/*  rasterizer_canvas_base_gles2.cpp                                     */


#include "rasterizer_canvas_base_gles2.h"

#include "core/os/os.h"
#include "core/config/project_settings.h"
#include "drivers/gles_common/rasterizer_asserts.h"
#include "servers/rendering/rendering_server_raster.h"

#ifndef GLES_OVER_GL
#define glClearDepth glClearDepthf
#endif

void RasterizerCanvasBaseGLES2::canvas_begin() {
	state.using_transparent_rt = false;

	state.using_modulate = false;

	state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_ATTRIB_MODULATE, false);
	state.canvas_shader.bind();

	int viewport_x, viewport_y, viewport_width, viewport_height;

	if (storage->frame.current_rt) {
		glBindFramebuffer(GL_FRAMEBUFFER, storage->frame.current_rt->fbo);
		state.using_transparent_rt = storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_TRANSPARENT];

		if (storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_DIRECT_TO_SCREEN]) {
			// set Viewport and Scissor when rendering directly to screen
			viewport_width = storage->frame.current_rt->width;
			viewport_height = storage->frame.current_rt->height;
			viewport_x = storage->frame.current_rt->x;
			viewport_y = OS::get_singleton()->get_window_size().height - viewport_height - storage->frame.current_rt->y;
			glScissor(viewport_x, viewport_y, viewport_width, viewport_height);
			glViewport(viewport_x, viewport_y, viewport_width, viewport_height);
			glEnable(GL_SCISSOR_TEST);
		}
	}

	if (storage->frame.clear_request) {
		glClearColor(storage->frame.clear_request_color.r,
				storage->frame.clear_request_color.g,
				storage->frame.clear_request_color.b,
				state.using_transparent_rt ? storage->frame.clear_request_color.a : 1.0);
		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();

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

	glVertexAttrib4f(RS::ARRAY_COLOR, 1, 1, 1, 1);
	glDisableVertexAttribArray(RS::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_local(-(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_local(-(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 RasterizerCanvasBaseGLES2::canvas_end() {
	glBindBuffer(GL_ARRAY_BUFFER, 0);

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

	if (storage->frame.current_rt && storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_DIRECT_TO_SCREEN]) {
		//reset viewport to full window size
		int viewport_width = OS::get_singleton()->get_window_size().width;
		int viewport_height = OS::get_singleton()->get_window_size().height;
		glViewport(0, 0, viewport_width, viewport_height);
		glScissor(0, 0, viewport_width, viewport_height);
	}

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

void RasterizerCanvasBaseGLES2::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 RasterizerCanvasBaseGLES2::_set_texture_rect_mode(bool p_texture_rect, bool p_light_angle, bool p_modulate, bool p_large_vertex) {
	// always set this directly (this could be state checked)
	state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_TEXTURE_RECT, p_texture_rect);

	if (state.using_modulate != p_modulate) {
		state.using_modulate = p_modulate;
		state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_ATTRIB_MODULATE, p_modulate);
	}
}

RasterizerStorageGLES2::Texture *RasterizerCanvasBaseGLES2::_bind_canvas_texture(const RID &p_texture, const RID &p_normal_map) {
	RasterizerStorageGLES2::Texture *tex_return = nullptr;

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

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

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

		} else {
			if (texture->redraw_if_visible) {
				RenderingServerRaster::redraw_request(false);
			}

			texture = texture->get_ptr();

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

			WRAPPED_GL_ACTIVE_TEXTURE(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 = nullptr;

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

	if (p_normal_map == state.current_normal) {
		//do none
		state.canvas_shader.set_uniform(CanvasShaderGLES2::USE_DEFAULT_NORMAL, state.current_normal.is_valid());

	} else if (p_normal_map.is_valid()) {
		RasterizerStorageGLES2::Texture *normal_map = storage->texture_owner.getornull(p_normal_map);

		if (!normal_map) {
			state.current_normal = RID();
			WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0 + storage->config.max_texture_image_units - 2);
			glBindTexture(GL_TEXTURE_2D, storage->resources.normal_tex);
			state.canvas_shader.set_uniform(CanvasShaderGLES2::USE_DEFAULT_NORMAL, false);

		} else {
			if (normal_map->redraw_if_visible) { //check before proxy, because this is usually used with proxies
				RenderingServerRaster::redraw_request(false);
			}

			normal_map = normal_map->get_ptr();

			WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0 + storage->config.max_texture_image_units - 2);
			glBindTexture(GL_TEXTURE_2D, normal_map->tex_id);
			state.current_normal = p_normal_map;
			state.canvas_shader.set_uniform(CanvasShaderGLES2::USE_DEFAULT_NORMAL, true);
		}

	} else {
		state.current_normal = RID();
		WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0 + storage->config.max_texture_image_units - 2);
		glBindTexture(GL_TEXTURE_2D, storage->resources.normal_tex);
		state.canvas_shader.set_uniform(CanvasShaderGLES2::USE_DEFAULT_NORMAL, false);
	}

	return tex_return;
}

void RasterizerCanvasBaseGLES2::draw_window_margins(int *black_margin, RID *black_image) {
	Vector2 window_size = OS::get_singleton()->get_window_size();
	int window_h = window_size.height;
	int window_w = window_size.width;

	glBindFramebuffer(GL_FRAMEBUFFER, storage->system_fbo);
	glViewport(0, 0, window_size.width, window_size.height);
	canvas_begin();

	if (black_image[MARGIN_LEFT].is_valid()) {
		_bind_canvas_texture(black_image[MARGIN_LEFT], RID());
		Size2 sz(storage->texture_get_width(black_image[MARGIN_LEFT]), storage->texture_get_height(black_image[MARGIN_LEFT]));
		draw_generic_textured_rect(Rect2(0, 0, black_margin[MARGIN_LEFT], window_h),
				Rect2(0, 0, (float)black_margin[MARGIN_LEFT] / sz.x, (float)(window_h) / sz.y));
	} else if (black_margin[MARGIN_LEFT]) {
		WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, storage->resources.black_tex);

		draw_generic_textured_rect(Rect2(0, 0, black_margin[MARGIN_LEFT], window_h), Rect2(0, 0, 1, 1));
	}

	if (black_image[MARGIN_RIGHT].is_valid()) {
		_bind_canvas_texture(black_image[MARGIN_RIGHT], RID());
		Size2 sz(storage->texture_get_width(black_image[MARGIN_RIGHT]), storage->texture_get_height(black_image[MARGIN_RIGHT]));
		draw_generic_textured_rect(Rect2(window_w - black_margin[MARGIN_RIGHT], 0, black_margin[MARGIN_RIGHT], window_h),
				Rect2(0, 0, (float)black_margin[MARGIN_RIGHT] / sz.x, (float)window_h / sz.y));
	} else if (black_margin[MARGIN_RIGHT]) {
		WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, storage->resources.black_tex);

		draw_generic_textured_rect(Rect2(window_w - black_margin[MARGIN_RIGHT], 0, black_margin[MARGIN_RIGHT], window_h), Rect2(0, 0, 1, 1));
	}

	if (black_image[MARGIN_TOP].is_valid()) {
		_bind_canvas_texture(black_image[MARGIN_TOP], RID());

		Size2 sz(storage->texture_get_width(black_image[MARGIN_TOP]), storage->texture_get_height(black_image[MARGIN_TOP]));
		draw_generic_textured_rect(Rect2(0, 0, window_w, black_margin[MARGIN_TOP]),
				Rect2(0, 0, (float)window_w / sz.x, (float)black_margin[MARGIN_TOP] / sz.y));

	} else if (black_margin[MARGIN_TOP]) {
		WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, storage->resources.black_tex);

		draw_generic_textured_rect(Rect2(0, 0, window_w, black_margin[MARGIN_TOP]), Rect2(0, 0, 1, 1));
	}

	if (black_image[MARGIN_BOTTOM].is_valid()) {
		_bind_canvas_texture(black_image[MARGIN_BOTTOM], RID());

		Size2 sz(storage->texture_get_width(black_image[MARGIN_BOTTOM]), storage->texture_get_height(black_image[MARGIN_BOTTOM]));
		draw_generic_textured_rect(Rect2(0, window_h - black_margin[MARGIN_BOTTOM], window_w, black_margin[MARGIN_BOTTOM]),
				Rect2(0, 0, (float)window_w / sz.x, (float)black_margin[MARGIN_BOTTOM] / sz.y));

	} else if (black_margin[MARGIN_BOTTOM]) {
		WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0);
		glBindTexture(GL_TEXTURE_2D, storage->resources.black_tex);

		draw_generic_textured_rect(Rect2(0, window_h - black_margin[MARGIN_BOTTOM], window_w, black_margin[MARGIN_BOTTOM]), Rect2(0, 0, 1, 1));
	}

	canvas_end();
}

void RasterizerCanvasBaseGLES2::_bind_quad_buffer() {
	glBindBuffer(GL_ARRAY_BUFFER, data.canvas_quad_vertices);
	glEnableVertexAttribArray(RS::ARRAY_VERTEX);
	glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, 0, nullptr);
}

void RasterizerCanvasBaseGLES2::_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 RasterizerCanvasBaseGLES2::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 GLES2 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) {
		// WRAPPED_GL_ACTIVE_TEXTURE(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 RasterizerCanvasBaseGLES2::_copy_texscreen(const Rect2 &p_rect) {
	state.canvas_texscreen_used = true;

	_copy_screen(p_rect);

	// back to canvas, force rebind
	state.using_texture_rect = false;
	state.canvas_shader.bind();
	_bind_canvas_texture(state.current_tex, state.current_normal);
	_set_uniforms();
}

void RasterizerCanvasBaseGLES2::_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, const float *p_weights, const int *p_bones) {
	glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);

	uint32_t buffer_ofs = 0;
	uint32_t buffer_ofs_after = buffer_ofs + (sizeof(Vector2) * p_vertex_count);
#ifdef DEBUG_ENABLED
	ERR_FAIL_COND(buffer_ofs_after > data.polygon_buffer_size);
#endif

	storage->buffer_orphan_and_upload(data.polygon_buffer_size, 0, sizeof(Vector2) * p_vertex_count, p_vertices, GL_ARRAY_BUFFER, _buffer_upload_usage_flag, true);

	glEnableVertexAttribArray(RS::ARRAY_VERTEX);
	glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), nullptr);
	buffer_ofs = buffer_ofs_after;

	if (p_singlecolor) {
		glDisableVertexAttribArray(RS::ARRAY_COLOR);
		Color m = *p_colors;
		glVertexAttrib4f(RS::ARRAY_COLOR, m.r, m.g, m.b, m.a);
	} else if (!p_colors) {
		glDisableVertexAttribArray(RS::ARRAY_COLOR);
		glVertexAttrib4f(RS::ARRAY_COLOR, 1, 1, 1, 1);
	} else {
		RAST_FAIL_COND(!storage->safe_buffer_sub_data(data.polygon_buffer_size, GL_ARRAY_BUFFER, buffer_ofs, sizeof(Color) * p_vertex_count, p_colors, buffer_ofs_after));
		glEnableVertexAttribArray(RS::ARRAY_COLOR);
		glVertexAttribPointer(RS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, sizeof(Color), CAST_INT_TO_UCHAR_PTR(buffer_ofs));
		buffer_ofs = buffer_ofs_after;
	}

	if (p_uvs) {
		RAST_FAIL_COND(!storage->safe_buffer_sub_data(data.polygon_buffer_size, GL_ARRAY_BUFFER, buffer_ofs, sizeof(Vector2) * p_vertex_count, p_uvs, buffer_ofs_after));
		glEnableVertexAttribArray(RS::ARRAY_TEX_UV);
		glVertexAttribPointer(RS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), CAST_INT_TO_UCHAR_PTR(buffer_ofs));
		buffer_ofs = buffer_ofs_after;
	} else {
		glDisableVertexAttribArray(RS::ARRAY_TEX_UV);
	}

	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.polygon_index_buffer);

	if (storage->config.support_32_bits_indices) { //should check for
#ifdef DEBUG_ENABLED
		ERR_FAIL_COND((sizeof(int) * p_index_count) > data.polygon_index_buffer_size);
#endif
		storage->buffer_orphan_and_upload(data.polygon_index_buffer_size, 0, sizeof(int) * p_index_count, p_indices, GL_ELEMENT_ARRAY_BUFFER, _buffer_upload_usage_flag, true);
		glDrawElements(GL_TRIANGLES, p_index_count, GL_UNSIGNED_INT, nullptr);
		storage->info.render._2d_draw_call_count++;
	} else {
#ifdef DEBUG_ENABLED
		ERR_FAIL_COND((sizeof(uint16_t) * p_index_count) > data.polygon_index_buffer_size);
#endif
		uint16_t *index16 = (uint16_t *)alloca(sizeof(uint16_t) * p_index_count);
		for (int i = 0; i < p_index_count; i++) {
			index16[i] = uint16_t(p_indices[i]);
		}
		storage->buffer_orphan_and_upload(data.polygon_index_buffer_size, 0, sizeof(uint16_t) * p_index_count, index16, GL_ELEMENT_ARRAY_BUFFER, _buffer_upload_usage_flag, true);
		glDrawElements(GL_TRIANGLES, p_index_count, GL_UNSIGNED_SHORT, nullptr);
		storage->info.render._2d_draw_call_count++;
	}

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

void RasterizerCanvasBaseGLES2::_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;
	uint32_t buffer_ofs_after = buffer_ofs + (sizeof(Vector2) * p_vertex_count);
#ifdef DEBUG_ENABLED
	ERR_FAIL_COND(buffer_ofs_after > data.polygon_buffer_size);
#endif
	storage->buffer_orphan_and_upload(data.polygon_buffer_size, 0, sizeof(Vector2) * p_vertex_count, p_vertices, GL_ARRAY_BUFFER, _buffer_upload_usage_flag, true);

	glEnableVertexAttribArray(RS::ARRAY_VERTEX);
	glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), nullptr);
	buffer_ofs = buffer_ofs_after;

	if (p_singlecolor) {
		glDisableVertexAttribArray(RS::ARRAY_COLOR);
		Color m = *p_colors;
		glVertexAttrib4f(RS::ARRAY_COLOR, m.r, m.g, m.b, m.a);
	} else if (!p_colors) {
		glDisableVertexAttribArray(RS::ARRAY_COLOR);
		glVertexAttrib4f(RS::ARRAY_COLOR, 1, 1, 1, 1);
	} else {
		RAST_FAIL_COND(!storage->safe_buffer_sub_data(data.polygon_buffer_size, GL_ARRAY_BUFFER, buffer_ofs, sizeof(Color) * p_vertex_count, p_colors, buffer_ofs_after));
		glEnableVertexAttribArray(RS::ARRAY_COLOR);
		glVertexAttribPointer(RS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, sizeof(Color), CAST_INT_TO_UCHAR_PTR(buffer_ofs));
		buffer_ofs = buffer_ofs_after;
	}

	if (p_uvs) {
		RAST_FAIL_COND(!storage->safe_buffer_sub_data(data.polygon_buffer_size, GL_ARRAY_BUFFER, buffer_ofs, sizeof(Vector2) * p_vertex_count, p_uvs, buffer_ofs_after));
		glEnableVertexAttribArray(RS::ARRAY_TEX_UV);
		glVertexAttribPointer(RS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), CAST_INT_TO_UCHAR_PTR(buffer_ofs));
		buffer_ofs = buffer_ofs_after;
	} else {
		glDisableVertexAttribArray(RS::ARRAY_TEX_UV);
	}

	glDrawArrays(p_primitive, 0, p_vertex_count);
	storage->info.render._2d_draw_call_count++;

	glBindBuffer(GL_ARRAY_BUFFER, 0);
}

void RasterizerCanvasBaseGLES2::_draw_generic_indices(GLuint p_primitive, 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;
	uint32_t buffer_ofs_after = buffer_ofs + (sizeof(Vector2) * p_vertex_count);
#ifdef DEBUG_ENABLED
	ERR_FAIL_COND(buffer_ofs_after > data.polygon_buffer_size);
#endif
	storage->buffer_orphan_and_upload(data.polygon_buffer_size, 0, sizeof(Vector2) * p_vertex_count, p_vertices, GL_ARRAY_BUFFER, _buffer_upload_usage_flag, true);

	glEnableVertexAttribArray(RS::ARRAY_VERTEX);
	glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), nullptr);
	buffer_ofs = buffer_ofs_after;

	if (p_singlecolor) {
		glDisableVertexAttribArray(RS::ARRAY_COLOR);
		Color m = *p_colors;
		glVertexAttrib4f(RS::ARRAY_COLOR, m.r, m.g, m.b, m.a);
	} else if (!p_colors) {
		glDisableVertexAttribArray(RS::ARRAY_COLOR);
		glVertexAttrib4f(RS::ARRAY_COLOR, 1, 1, 1, 1);
	} else {
		RAST_FAIL_COND(!storage->safe_buffer_sub_data(data.polygon_buffer_size, GL_ARRAY_BUFFER, buffer_ofs, sizeof(Color) * p_vertex_count, p_colors, buffer_ofs_after));
		glEnableVertexAttribArray(RS::ARRAY_COLOR);
		glVertexAttribPointer(RS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, sizeof(Color), CAST_INT_TO_UCHAR_PTR(buffer_ofs));
		buffer_ofs = buffer_ofs_after;
	}

	if (p_uvs) {
		RAST_FAIL_COND(!storage->safe_buffer_sub_data(data.polygon_buffer_size, GL_ARRAY_BUFFER, buffer_ofs, sizeof(Vector2) * p_vertex_count, p_uvs, buffer_ofs_after));
		glEnableVertexAttribArray(RS::ARRAY_TEX_UV);
		glVertexAttribPointer(RS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, sizeof(Vector2), CAST_INT_TO_UCHAR_PTR(buffer_ofs));
		buffer_ofs = buffer_ofs_after;
	} else {
		glDisableVertexAttribArray(RS::ARRAY_TEX_UV);
	}

#ifdef RASTERIZER_EXTRA_CHECKS
	// very slow, do not enable in normal use
	for (int n = 0; n < p_index_count; n++) {
		RAST_DEV_DEBUG_ASSERT(p_indices[n] < p_vertex_count);
	}
#endif

	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, data.polygon_index_buffer);

	if (storage->config.support_32_bits_indices) { //should check for
#ifdef DEBUG_ENABLED
		ERR_FAIL_COND((sizeof(int) * p_index_count) > data.polygon_index_buffer_size);
#endif
		storage->buffer_orphan_and_upload(data.polygon_index_buffer_size, 0, sizeof(int) * p_index_count, p_indices, GL_ELEMENT_ARRAY_BUFFER, _buffer_upload_usage_flag, true);
		glDrawElements(p_primitive, p_index_count, GL_UNSIGNED_INT, nullptr);
		storage->info.render._2d_draw_call_count++;
	} else {
#ifdef DEBUG_ENABLED
		ERR_FAIL_COND((sizeof(uint16_t) * p_index_count) > data.polygon_index_buffer_size);
#endif
		uint16_t *index16 = (uint16_t *)alloca(sizeof(uint16_t) * p_index_count);
		for (int i = 0; i < p_index_count; i++) {
			index16[i] = uint16_t(p_indices[i]);
		}
		storage->buffer_orphan_and_upload(data.polygon_index_buffer_size, 0, sizeof(uint16_t) * p_index_count, index16, GL_ELEMENT_ARRAY_BUFFER, _buffer_upload_usage_flag, true);
		glDrawElements(p_primitive, p_index_count, GL_UNSIGNED_SHORT, nullptr);
		storage->info.render._2d_draw_call_count++;
	}

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

void RasterizerCanvasBaseGLES2::_draw_gui_primitive(int p_points, const Vector2 *p_vertices, const Color *p_colors, const Vector2 *p_uvs, const float *p_light_angles) {
	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 light_angle_offset = 0;
	int stride = 2;

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

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

	if (p_light_angles) { //light_angles
		light_angle_offset = stride;
		stride += 1;
	}

	DEV_ASSERT(p_points <= 4);
	float buffer_data[(2 + 2 + 4 + 1) * 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;
		}
	}

	if (p_light_angles) {
		for (int i = 0; i < p_points; i++) {
			buffer_data[stride * i + light_angle_offset + 0] = p_light_angles[i];
		}
	}

	glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);
	storage->buffer_orphan_and_upload(data.polygon_buffer_size, 0, p_points * stride * sizeof(float), buffer_data, GL_ARRAY_BUFFER, _buffer_upload_usage_flag, true);

	glVertexAttribPointer(RS::ARRAY_VERTEX, 2, GL_FLOAT, GL_FALSE, stride * sizeof(float), nullptr);

	if (p_colors) {
		glVertexAttribPointer(RS::ARRAY_COLOR, 4, GL_FLOAT, GL_FALSE, stride * sizeof(float), CAST_INT_TO_UCHAR_PTR(color_offset * sizeof(float)));
		glEnableVertexAttribArray(RS::ARRAY_COLOR);
	}

	if (p_uvs) {
		glVertexAttribPointer(RS::ARRAY_TEX_UV, 2, GL_FLOAT, GL_FALSE, stride * sizeof(float), CAST_INT_TO_UCHAR_PTR(uv_offset * sizeof(float)));
		glEnableVertexAttribArray(RS::ARRAY_TEX_UV);
	}

	if (p_light_angles) {
		glVertexAttribPointer(RS::ARRAY_TANGENT, 1, GL_FLOAT, GL_FALSE, stride * sizeof(float), CAST_INT_TO_UCHAR_PTR(light_angle_offset * sizeof(float)));
		glEnableVertexAttribArray(RS::ARRAY_TANGENT);
	}

	glDrawArrays(prim[p_points], 0, p_points);
	storage->info.render._2d_draw_call_count++;

	if (p_light_angles) {
		// may not be needed
		glDisableVertexAttribArray(RS::ARRAY_TANGENT);
	}

	glBindBuffer(GL_ARRAY_BUFFER, 0);
}

void RasterizerCanvasBaseGLES2::_copy_screen(const Rect2 &p_rect) {
	if (storage->frame.current_rt->flags[RasterizerStorage::RENDER_TARGET_DIRECT_TO_SCREEN]) {
		ERR_PRINT_ONCE("Cannot use screen texture copying in render target set to render direct to screen.");
		return;
	}

	ERR_FAIL_COND_MSG(storage->frame.current_rt->copy_screen_effect.color == 0, "Can't use screen texture copying in a render target configured without copy buffers. To resolve this, change the viewport's Usage property to \"2D\" or \"3D\" instead of \"2D Without Sampling\" or \"3D Without Effects\" respectively.");

	glDisable(GL_BLEND);

	Vector2 wh(storage->frame.current_rt->width, storage->frame.current_rt->height);

	Color copy_section(p_rect.position.x / wh.x, p_rect.position.y / wh.y, p_rect.size.x / wh.x, p_rect.size.y / wh.y);

	if (p_rect != Rect2()) {
		storage->shaders.copy.set_conditional(CopyShaderGLES2::USE_COPY_SECTION, true);
	}

	storage->shaders.copy.set_conditional(CopyShaderGLES2::USE_NO_ALPHA, !state.using_transparent_rt);

	glBindFramebuffer(GL_FRAMEBUFFER, storage->frame.current_rt->copy_screen_effect.fbo);
	WRAPPED_GL_ACTIVE_TEXTURE(GL_TEXTURE0);
	glBindTexture(GL_TEXTURE_2D, storage->frame.current_rt->color);

	storage->shaders.copy.bind();
	storage->shaders.copy.set_uniform(CopyShaderGLES2::COPY_SECTION, copy_section);

	const Vector2 vertpos[4] = {
		Vector2(-1, -1),
		Vector2(-1, 1),
		Vector2(1, 1),
		Vector2(1, -1),
	};

	const Vector2 uvpos[4] = {
		Vector2(0, 0),
		Vector2(0, 1),
		Vector2(1, 1),
		Vector2(1, 0)
	};

	const int indexpos[6] = {
		0, 1, 2,
		2, 3, 0
	};

	_draw_polygon(indexpos, 6, 4, vertpos, uvpos, nullptr, false);

	storage->shaders.copy.set_conditional(CopyShaderGLES2::USE_COPY_SECTION, false);
	storage->shaders.copy.set_conditional(CopyShaderGLES2::USE_NO_ALPHA, false);

	glBindFramebuffer(GL_FRAMEBUFFER, storage->frame.current_rt->fbo); //back to front
	glEnable(GL_BLEND);
}

void RasterizerCanvasBaseGLES2::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 < RS::ARRAY_MAX; i++) {
		glDisableVertexAttribArray(i);
	}
}

void RasterizerCanvasBaseGLES2::initialize() {
	int flag_stream_mode = GLOBAL_GET("rendering/2d/opengl/legacy_stream");
	switch (flag_stream_mode) {
		default: {
			_buffer_upload_usage_flag = GL_STREAM_DRAW;
		} break;
		case 1: {
			_buffer_upload_usage_flag = GL_DYNAMIC_DRAW;
		} break;
		case 2: {
			_buffer_upload_usage_flag = GL_STREAM_DRAW;
		} break;
	}

	// 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 = MAX(poly_size, 2); // minimum 2k, may still see anomalies in editor
		poly_size *= 1024;
		glGenBuffers(1, &data.polygon_buffer);
		glBindBuffer(GL_ARRAY_BUFFER, data.polygon_buffer);
		glBufferData(GL_ARRAY_BUFFER, poly_size, nullptr, 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_buffer_size_kb", 128);
		ProjectSettings::get_singleton()->set_custom_property_info("rendering/limits/buffers/canvas_polygon_index_buffer_size_kb", PropertyInfo(Variant::INT, "rendering/limits/buffers/canvas_polygon_index_buffer_size_kb", PROPERTY_HINT_RANGE, "0,256,1,or_greater"));
		index_size = MAX(index_size, 2);
		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, nullptr, GL_DYNAMIC_DRAW);
		glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);

		data.polygon_index_buffer_size = index_size;
	}

	// 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, nullptr, 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.using_modulate = false;

	_set_texture_rect_mode(true);

	state.canvas_shader.bind();

	state.lens_shader.init();

	state.canvas_shader.set_conditional(CanvasShaderGLES2::USE_PIXEL_SNAP, GLOBAL_DEF("rendering/2d/snapping/use_gpu_pixel_snap", false));

	state.using_transparent_rt = false;
}

void RasterizerCanvasBaseGLES2::finalize() {
}

RasterizerCanvasBaseGLES2::RasterizerCanvasBaseGLES2() {
}