dst_rect.size.height *= -1;
					}

					state.canvas_shader.set_uniform(CanvasShaderGLES2::DST_RECT, Color(dst_rect.position.x, dst_rect.position.y, dst_rect.size.x, dst_rect.size.y));
					state.canvas_shader.set_uniform(CanvasShaderGLES2::SRC_RECT, Color(0, 0, 1, 1));

					glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
				} else {

					bool untile = false;

					if (r->flags & CANVAS_RECT_TILE && !(tex->flags & VS::TEXTURE_FLAG_REPEAT)) {
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
						untile = true;
					}

					Size2 texpixel_size(1.0 / tex->width, 1.0 / tex->height);
					Rect2 src_rect = (r->flags & CANVAS_RECT_REGION) ? Rect2(r->source.position * texpixel_size, r->source.size * texpixel_size) : Rect2(0, 0, 1, 1);

					Rect2 dst_rect = Rect2(r->rect.position, r->rect.size);

					if (dst_rect.size.width < 0) {
						dst_rect.position.x += dst_rect.size.width;
						dst_rect.size.width *= -1;
					}
					if (dst_rect.size.height < 0) {
						dst_rect.position.y += dst_rect.size.height;
						dst_rect.size.height *= -1;
					}

					if (r->flags & CANVAS_RECT_FLIP_H) {
						src_rect.size.x *= -1;
					}

					if (r->flags & CANVAS_RECT_FLIP_V) {
						src_rect.size.y *= -1;
					}

					if (r->flags & CANVAS_RECT_TRANSPOSE) {
						dst_rect.size.x *= -1; // Encoding in the dst_rect.z uniform
					}

					state.canvas_shader.set_uniform(CanvasShaderGLES2::COLOR_TEXPIXEL_SIZE, texpixel_size);

					state.canvas_shader.set_uniform(CanvasShaderGLES2::DST_RECT, Color(dst_rect.position.x, dst_rect.position.y, dst_rect.size.x, dst_rect.size.y));
					state.canvas_shader.set_uniform(CanvasShaderGLES2::SRC_RECT, Color(src_rect.position.x, src_rect.position.y, src_rect.size.x, src_rect.size.y));

					glDrawArrays(GL_TRIANGLE_FAN, 0, 4);

					if (untile) {
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
						glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
					}
				}

				glBindBuffer(GL_ARRAY_BUFFER, 0);
				glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
#endif
			} break;

			case Item::Command::TYPE_NINEPATCH: {

				Item::CommandNinePatch *np = static_cast<Item::CommandNinePatch *>(command);

				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);
				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				glDisableVertexAttribArray(VS::ARRAY_COLOR);
				glVertexAttrib4fv(VS::ARRAY_COLOR, np->color.components);

				RasterizerStorageGLES2::Texture *tex = _bind_canvas_texture(np->texture, np->normal_map);

				if (!tex) {
					// FIXME: Handle textureless ninepatch gracefully
					WARN_PRINT("NinePatch without texture not supported yet in GLES2 backend, skipping.");
					continue;
				}

				Size2 texpixel_size(1.0 / tex->width, 1.0 / tex->height);

				// state.canvas_shader.set_uniform(CanvasShaderGLES2::MODELVIEW_MATRIX, state.uniforms.modelview_matrix);
				state.canvas_shader.set_uniform(CanvasShaderGLES2::COLOR_TEXPIXEL_SIZE, texpixel_size);

				Rect2 source = np->source;
				if (source.size.x == 0 && source.size.y == 0) {
					source.size.x = tex->width;
					source.size.y = tex->height;
				}

				// prepare vertex buffer

				// this buffer contains [ POS POS UV UV ] *

				float buffer[16 * 2 + 16 * 2];

				{

					// first row

					buffer[(0 * 4 * 4) + 0] = np->rect.position.x;
					buffer[(0 * 4 * 4) + 1] = np->rect.position.y;

					buffer[(0 * 4 * 4) + 2] = source.position.x * texpixel_size.x;
					buffer[(0 * 4 * 4) + 3] = source.position.y * texpixel_size.y;

					buffer[(0 * 4 * 4) + 4] = np->rect.position.x + np->margin[MARGIN_LEFT];
					buffer[(0 * 4 * 4) + 5] = np->rect.position.y;

					buffer[(0 * 4 * 4) + 6] = (source.position.x + np->margin[MARGIN_LEFT]) * texpixel_size.x;
					buffer[(0 * 4 * 4) + 7] = source.position.y * texpixel_size.y;

					buffer[(0 * 4 * 4) + 8] = np->rect.position.x + np->rect.size.x - np->margin[MARGIN_RIGHT];
					buffer[(0 * 4 * 4) + 9] = np->rect.position.y;

					buffer[(0 * 4 * 4) + 10] = (source.position.x + source.size.x - np->margin[MARGIN_RIGHT]) * texpixel_size.x;
					buffer[(0 * 4 * 4) + 11] = source.position.y * texpixel_size.y;

					buffer[(0 * 4 * 4) + 12] = np->rect.position.x + np->rect.size.x;
					buffer[(0 * 4 * 4) + 13] = np->rect.position.y;

					buffer[(0 * 4 * 4) + 14] = (source.position.x + source.size.x) * texpixel_size.x;
					buffer[(0 * 4 * 4) + 15] = source.position.y * texpixel_size.y;

					// second row

					buffer[(1 * 4 * 4) + 0] = np->rect.position.x;
					buffer[(1 * 4 * 4) + 1] = np->rect.position.y + np->margin[MARGIN_TOP];

					buffer[(1 * 4 * 4) + 2] = source.position.x * texpixel_size.x;
					buffer[(1 * 4 * 4) + 3] = (source.position.y + np->margin[MARGIN_TOP]) * texpixel_size.y;

					buffer[(1 * 4 * 4) + 4] = np->rect.position.x + np->margin[MARGIN_LEFT];
					buffer[(1 * 4 * 4) + 5] = np->rect.position.y + np->margin[MARGIN_TOP];

					buffer[(1 * 4 * 4) + 6] = (source.position.x + np->margin[MARGIN_LEFT]) * texpixel_size.x;
					buffer[(1 * 4 * 4) + 7] = (source.position.y + np->margin[MARGIN_TOP]) * texpixel_size.y;

					buffer[(1 * 4 * 4) + 8] = np->rect.position.x + np->rect.size.x - np->margin[MARGIN_RIGHT];
					buffer[(1 * 4 * 4) + 9] = np->rect.position.y + np->margin[MARGIN_TOP];

					buffer[(1 * 4 * 4) + 10] = (source.position.x + source.size.x - np->margin[MARGIN_RIGHT]) * texpixel_size.x;
					buffer[(1 * 4 * 4) + 11] = (source.position.y + np->margin[MARGIN_TOP]) * texpixel_size.y;

					buffer[(1 * 4 * 4) + 12] = np->rect.position.x + np->rect.size.x;
					buffer[(1 * 4 * 4) + 13] = np->rect.position.y + np->margin[MARGIN_TOP];

					buffer[(1 * 4 * 4) + 14] = (source.position.x + source.size.x) * texpixel_size.x;
					buffer[(1 * 4 * 4) + 15] = (source.position.y + np->margin[MARGIN_TOP]) * texpixel_size.y;

					// third row

					buffer[(2 * 4 * 4) + 0] = np->rect.position.x;
					buffer[(2 * 4 * 4) + 1] = np->rect.position.y + np->rect.size.y - np->margin[MARGIN_BOTTOM];

					buffer[(2 * 4 * 4) + 2] = source.position.x * texpixel_size.x;
					buffer[(2 * 4 * 4) + 3] = (source.position.y + source.size.y - np->margin[MARGIN_BOTTOM]) * texpixel_size.y;

					buffer[(2 * 4 * 4) + 4] = np->rect.position.x + np->margin[MARGIN_LEFT];
					buffer[(2 * 4 * 4) + 5] = np->rect.position.y + np->rect.size.y - np->margin[MARGIN_BOTTOM];

					buffer[(2 * 4 * 4) + 6] = (source.position.x + np->margin[MARGIN_LEFT]) * texpixel_size.x;
					buffer[(2 * 4 * 4) + 7] = (source.position.y + source.size.y - np->margin[MARGIN_BOTTOM]) * texpixel_size.y;

					buffer[(2 * 4 * 4) + 8] = np->rect.position.x + np->rect.size.x - np->margin[MARGIN_RIGHT];
					buffer[(2 * 4 * 4) + 9] = np->rect.position.y + np->rect.size.y - np->margin[MARGIN_BOTTOM];

					buffer[(2 * 4 * 4) + 10] = (source.position.x + source.size.x - np->margin[MARGIN_RIGHT]) * texpixel_size.x;
					buffer[(2 * 4 * 4) + 11] = (source.position.y + source.size.y - np->margin[MARGIN_BOTTOM]) * texpixel_size.y;

					buffer[(2 * 4 * 4) + 12] = np->rect.position.x + np->rect.size.x;
					buffer[(2 * 4 * 4) + 13] = np->rect.position.y + np->rect.size.y - np->margin[MARGIN_BOTTOM];

					buffer[(2 * 4 * 4) + 14] = (source.position.x + source.size.x) * texpixel_size.x;
					buffer[(2 * 4 * 4) + 15] = (source.position.y + source.size.y - np->margin[MARGIN_BOTTOM]) * texpixel_size.y;

					// fourth row

					buffer[(3 * 4 * 4) + 0] = np->rect.position.x;
					buffer[(3 * 4 * 4) + 1] = np->rect.position.y + np->rect.size.y;

					buffer[(3 * 4 * 4) + 2] = source.position.x * texpixel_size.x;
					buffer[(3 * 4 * 4) + 3] = (source.position.y + source.size.y) * texpixel_size.y;

					buffer[(3 * 4 * 4) + 4] = np->rect.position.x + np->margin[MARGIN_LEFT];
					buffer[(3 * 4 * 4) + 5] = np->rect.position.y + np->rect.size.y;

					buffer[(3 * 4 * 4) + 6] = (source.position.x + np->margin[MARGIN_LEFT]) * texpixel_size.x;
					buffer[(3 * 4 * 4) + 7] = (source.position.y + source.size.y) * texpixel_size.y;

					buffer[(3 * 4 * 4) + 8] = np->rect.position.x + np->rect.size.x - np->margin[MARGIN_RIGHT];
					buffer[(3 * 4 * 4) + 9] = np->rect.position.y + np->rect.size.y;

					buffer[(3 * 4 * 4) + 10] = (source.position.x + source.size.x - np->margin[MARGIN_RIGHT]) * texpixel_size.x;
					buffer[(3 * 4 * 4) + 11] = (source.position.y + source.size.y) * texpixel_size.y;

					buffer[(3 * 4 * 4) + 12] = np->rect.position.x + np->rect.size.x;
					buffer[(3 * 4 * 4) + 13] = np->rect.position.y + np->rect.size.y;

					buffer[(3 * 4 * 4) + 14] = (source.position.x + source.size.x) * texpixel_size.x;
					buffer[(3 * 4 * 4) + 15] = (source.position.y + source.size.y) * texpixel_size.y;
				}

				glBindBuffer(GL_ARRAY_BUFFER, data.ninepatch_vertices);
				glBufferSubData(GL_ARRAY_BUFFER, 0, sizeof(float) * (16 + 16) * 2, buffer);

				glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.ninepatch_elements);

				glEnableVertexAttribArray(VS::ARRAY_VERTEX);
				glEnableVertexAttribArray(VS::ARRAY_TEX_UV);

				glVertexAttribPointer(VS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), NULL);
				glVertexAttribPointer(VS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, 4 * sizeof(float), (uint8_t *)0 + (sizeof(float) * 2));

				glDrawElements(GL_TRIANGLES, 18 * 3 - (np->draw_center ? 0 : 6), GL_UNSIGNED_BYTE, NULL);

				glBindBuffer(GL_ARRAY_BUFFER, 0);
				glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);

			} break;

			case Item::Command::TYPE_CIRCLE: {

				Item::CommandCircle *circle = static_cast<Item::CommandCircle *>(command);

				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);

				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				static const int num_points = 32;

				Vector2 points[num_points + 1];
				points[num_points] = circle->pos;

				int indices[num_points * 3];

				for (int i = 0; i < num_points; i++) {
					points[i] = circle->pos + Vector2(Math::sin(i * Math_PI * 2.0 / num_points), Math::cos(i * Math_PI * 2.0 / num_points)) * circle->radius;
					indices[i * 3 + 0] = i;
					indices[i * 3 + 1] = (i + 1) % num_points;
					indices[i * 3 + 2] = num_points;
				}

				_bind_canvas_texture(RID(), RID());

				_draw_polygon(indices, num_points * 3, num_points + 1, points, NULL, &circle->color, true);
			} break;

			case Item::Command::TYPE_POLYGON: {

				Item::CommandPolygon *polygon = static_cast<Item::CommandPolygon *>(command);

				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);

				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				RasterizerStorageGLES2::Texture *texture = _bind_canvas_texture(polygon->texture, polygon->normal_map);

				if (texture) {
					Size2 texpixel_size(1.0 / texture->width, 1.0 / texture->height);
					state.canvas_shader.set_uniform(CanvasShaderGLES2::COLOR_TEXPIXEL_SIZE, texpixel_size);
				}

				_draw_polygon(polygon->indices.ptr(), polygon->count, polygon->points.size(), polygon->points.ptr(), polygon->uvs.ptr(), polygon->colors.ptr(), polygon->colors.size() == 1);
			} break;

			case Item::Command::TYPE_POLYLINE: {
				Item::CommandPolyLine *pline = static_cast<Item::CommandPolyLine *>(command);

				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);

				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				_bind_canvas_texture(RID(), RID());

				if (pline->triangles.size()) {
					_draw_generic(GL_TRIANGLE_STRIP, pline->triangles.size(), pline->triangles.ptr(), NULL, pline->triangle_colors.ptr(), pline->triangle_colors.size() == 1);
				} else {
					if (pline->multiline) {
						int todo = pline->lines.size() / 2;
						int max_per_call = data.polygon_buffer_size / (sizeof(real_t) * 4);
						int offset = 0;

						while (todo) {
							int to_draw = MIN(max_per_call, todo);
							_draw_generic(GL_LINES, to_draw * 2, &pline->lines.ptr()[offset], NULL, pline->line_colors.size() == 1 ? pline->line_colors.ptr() : &pline->line_colors.ptr()[offset], pline->line_colors.size() == 1);
							todo -= to_draw;
							offset += to_draw * 2;
						}
					} else {
						_draw_generic(GL_LINES, pline->lines.size(), pline->lines.ptr(), NULL, pline->line_colors.ptr(), pline->line_colors.size() == 1);
					}
				}
			} break;

			case Item::Command::TYPE_PRIMITIVE: {

				Item::CommandPrimitive *primitive = static_cast<Item::CommandPrimitive *>(command);
				state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, false);

				if (state.canvas_shader.bind()) {
					_set_uniforms();
					state.canvas_shader.use_material((void *)p_material);
				}

				ERR_CONTINUE(primitive->points.size() < 1);

				RasterizerStorageGLES2::Texture *texture = _bind_canvas_texture(primitive->texture, primitive->normal_map);

				if (texture) {
					Size2 texpixel_size(1.0 / texture->width, 1.0 / texture->height);
					state.canvas_shader.set_uniform(CanvasShaderGLES2::COLOR_TEXPIXEL_SIZE, texpixel_size);
				}

				if (primitive->colors.size() == 1 && primitive->points.size() > 1) {
					Color c = primitive->colors[0];
					glVertexAttrib4f(VS::ARRAY_COLOR, c.r, c.g, c.b, c.a);
				} else if (primitive->colors.empty()) {
					glVertexAttrib4f(VS::ARRAY_COLOR, 1, 1, 1, 1);
				}

				_draw_gui_primitive(primitive->points.size(), primitive->points.ptr(), primitive->colors.ptr(), primitive->uvs.ptr());
			} break;

			case Item::Command::TYPE_TRANSFORM: {
				Item::CommandTransform *transform = static_cast<Item::CommandTransform *>(command);
				state.uniforms.extra_matrix = transform->xform;
				state.canvas_shader.set_uniform(CanvasShaderGLES2::EXTRA_MATRIX, state.uniforms.extra_matrix);
			} break;

			case Item::Command::TYPE_PARTICLES: {

			} break;

			case Item::Command::TYPE_CLIP_IGNORE: {

				Item::CommandClipIgnore *ci = static_cast<Item::CommandClipIgnore *>(command);
				if (current_clip) {
					if (ci->ignore != reclip) {
						if (ci->ignore) {
							glDisable(GL_SCISSOR_TEST);
							reclip = true;
						} else {
							glEnable(GL_SCISSOR_TEST);

							int x = current_clip->final_clip_rect.position.x;
							int y = storage->frame.current_rt->height - (current_clip->final_clip_rect.position.y + current_clip->final_clip_rect.size.y);
							int w = current_clip->final_clip_rect.size.x;
							int h = current_clip->final_clip_rect.size.y;

							if (storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_VFLIP])
								y = current_clip->final_clip_rect.position.y;

							glScissor(x, y, w, h);

							reclip = false;
						}
					}
				}

			} break;

			default: {
				// FIXME: Proper error handling if relevant
				//print_line("other");
			} break;
		}
	}
}

void RasterizerCanvasGLES2::_copy_texscreen(const Rect2 &p_rect) {

	// This isn't really working yet, so disabling for now.
}

void RasterizerCanvasGLES2::canvas_render_items(Item *p_item_list, int p_z, const Color &p_modulate, Light *p_light, const Transform2D &p_base_transform) {

	Item *current_clip = NULL;

	RasterizerStorageGLES2::Shader *shader_cache = NULL;

	bool rebind_shader = true;

	state.current_tex = RID();
	state.current_tex_ptr = NULL;
	state.current_normal = RID();

	glActiveTexture(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, storage->resources.white_tex);

	int last_blend_mode = -1;

	RID canvas_last_material = RID();

	while (p_item_list) {

		Item *ci = p_item_list;

		if (current_clip != ci->final_clip_owner) {

			current_clip = ci->final_clip_owner;

			if (current_clip) {
				glEnable(GL_SCISSOR_TEST);
				int y = storage->frame.current_rt->height - (current_clip->final_clip_rect.position.y + current_clip->final_clip_rect.size.y);
				if (storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_VFLIP])
					y = current_clip->final_clip_rect.position.y;
				glScissor(current_clip->final_clip_rect.position.x, y, current_clip->final_clip_rect.size.width, current_clip->final_clip_rect.size.height);
			} else {
				glDisable(GL_SCISSOR_TEST);
			}
		}

		// TODO: copy back buffer

		if (ci->copy_back_buffer) {
			if (ci->copy_back_buffer->full) {
				_copy_texscreen(Rect2());
			} else {
				_copy_texscreen(ci->copy_back_buffer->rect);
			}
		}

		Item *material_owner = ci->material_owner ? ci->material_owner : ci;

		RID material = material_owner->material;
		RasterizerStorageGLES2::Material *material_ptr = storage->material_owner.getornull(material);

		if (material != canvas_last_material || rebind_shader) {

			RasterizerStorageGLES2::Shader *shader_ptr = NULL;

			if (material_ptr) {
				shader_ptr = material_ptr->shader;

				if (shader_ptr && shader_ptr->mode != VS::SHADER_CANVAS_ITEM) {
					shader_ptr = NULL; // not a canvas item shader, don't use.
				}
			}

			if (shader_ptr) {
				if (shader_ptr->canvas_item.uses_screen_texture) {
					_copy_texscreen(Rect2());
				}

				if (shader_ptr != shader_cache) {

					if (shader_ptr->canvas_item.uses_time) {
						VisualServerRaster::redraw_request();
					}

					state.canvas_shader.set_custom_shader(shader_ptr->custom_code_id);
					state.canvas_shader.bind();
				}

				int tc = material_ptr->textures.size();
				Pair<StringName, RID> *textures = material_ptr->textures.ptrw();

				ShaderLanguage::ShaderNode::Uniform::Hint *texture_hints = shader_ptr->texture_hints.ptrw();

				for (int i = 0; i < tc; i++) {

					glActiveTexture(GL_TEXTURE0 + i);

					RasterizerStorageGLES2::Texture *t = storage->texture_owner.getornull(textures[i].second);

					if (!t) {

						switch (texture_hints[i]) {
							case ShaderLanguage::ShaderNode::Uniform::HINT_BLACK_ALBEDO:
							case ShaderLanguage::ShaderNode::Uniform::HINT_BLACK: {
								glBindTexture(GL_TEXTURE_2D, storage->resources.black_tex);
							} break;
							case ShaderLanguage::ShaderNode::Uniform::HINT_ANISO: {
								glBindTexture(GL_TEXTURE_2D, storage->resources.aniso_tex);
							} break;
							case ShaderLanguage::ShaderNode::Uniform::HINT_NORMAL: {
								glBindTexture(GL_TEXTURE_2D, storage->resources.normal_tex);
							} break;
							default: {
								glBindTexture(GL_TEXTURE_2D, storage->resources.white_tex);
							} break;
						}

						continue;
					}

					t = t->get_ptr();

					if (t->redraw_if_visible) {
						VisualServerRaster::redraw_request();
					}

					glBindTexture(t->target, t->tex_id);
				}

			} else {
				state.canvas_shader.set_custom_shader(0);
				state.canvas_shader.bind();
			}
			state.canvas_shader.use_material((void *)material_ptr);

			shader_cache = shader_ptr;

			canvas_last_material = material;

			rebind_shader = false;
		}

		int blend_mode = shader_cache ? shader_cache->canvas_item.blend_mode : RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MIX;
		bool unshaded = (shader_cache && blend_mode != RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MIX);
		bool reclip = false;

		if (last_blend_mode != blend_mode) {

			switch (blend_mode) {

				case RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MIX: {
					glBlendEquation(GL_FUNC_ADD);
					if (storage->frame.current_rt && storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_TRANSPARENT]) {
						glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
					} else {
						glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
					}

				} break;
				case RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_ADD: {

					glBlendEquation(GL_FUNC_ADD);
					glBlendFunc(GL_SRC_ALPHA, GL_ONE);

				} break;
				case RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_SUB: {

					glBlendEquation(GL_FUNC_REVERSE_SUBTRACT);
					glBlendFunc(GL_SRC_ALPHA, GL_ONE);
				} break;
				case RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_MUL: {
					glBlendEquation(GL_FUNC_ADD);
					glBlendFunc(GL_DST_COLOR, GL_ZERO);
				} break;
				case RasterizerStorageGLES2::Shader::CanvasItem::BLEND_MODE_PMALPHA: {
					glBlendEquation(GL_FUNC_ADD);
					glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
				} break;
			}
		}

		state.uniforms.final_modulate = unshaded ? ci->final_modulate : Color(ci->final_modulate.r * p_modulate.r, ci->final_modulate.g * p_modulate.g, ci->final_modulate.b * p_modulate.b, ci->final_modulate.a * p_modulate.a);

		state.uniforms.modelview_matrix = ci->final_transform;
		state.uniforms.extra_matrix = Transform2D();

		_set_uniforms();

		_canvas_item_render_commands(p_item_list, NULL, reclip, material_ptr);

		rebind_shader = true; // hacked in for now.

		if (reclip) {
			glEnable(GL_SCISSOR_TEST);
			int y = storage->frame.current_rt->height - (current_clip->final_clip_rect.position.y + current_clip->final_clip_rect.size.y);
			if (storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_VFLIP])
				y = current_clip->final_clip_rect.position.y;
			glScissor(current_clip->final_clip_rect.position.x, y, current_clip->final_clip_rect.size.width, current_clip->final_clip_rect.size.height);
		}

		p_item_list = p_item_list->next;
	}

	if (current_clip) {
		glDisable(GL_SCISSOR_TEST);
	}
}

void RasterizerCanvasGLES2::canvas_debug_viewport_shadows(Light *p_lights_with_shadow) {
}

void RasterizerCanvasGLES2::canvas_light_shadow_buffer_update(RID p_buffer, const Transform2D &p_light_xform, int p_light_mask, float p_near, float p_far, LightOccluderInstance *p_occluders, CameraMatrix *p_xform_cache) {
}

void RasterizerCanvasGLES2::reset_canvas() {

	glDisable(GL_CULL_FACE);
	glDisable(GL_DEPTH_TEST);
	glDisable(GL_SCISSOR_TEST);
	glDisable(GL_DITHER);
	glEnable(GL_BLEND);

	if (storage->frame.current_rt && storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_TRANSPARENT]) {
		glBlendFuncSeparate(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA, GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
	} else {
		glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
	}

	// bind the back buffer to a texture so shaders can use it.
	// It should probably use texture unit -3 (as GLES3 does as well) but currently that's buggy.
	// keeping this for now as there's nothing else that uses texture unit 2
	// TODO ^
	if (storage->frame.current_rt) {
		// glActiveTexture(GL_TEXTURE0 + 2);
		// glBindTexture(GL_TEXTURE_2D, storage->frame.current_rt->copy_screen_effect.color);
	}

	glBindBuffer(GL_ARRAY_BUFFER, 0);
	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
}

void RasterizerCanvasGLES2::_bind_quad_buffer() {
	glBindBuffer(GL_ARRAY_BUFFER, data.canvas_quad_vertices);
	glEnableVertexAttribArray(VS::ARRAY_VERTEX);
	glVertexAttribPointer(VS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, 0, NULL);
}
void RasterizerCanvasGLES2::draw_generic_textured_rect(const Rect2 &p_rect, const Rect2 &p_src) {

	state.canvas_shader.set_uniform(CanvasShaderGLES2::DST_RECT, Color(p_rect.position.x, p_rect.position.y, p_rect.size.x, p_rect.size.y));
	state.canvas_shader.set_uniform(CanvasShaderGLES2::SRC_RECT, Color(p_src.position.x, p_src.position.y, p_src.size.x, p_src.size.y));

	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);
}

void RasterizerCanvasGLES2::draw_lens_distortion_rect(const Rect2 &p_rect, float p_k1, float p_k2, const Vector2 &p_eye_center, float p_oversample) {
	Vector2 half_size;
	if (storage->frame.current_rt) {
		half_size = Vector2(storage->frame.current_rt->width, storage->frame.current_rt->height);
	} else {
		half_size = OS::get_singleton()->get_window_size();
	}
	half_size *= 0.5;
	Vector2 offset((p_rect.position.x - half_size.x) / half_size.x, (p_rect.position.y - half_size.y) / half_size.y);
	Vector2 scale(p_rect.size.x / half_size.x, p_rect.size.y / half_size.y);

	float aspect_ratio = p_rect.size.x / p_rect.size.y;

	// setup our lens shader
	state.lens_shader.bind();
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::OFFSET, offset);
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::SCALE, scale);
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::K1, p_k1);
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::K2, p_k2);
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::EYE_CENTER, p_eye_center);
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::UPSCALE, p_oversample);
	state.lens_shader.set_uniform(LensDistortedShaderGLES2::ASPECT_RATIO, aspect_ratio);

	// bind our quad buffer
	_bind_quad_buffer();

	// and draw
	glDrawArrays(GL_TRIANGLE_FAN, 0, 4);

	// and cleanup
	glBindBuffer(GL_ARRAY_BUFFER, 0);

	for (int i = 0; i < VS::ARRAY_MAX; i++) {
		glDisableVertexAttribArray(i);
	}
}

void RasterizerCanvasGLES2::draw_window_margins(int *black_margin, RID *black_image) {
}

void RasterizerCanvasGLES2::initialize() {

	// quad buffer
	{
		glGenBuffers(1, &data.canvas_quad_vertices);
		glBindBuffer(GL_ARRAY_BUFFER, data.canvas_quad_vertices);

		const float qv[8] = {
			0, 0,
			0, 1,
			1, 1,
			1, 0
		};

		glBufferData(GL_ARRAY_BUFFER, sizeof(float) * 8, qv, GL_STATIC_DRAW);

		glBindBuffer(GL_ARRAY_BUFFER, 0);
	}

	// polygon buffer
	{
		uint32_t poly_size = GLOBAL_DEF("rendering/limits/buffers/canvas_polygon_buffer_size_kb", 128);
		ProjectSettings::get_singleton()->set_custom_property_info("rendering/limits/buffers/canvas_polygon_buffer_size_kb", PropertyInfo(Variant::INT, "rendering/limits/buffers/canvas_polygon_buffer_size_kb", PROPERTY_HINT_RANGE, "0,256,1,or_greater"));
		poly_size *= 1024;
		poly_size = MAX(poly_size, (2 + 2 + 4) * 4 * sizeof(float));
		glGenBuffers(1, &data.polygon_buffer);
		glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);
		glBufferData(GL_ARRAY_BUFFER, poly_size, NULL, GL_DYNAMIC_DRAW);

		data.polygon_buffer_size = poly_size;

		glBindBuffer(GL_ARRAY_BUFFER, 0);

		uint32_t index_size = GLOBAL_DEF("rendering/limits/buffers/canvas_polygon_index_size_kb", 128);
		ProjectSettings::get_singleton()->set_custom_property_info("rendering/limits/buffers/canvas_polygon_index_size_kb", PropertyInfo(Variant::INT, "rendering/limits/buffers/canvas_polygon_index_size_kb", PROPERTY_HINT_RANGE, "0,256,1,or_greater"));
		index_size *= 1024; // kb
		glGenBuffers(1, &data.polygon_index_buffer);
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.polygon_index_buffer);
		glBufferData(GL_ELEMENT_ARRAY_BUFFER, index_size, NULL, GL_DYNAMIC_DRAW);
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
	}

	// ninepatch buffers
	{
		// array buffer
		glGenBuffers(1, &data.ninepatch_vertices);
		glBindBuffer(GL_ARRAY_BUFFER, data.ninepatch_vertices);

		glBufferData(GL_ARRAY_BUFFER, sizeof(float) * (16 + 16) * 2, NULL, GL_DYNAMIC_DRAW);

		glBindBuffer(GL_ARRAY_BUFFER, 0);

		// element buffer
		glGenBuffers(1, &data.ninepatch_elements);
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.ninepatch_elements);

#define _EIDX(y, x) (y * 4 + x)
		uint8_t elems[3 * 2 * 9] = {

			// first row

			_EIDX(0, 0), _EIDX(0, 1), _EIDX(1, 1),
			_EIDX(1, 1), _EIDX(1, 0), _EIDX(0, 0),

			_EIDX(0, 1), _EIDX(0, 2), _EIDX(1, 2),
			_EIDX(1, 2), _EIDX(1, 1), _EIDX(0, 1),

			_EIDX(0, 2), _EIDX(0, 3), _EIDX(1, 3),
			_EIDX(1, 3), _EIDX(1, 2), _EIDX(0, 2),

			// second row

			_EIDX(1, 0), _EIDX(1, 1), _EIDX(2, 1),
			_EIDX(2, 1), _EIDX(2, 0), _EIDX(1, 0),

			// the center one would be here, but we'll put it at the end
			// so it's easier to disable the center and be able to use
			// one draw call for both

			_EIDX(1, 2), _EIDX(1, 3), _EIDX(2, 3),
			_EIDX(2, 3), _EIDX(2, 2), _EIDX(1, 2),

			// third row

			_EIDX(2, 0), _EIDX(2, 1), _EIDX(3, 1),
			_EIDX(3, 1), _EIDX(3, 0), _EIDX(2, 0),

			_EIDX(2, 1), _EIDX(2, 2), _EIDX(3, 2),
			_EIDX(3, 2), _EIDX(3, 1), _EIDX(2, 1),

			_EIDX(2, 2), _EIDX(2, 3), _EIDX(3, 3),
			_EIDX(3, 3), _EIDX(3, 2), _EIDX(2, 2),

			// center field

			_EIDX(1, 1), _EIDX(1, 2), _EIDX(2, 2),
			_EIDX(2, 2), _EIDX(2, 1), _EIDX(1, 1)
		};
#undef _EIDX

		glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(elems), elems, GL_STATIC_DRAW);

		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
	}

	state.canvas_shader.init();

	state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, true);

	state.canvas_shader.bind();

	state.lens_shader.init();

	state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_PIXEL_SNAP, GLOBAL_DEF("rendering/quality/2d/use_pixel_snap", false));
}

void RasterizerCanvasGLES2::finalize() {
}

RasterizerCanvasGLES2::RasterizerCanvasGLES2() {
}