lite_particles2d

framework/opengl_renderer/src/mm/opengl/components/lite_particles2d.hpp

@@ -0,0 +1,26 @@
+#pragma once
+
+#include <glm/vec2.hpp>
+
+#include <queue> // tmp
+
+namespace MM::Components {
+
+	// not intended to be a component
+	// see LiteParticles2DUploadQueue
+	struct LiteParticle2D {
+		uint32_t type_id {0u}; // entt::hashed_string, ResourceManager
+
+		glm::vec2 pos {0.f, 0.f};
+		glm::vec2 vel {0.f, 0.f};
+
+		float age {0.f};
+	};
+
+	struct LiteParticles2DUploadQueue {
+		// TODO: vector
+		std::queue<LiteParticle2D> queue;
+	};
+
+} // MM::Components
+

framework/opengl_renderer/src/mm/opengl/lite_particles2d_type.hpp

@@ -0,0 +1,95 @@
+#pragma once
+
+#include <glm/vec4.hpp>
+
+#include <nlohmann/json.hpp>
+
+#include <mm/components/serialize/json_glm.hpp>
+#include <vector>
+
+namespace MM::OpenGL {
+
+	struct LiteParticles2DType {
+		struct Compute {
+			float age_delta;
+
+			glm::vec2 force_vec;
+
+			float turbulence;
+			float turbulence_noise_scale;
+			float turbulence_individuality;
+			float turbulence_time_scale;
+
+			float dampening;
+
+			static constexpr size_t _member_count = 8;
+		} compute;
+
+		struct Render {
+			glm::vec4 color_start;
+			glm::vec4 color_end;
+
+			float size_start;
+			float size_end;
+
+			static constexpr size_t _member_count = 10;
+		} render;
+
+		// naive, prob fine, not time critical
+		void upload(std::vector<float>& comp_vec, std::vector<float>& rend_vec) const {
+			{
+				comp_vec.push_back(compute.age_delta);
+
+				comp_vec.push_back(compute.force_vec.x);
+				comp_vec.push_back(compute.force_vec.y);
+
+				comp_vec.push_back(compute.turbulence);
+				comp_vec.push_back(compute.turbulence_noise_scale);
+				comp_vec.push_back(compute.turbulence_individuality);
+				comp_vec.push_back(compute.turbulence_time_scale);
+
+				comp_vec.push_back(compute.dampening);
+			}
+
+			{
+				rend_vec.push_back(render.color_start.r);
+				rend_vec.push_back(render.color_start.g);
+				rend_vec.push_back(render.color_start.b);
+				rend_vec.push_back(render.color_start.a);
+
+				rend_vec.push_back(render.color_end.r);
+				rend_vec.push_back(render.color_end.g);
+				rend_vec.push_back(render.color_end.b);
+				rend_vec.push_back(render.color_end.a);
+
+				rend_vec.push_back(render.size_start);
+				rend_vec.push_back(render.size_end);
+			}
+		}
+	};
+
+	NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(LiteParticles2DType::Compute,
+		age_delta,
+
+		force_vec,
+
+		turbulence,
+		turbulence_noise_scale,
+		turbulence_individuality,
+		turbulence_time_scale,
+
+		dampening
+	)
+
+	NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(LiteParticles2DType::Render,
+		color_start,
+		color_end,
+
+		size_start,
+		size_end
+	)
+
+	NLOHMANN_DEFINE_TYPE_NON_INTRUSIVE(LiteParticles2DType, compute, render)
+
+} // MM::OpenGL
+

framework/opengl_renderer/src/mm/opengl/lite_particles2d_type_loader.cpp

@@ -0,0 +1,39 @@
+#include "./lite_particles2d_type_loader.hpp"
+
+#include <mm/services/filesystem.hpp>
+
+#include <mm/logger.hpp>
+
+namespace MM::OpenGL {
+
+std::shared_ptr<LiteParticles2DType> LiteParticles2DTypeLoaderJson::load(const nlohmann::json& j) const {
+	auto new_type = std::make_shared<LiteParticles2DType>();
+
+	try {
+		*new_type = j;
+	} catch (...) {
+		SPDLOG_ERROR("failed parsing particle type json:\n{}", j.dump(2));
+		return nullptr;
+	}
+
+	return new_type;
+}
+
+std::shared_ptr<LiteParticles2DType> LiteParticles2DTypeLoaderFile::load(MM::Engine& engine, const std::string& path) const {
+	auto* fs = engine.tryService<MM::Services::FilesystemService>();
+	if (fs == nullptr) {
+		// TODO: error
+		return nullptr;
+	}
+
+	auto new_particle = LiteParticles2DTypeLoaderJson{}.load(fs->readJson(path.c_str()));
+
+	if (!new_particle) {
+		SPDLOG_ERROR("particle type file: '{}'", path);
+	}
+
+	return new_particle;
+}
+
+} // MM::OpenGL
+

framework/opengl_renderer/src/mm/opengl/lite_particles2d_type_loader.hpp

@@ -0,0 +1,18 @@
+#pragma once
+
+#include "./lite_particles2d_type.hpp"
+
+#include <mm/engine_fwd.hpp>
+
+namespace MM::OpenGL {
+
+struct LiteParticles2DTypeLoaderJson final {
+	std::shared_ptr<LiteParticles2DType> load(const nlohmann::json& j) const;
+};
+
+struct LiteParticles2DTypeLoaderFile final {
+	std::shared_ptr<LiteParticles2DType> load(MM::Engine& engine, const std::string& path) const;
+};
+
+} // MM::OpenGL
+

framework/opengl_renderer/src/mm/opengl/render_tasks/lite_particles2d.cpp

@@ -0,0 +1,779 @@
+#include "./lite_particles2d.hpp"
+
+#include <mm/opengl/shader.hpp>
+#include <mm/opengl/shader_builder.hpp>
+#include <mm/opengl/buffer.hpp>
+#include <mm/opengl/instance_buffer.hpp>
+#include <mm/opengl/vertex_array_object.hpp>
+
+#include <mm/fs_const_archiver.hpp>
+
+#include <mm/services/scene_service_interface.hpp>
+#include <entt/entity/registry.hpp>
+#include <mm/components/time_delta.hpp>
+#include <mm/opengl/camera_3d.hpp>
+
+#include "../components/lite_particles2d.hpp"
+
+#include <mm/resource_manager.hpp>
+#include "../lite_particles2d_type.hpp"
+#include <mm/opengl/texture.hpp>
+#include <mm/opengl/texture_loader.hpp>
+
+#include <glm/common.hpp>
+
+#include <tracy/Tracy.hpp>
+#ifndef MM_OPENGL_3_GLES
+	#include <tracy/TracyOpenGL.hpp>
+#else
+	#define TracyGpuContext
+	#define TracyGpuCollect
+	#define TracyGpuZone(...)
+#endif
+
+#include <mm/logger.hpp>
+
+#include <vector>
+
+namespace MM::OpenGL::RenderTasks {
+
+// this was glsl code
+// TODO: refactor this
+// packing helper
+static uint16_t pack_float_16bit(const float a, const float pack_mult) {
+	uint32_t a_bits = uint32_t(abs(a*pack_mult));
+	return (a_bits & 0x7fffu) | (uint16_t(a>=0.0 ? 0u : 1u) << 15u);
+}
+
+const float pack_vel_multiplier = 1000.0;
+
+static float pack_vel(const glm::vec2 vel) {
+	// ez just mult and save as shorts
+	return glm::uintBitsToFloat(
+		(pack_float_16bit(vel.x, pack_vel_multiplier) << 16u)
+		| pack_float_16bit(vel.y, pack_vel_multiplier)
+	);
+}
+
+const float pack_age_multiplier = 10000.0;
+
+static float pack_age_type(const float age, const uint16_t type) {
+	return glm::uintBitsToFloat((pack_float_16bit(age, pack_age_multiplier) << 16u) | (type & 0xffffu));
+}
+
+LiteParticles2D::LiteParticles2D(Engine& engine) {
+	_particles_0_buffers[0] = std::make_unique<InstanceBuffer<glm::vec4>>();
+	_particles_0_buffers[1] = std::make_unique<InstanceBuffer<glm::vec4>>();
+
+	resetBuffers();
+
+	_tf_vao[0] = std::make_unique<VertexArrayObject>();
+	_tf_vao[1] = std::make_unique<VertexArrayObject>();
+
+	auto setup_tf_vao = [this](size_t i) {
+		_tf_vao[i]->bind();
+		_particles_0_buffers[i]->bind();
+		glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, 0);
+		_particles_0_buffers[i]->unbind();
+
+		glEnableVertexAttribArray(0);
+
+		_tf_vao[i]->unbind();
+	};
+
+	setup_tf_vao(0);
+	setup_tf_vao(1);
+
+
+	// rendering
+
+	_render_vao[0] = std::make_unique<VertexArrayObject>();
+	_render_vao[1] = std::make_unique<VertexArrayObject>();
+
+	auto setup_rend_vao = [this](size_t i) {
+		size_t next_index = i == 0 ? 1 : 0;
+
+		_render_vao[i]->bind();
+		// bc we computed into the other one 0->1
+		_particles_0_buffers[next_index]->bind();
+		glVertexAttribPointer(0, 4, GL_FLOAT, GL_FALSE, 0, 0);
+		_particles_0_buffers[next_index]->unbind();
+
+		glEnableVertexAttribArray(0);
+
+		_render_vao[i]->unbind();
+	};
+
+	setup_rend_vao(0);
+	setup_rend_vao(1);
+
+	resetTypeBuffers();
+
+	setupShaderFiles();
+
+	_tf_shader = ShaderBuilder::start()
+		.addStageVertexF(engine, vertexPathTF)
+		.addTransformFeedbackVarying("_out_0")
+		.addStageFragmentF(engine, fragmentPathTF) // empty stage
+		.finish();
+	assert(static_cast<bool>(_tf_shader));
+
+	_points_shader = ShaderBuilder::start()
+		.addStageVertexF(engine, vertexPathPoints)
+		.addStageFragmentF(engine, fragmentPathPoints)
+		.finish();
+	assert(static_cast<bool>(_points_shader));
+
+	_last_time = clock::now();
+}
+
+LiteParticles2D::~LiteParticles2D(void) {
+}
+
+void LiteParticles2D::uploadParticles(Services::OpenGLRenderer&, Scene& scene) {
+	ZoneScopedN("MM::OpenGL::RenderTasks::LiteParticles2D::uploadParticles");
+
+	if (!scene.ctx().contains<Components::LiteParticles2DUploadQueue>()) {
+		// TODO: warn?
+		return; // nothing to upload
+	}
+
+	auto& queue = scene.ctx().at<Components::LiteParticles2DUploadQueue>();
+
+	while (!queue.queue.empty()) {
+		// get range
+		auto range_size = queue.queue.size();
+		size_t range_first = _particle_buffer_next_index;
+		if (_particle_buffer_next_index + (range_size - 1) >= _particle_buffer_size) { // wrap
+			range_size = _particle_buffer_size - range_first;
+		}
+
+		//std::cerr << "s:" << range_size << " f:" << range_first << "\n";
+
+		//assert(range_first <= range_last);
+		assert(range_size >= 1);
+
+		size_t curr_buff_index = first_particles_buffer ? 0 : 1;
+
+#ifdef MM_OPENGL_3_GLES
+		// i think invalidating the whole buffer, instead of only the range results in undefined behaviour, but webgl wont let me otherwise and it seems to work
+		const auto gl_access = GL_MAP_WRITE_BIT | GL_MAP_INVALIDATE_BUFFER_BIT;
+#else
+		// turns out, amd desktop opengl drivers dont like invalidate buffer (everyone else seems to be ok)
+		const auto gl_access = GL_MAP_WRITE_BIT;
+#endif
+
+		auto* data_0 = _particles_0_buffers[curr_buff_index]->mapRange(range_first, range_size, gl_access);
+
+		for (size_t i = 0; i < range_size; i++) {
+			auto& p = queue.queue.front();
+
+			uint16_t type = 0u;
+			if (_type_map.count(p.type_id)) {
+				type = _type_map.at(p.type_id);
+			} else {
+				SPDLOG_ERROR("unknown type {}, defaulting to zero.", p.type_id);
+			}
+
+			data_0[i] = glm::vec4(
+				p.pos.x, p.pos.y,
+				pack_vel(p.vel),
+				pack_age_type(p.age, type)
+			);
+
+			queue.queue.pop();
+		}
+
+		_particles_0_buffers[curr_buff_index]->unmap();
+
+		_particle_buffer_next_index = (range_first + range_size) % (_particle_buffer_size);
+	}
+}
+
+void LiteParticles2D::computeParticles(Services::OpenGLRenderer&, Scene& scene) {
+	ZoneScopedN("MM::OpenGL::RenderTasks::LiteParticles2D::computeParticles");
+	using namespace entt::literals;
+	_tf_shader->bind();
+
+	{ // time
+		auto newNow = clock::now();
+		std::chrono::duration<double, std::ratio<1, 1>> deltaTime = newNow - _last_time;
+		_last_time = newNow;
+
+		float time_delta = deltaTime.count() * scene.ctx().at<MM::Components::TimeDelta>().deltaFactor;
+		_time += time_delta;
+		_tf_shader->setUniform1f("_time_delta", time_delta);
+		_tf_shader->setUniform1f("_time", _time);
+	}
+
+	auto& rm_t = MM::ResourceManager<Texture>::ref();
+	rm_t.get("MM::LiteParticles2DTypes::Compute"_hs)->bind(0);
+
+	//_tf_shader->setUniform3f("_env_vec", env_vec * env_force);
+	//_tf_shader->setUniform1f("_noise_force", noise_force);
+	//_tf_shader->setUniform1f("_dampening", dampening);
+
+	const size_t curr_index = first_particles_buffer ? 0 : 1;
+	const size_t next_index = first_particles_buffer ? 1 : 0;
+
+	// bind in particles
+	_tf_vao[curr_index]->bind();
+
+	// bind out particles
+	// the order is the same as given to the ShaderBuilder
+	_particles_0_buffers[next_index]->bindBase(0);
+
+	glEnable(GL_RASTERIZER_DISCARD); // compute only rn
+
+	glBeginTransformFeedback(GL_POINTS);
+	glDrawArrays(GL_POINTS, 0, _particle_buffer_size);
+	glEndTransformFeedback();
+
+	glDisable(GL_RASTERIZER_DISCARD);
+
+	// TODO: move this
+	glBindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 0, 0);
+	//glBindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 1, 0);
+
+	_tf_vao[curr_index]->unbind();
+	_tf_shader->unbind();
+
+	// TODO: do i need this??
+	glFlush();
+
+	first_particles_buffer = !first_particles_buffer;
+}
+
+void LiteParticles2D::renderParticles(Services::OpenGLRenderer& rs, Scene& scene) {
+	using namespace entt::literals;
+	ZoneScopedN("MM::OpenGL::RenderTasks::LiteParticles2D::renderParticles");
+
+	if (!scene.ctx().contains<Camera3D>()) {
+		return; // nothing to draw
+	}
+
+	//glDisable(GL_DEPTH_TEST);
+	glDisable(GL_BLEND);
+	glEnable(GL_DEPTH_TEST);
+	glDepthMask(GL_FALSE); // dont write to depth
+	//glEnable(GL_BLEND);
+
+#ifndef MM_OPENGL_3_GLES
+	glEnable(GL_PROGRAM_POINT_SIZE);
+#endif
+
+	rs.targets[target_fbo]->bind(FrameBufferObject::RW);
+
+	_points_shader->bind();
+
+	auto& rm_t = MM::ResourceManager<Texture>::ref();
+	rm_t.get("MM::LiteParticles2DTypes::Render"_hs)->bind(0);
+
+	Camera3D& cam = scene.ctx().at<Camera3D>();
+	_points_shader->setUniformMat4f("_vp", cam.getViewProjection());
+
+	GLint view_port[4];
+	glGetIntegerv(GL_VIEWPORT, view_port);
+
+	// width
+	_points_shader->setUniform1f("_point_size", view_port[2]/cam.horizontalViewPortSize);
+
+	const size_t curr_index = first_particles_buffer; // 0->1 / 1->0 bc compute phase also switches
+	_render_vao[curr_index]->bind();
+
+	glDrawArrays(GL_POINTS, 0, _particle_buffer_size);
+
+	_render_vao[curr_index]->unbind();
+	_points_shader->unbind();
+
+	glDepthMask(GL_TRUE);
+}
+
+void LiteParticles2D::render(Services::OpenGLRenderer& rs, Engine& engine) {
+	ZoneScopedN("MM::OpenGL::RenderTasks::LiteParticles2D::render");
+
+	auto* scene_service = engine.tryService<MM::Services::SceneServiceInterface>();
+	if (scene_service == nullptr) {
+		return;
+	}
+
+	Scene& scene = scene_service->getScene();
+
+	uploadParticles(rs, scene);
+	computeParticles(rs, scene);
+	renderParticles(rs, scene);
+}
+
+void LiteParticles2D::resetBuffers(void) {
+	const auto gl_buffer_type = GL_DYNAMIC_COPY;
+	auto reset_buffer_0 = [this](size_t i) {
+		auto* data = _particles_0_buffers[i]->map(_particle_buffer_size, gl_buffer_type);
+		for (size_t x = 0; x < _particle_buffer_size; x++) {
+			data[x] = glm::vec4{
+				0.f, 0.f, // pos
+				0, // vel (pack, but 0 should mean 0)
+				pack_age_type(2.f, 0)
+			};
+		}
+		_particles_0_buffers[i]->unmap();
+	};
+
+	reset_buffer_0(0);
+	reset_buffer_0(1);
+
+	_particle_buffer_next_index = 0; // only matters if resize
+}
+
+void LiteParticles2D::resetTypeBuffers(void) {
+	using namespace entt::literals;
+
+	// clear
+	_type_map.clear();
+
+	// build data
+	std::vector<float> type_compute_upload_buffer {};
+	std::vector<float> type_render_upload_buffer {};
+
+	// TODO: replace with "default"
+	{ // 0
+		// TODO: propper 0 particle
+		LiteParticles2DType {
+			{
+				0.04f, //age_delta;
+
+				{0.f, 0.f}, //force_vec
+
+				5.f, //turbulence;
+				0.1f, //turbulence_noise_scale;
+				0.01f, //turbulence_individuality;
+				0.5f, //turbulence_time_scale;
+
+				1.0f, //dampening;
+			},
+			{
+				{1.8f, 3.f, 6.f, 1.f}, //color_start;
+				{2.3f, 1.2f, 0.5f, 1.f}, //color_end;
+
+				0.1f, //size_start;
+				0.02f //size_end;
+			}
+		}.upload(type_compute_upload_buffer, type_render_upload_buffer);
+	}
+	// defaults
+	_type_map[0u] = 0u;
+	_type_map[""_hs] = 0u;
+	_type_map["0"_hs] = 0u;
+	_type_map["default"_hs] = 0u;
+
+	auto& rm_lpt = MM::ResourceManager<LiteParticles2DType>::ref();
+	uint16_t curr_idx = 1; // 0 is reserved for now :P
+	rm_lpt.each([this, &curr_idx, &type_compute_upload_buffer, &type_render_upload_buffer](const auto type_id, const auto& res) {
+		_type_map[type_id] = curr_idx++;
+		res->upload(type_compute_upload_buffer, type_render_upload_buffer);
+	});
+	SPDLOG_INFO("have {} LiteParticles2D types.", curr_idx);
+
+	// upload / create textures
+	// HACK: refactor loader
+	auto& rm_t = MM::ResourceManager<Texture>::ref();
+	{ // compute
+		auto r = rm_t.reload<MM::OpenGL::TextureLoaderEmpty>(
+			"MM::LiteParticles2DTypes::Compute",
+			GL_R32F,
+			LiteParticles2DType::Compute::_member_count, curr_idx,
+			GL_RED,
+			GL_FLOAT
+		);
+		assert(r);
+
+		// and re-"create"
+		rm_t.get("MM::LiteParticles2DTypes::Compute"_hs)->bind(0); // hack
+		glTexImage2D(
+			GL_TEXTURE_2D,
+			0,
+			GL_R32F,
+			LiteParticles2DType::Compute::_member_count, curr_idx,
+			0,
+			GL_RED,
+			GL_FLOAT,
+			type_compute_upload_buffer.data()
+		);
+		// just in case
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	}
+
+	{ // render
+		auto r = rm_t.reload<MM::OpenGL::TextureLoaderEmpty>(
+			"MM::LiteParticles2DTypes::Render",
+			GL_R32F,
+			LiteParticles2DType::Render::_member_count, curr_idx,
+			GL_RED,
+			GL_FLOAT
+		);
+		assert(r);
+
+		// and re-"create"
+		rm_t.get("MM::LiteParticles2DTypes::Render"_hs)->bind(0); // hack
+		glTexImage2D(
+			GL_TEXTURE_2D,
+			0,
+			GL_R32F,
+			LiteParticles2DType::Render::_member_count, curr_idx,
+			0,
+			GL_RED,
+			GL_FLOAT,
+			type_render_upload_buffer.data()
+		);
+		// just in case
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
+		glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
+	}
+}
+
+void LiteParticles2D::setupShaderFiles(void) {
+	FS_CONST_MOUNT_FILE(commonPathTF,
+R"(
+
+#include "/shaders/builtin/noise.glsl"
+
+// variants, based on offset, might be faster
+vec2 var_noise22(vec2 x) {
+	return vec2(noise12(x), noise12(x + 13037.0));
+}
+vec2 var_noise23(vec3 x) {
+	return vec2(noise13(x), noise13(x + 13037.0));
+}
+vec2 var_noise24(vec4 x) {
+	return vec2(noise14(x), noise14(x + 13037.0));
+}
+
+// packing helper
+uint pack_float_16bit(in float a, in float pack_mult) {
+	uint a_bits = uint(abs(a*pack_mult));
+
+	return (a_bits & 0x7fffu) | (uint(a>=0.0 ? 0u : 1u) << 15u);
+}
+
+float unpack_float_16bit(in uint a, in float pack_mult) {
+	return (float(a & 0x7fffu) / pack_mult) * ((a >> 15u) != 0u ? -1.0 : 1.0);
+}
+
+const float pack_vel_multiplier = 1000.0;
+
+float pack_vel(in vec2 vel) {
+	return uintBitsToFloat(
+		(pack_float_16bit(vel.x, pack_vel_multiplier) << 16u)
+		| pack_float_16bit(vel.y, pack_vel_multiplier)
+	);
+}
+
+vec2 unpack_vel(in float pack) {
+	uint pack_bits = floatBitsToUint(pack);
+	return vec2(
+		unpack_float_16bit(pack_bits >> 16u, pack_vel_multiplier),
+		unpack_float_16bit(pack_bits & 0xffffu, pack_vel_multiplier)
+	);
+}
+
+const float pack_age_multiplier = 10000.0;
+
+float pack_age_type(in float age, in uint type) {
+	return uintBitsToFloat(
+		(pack_float_16bit(age, pack_age_multiplier) << 16u)
+		| (type & 0xffffu)
+	);
+}
+
+)")
+	FS_CONST_MOUNT_FILE(vertexPathTF,
+GLSL_VERSION_STRING
+R"(
+#ifdef GL_ES
+	precision highp float;
+	precision highp int;
+#endif
+
+#include "./common.glsl"
+
+uniform float _time_delta;
+uniform float _time;
+
+uniform sampler2D _type_buffer;
+
+layout(location = 0) in vec4 _in_0;
+
+out vec4 _out_0;
+
+void set_out(in vec2 pos, in vec2 vel, in float age, in uint type) {
+	_out_0 = vec4(
+		pos.x, pos.y,
+		pack_vel(vel),
+		pack_age_type(age, type)
+	);
+}
+
+void get_in(out vec2 pos, out vec2 vel, out float age, out uint type) {
+	pos = _in_0.xy;
+	vel = unpack_vel(_in_0.z);
+
+	uint age_type_bits = floatBitsToUint(_in_0.w);
+	age = unpack_float_16bit(age_type_bits >> 16u, pack_age_multiplier);
+	type = age_type_bits & 0xffffu;
+}
+
+struct sim_config_type {
+	highp float age_delta;
+
+	//highp float gravity;
+	vec2 force_vec;
+
+	highp float turbulence;
+	highp float turbulence_noise_scale;
+	highp float turbulence_individuality;
+	highp float turbulence_time_scale;
+
+	highp float dampening;
+};
+
+vec2 fetch_vec2(in uint offset, in uint type) {
+	return vec2(
+		texelFetch(_type_buffer, ivec2(offset+0u, type), 0).r,
+		texelFetch(_type_buffer, ivec2(offset+1u, type), 0).r
+	);
+}
+
+sim_config_type fetch_type_config(uint type) {
+	return sim_config_type(
+		texelFetch(_type_buffer, ivec2(0, type), 0).r,
+		fetch_vec2(1u, type),
+		texelFetch(_type_buffer, ivec2(3, type), 0).r,
+		texelFetch(_type_buffer, ivec2(4, type), 0).r,
+		texelFetch(_type_buffer, ivec2(5, type), 0).r,
+		texelFetch(_type_buffer, ivec2(6, type), 0).r,
+		texelFetch(_type_buffer, ivec2(7, type), 0).r
+	);
+}
+
+vec2 calc_turbulence_vec(
+	in vec2 pos,
+	in float turbulence,
+	in float turbulence_noise_scale,
+	in float turbulence_individuality,
+	in float turbulence_time_scale
+) {
+	vec2 turbulence_vec =
+		(
+			noise24(vec4(
+				pos * turbulence_noise_scale,
+				float(gl_VertexID & 0x0fff) * turbulence_individuality,
+				_time * turbulence_time_scale
+			))
+			- vec2(0.5)
+		)
+		* 2.0
+		* turbulence
+	;
+
+	return turbulence_vec;
+}
+
+void calc_particle_sim(
+// inout (particle mem)
+	inout vec2 pos,
+	inout vec2 vel,
+
+	inout float age,
+	inout uint type,
+
+// type specific config
+	in sim_config_type conf
+) {
+	vec2 turbulence_vec = calc_turbulence_vec(
+		pos,
+		conf.turbulence,
+		conf.turbulence_noise_scale,
+		conf.turbulence_individuality,
+		conf.turbulence_time_scale
+	);
+
+	vel = (vel + (
+		turbulence_vec +
+		//vec2(0.0, -10.0) * conf.gravity
+		conf.force_vec
+	) * _time_delta);
+
+	// TODO: this does not behave correctly
+	// TODO: experiment with formula
+	vel = mix(vel, vec2(0.0), conf.dampening * _time_delta);
+
+	pos = pos + (vel * _time_delta);
+
+	age = min(age + (conf.age_delta * _time_delta), 2.0);
+}
+
+void main() {
+	vec2 pos;
+	vec2 vel;
+	float age;
+	uint type;
+	get_in(pos, vel, age, type);
+
+	sim_config_type conf = fetch_type_config(type);
+
+	calc_particle_sim(
+		pos,
+		vel,
+		age,
+		type,
+
+		conf
+	);
+
+	set_out(pos, vel, age, type);
+})")
+
+	FS_CONST_MOUNT_FILE(fragmentPathTF,
+GLSL_VERSION_STRING
+R"(
+#ifdef GL_ES
+	precision mediump float;
+#endif
+
+// i am never executed
+
+out vec4 _out_color;
+
+void main() {
+	_out_color = vec4(1.0);
+})")
+
+	FS_CONST_MOUNT_FILE(vertexPathPoints,
+GLSL_VERSION_STRING
+R"(
+#ifdef GL_ES
+	precision highp float;
+	precision highp int;
+#endif
+
+#include "./common.glsl"
+
+uniform mat4 _vp;
+uniform float _point_size;
+
+uniform sampler2D _type_buffer;
+
+layout(location = 0) in vec4 _in_0;
+
+void get_in(out vec2 pos, out vec2 vel, out float age, out uint type) {
+	pos = _in_0.xy;
+	vel = unpack_vel(_in_0.z);
+
+	uint age_type_bits = floatBitsToUint(_in_0.w);
+	age = unpack_float_16bit(age_type_bits >> 16u, pack_age_multiplier);
+	type = age_type_bits & 0xffffu;
+}
+
+out vec4 _frag_color;
+flat out int _vertex_id;
+
+struct config_type {
+	highp vec4 color_start;
+	highp vec4 color_end;
+
+	highp float size_start;
+	highp float size_end;
+};
+
+vec4 fetch_vec4(in uint offset, in uint type) {
+	return vec4(
+		texelFetch(_type_buffer, ivec2(offset+0u, type), 0).r,
+		texelFetch(_type_buffer, ivec2(offset+1u, type), 0).r,
+		texelFetch(_type_buffer, ivec2(offset+2u, type), 0).r,
+		texelFetch(_type_buffer, ivec2(offset+3u, type), 0).r
+	);
+}
+
+config_type fetch_config_type(uint type) {
+	return config_type(
+		fetch_vec4(0u, type),
+		fetch_vec4(4u, type),
+		texelFetch(_type_buffer, ivec2(8, type), 0).r,
+		texelFetch(_type_buffer, ivec2(9, type), 0).r
+	);
+}
+
+void main() {
+	vec2 in_pos;
+	vec2 in_vel;
+
+	float in_age;
+	uint in_type;
+
+	get_in(in_pos, in_vel, in_age, in_type);
+
+	// skip dead
+	if (in_age > 1.0) {
+		_frag_color = vec4(1.0, 0.0, 1.0, 0.0); // so it does not get rendered (alpha)
+		gl_Position.z = 100000000000.0; // clip (does not allways work <.<)
+		// gl_PointSize = 0.0; // ub
+		return;
+	}
+
+	config_type conf = fetch_config_type(in_type);
+
+	//_frag_color = mix(conf.color_start, conf.color_end, in_age);
+	_frag_color = mix(conf.color_start, conf.color_end, smoothstep(0.0, 1.0, in_age));
+
+	gl_Position = _vp * vec4(in_pos, 0.0, 1.0);
+
+	// TODO: fix before merge
+	gl_Position.z = -1.0; // hack for ortho ??
+
+	gl_PointSize = max(mix(conf.size_start, conf.size_end, in_age) * _point_size, 1.0);
+
+	_vertex_id = gl_VertexID;
+})")
+
+	FS_CONST_MOUNT_FILE(fragmentPathPoints,
+GLSL_VERSION_STRING
+R"(
+#ifdef GL_ES
+	precision mediump float;
+#endif
+
+in vec4 _frag_color;
+flat in int _vertex_id;
+
+out vec4 _out_color;
+
+bool should_discard(vec2 screen_pos, float alpha) {
+	const int dither[8 * 8] = int[8 * 8](
+		 0, 32,  8, 40,  2, 34, 10, 42,
+		48, 16, 56, 24, 50, 18, 58, 26,
+		12, 44,  4, 36, 14, 46,  6, 38,
+		60, 28, 52, 20, 62, 30, 54, 22,
+		 3, 35, 11, 43,  1, 33,  9, 41,
+		51, 19, 59, 27, 49, 17, 57, 25,
+		15, 47,  7, 39, 13, 45,  5, 37,
+		63, 31, 55, 23, 61, 29, 53, 21
+	);
+
+	int mat_value = dither[int(screen_pos.x)%8 + 8 * (int(screen_pos.y)%8)];
+	float n_mat_value = float(mat_value) * (1.0/64.0);
+
+	return n_mat_value < 1.0 - alpha;
+}
+
+void main() {
+	if (should_discard(vec2(gl_FragCoord.x + float(_vertex_id%8), gl_FragCoord.y + float(_vertex_id%7)), _frag_color.a)) {
+		discard;
+	}
+
+	_out_color = vec4(_frag_color.rgb, 1.0);
+})")
+
+}
+
+} // MM::OpenGL::RenderTasks
+

framework/opengl_renderer/src/mm/opengl/render_tasks/lite_particles2d.hpp

@@ -0,0 +1,84 @@
+#pragma once
+
+#include <mm/opengl/render_task.hpp>
+#include <mm/services/opengl_renderer.hpp>
+
+#include <glm/fwd.hpp>
+
+// TODO: make the renderer provide a time delta
+#include <chrono>
+#include <string>
+#include <unordered_map>
+
+// fwd
+namespace MM::OpenGL {
+	class Shader;
+	class Buffer;
+	class VertexArrayObject;
+
+	template<typename TInstance>
+	class InstanceBuffer;
+}
+
+namespace MM::OpenGL::RenderTasks {
+
+	class LiteParticles2D : public RenderTask {
+		private:
+			std::shared_ptr<Shader> _tf_shader;
+			std::shared_ptr<Shader> _points_shader;
+
+			std::unordered_map<uint32_t, uint16_t> _type_map {}; // maps id to "index" in type texture
+
+			// double buffered
+			bool first_particles_buffer {true};
+			std::unique_ptr<VertexArrayObject> _tf_vao[2];
+			std::unique_ptr<VertexArrayObject> _render_vao[2];
+
+			// vec2 pos (2 floats)
+			// half vec2 vel (1 float)
+			// fixedpoint age + uint16 type (1 float)
+			std::unique_ptr<MM::OpenGL::InstanceBuffer<glm::vec4>> _particles_0_buffers[2];
+
+			uint32_t _particle_buffer_size {10'000};
+			size_t _particle_buffer_next_index {0};
+
+			using clock = std::chrono::high_resolution_clock;
+			std::chrono::time_point<clock> _last_time;
+			float _time {0};
+
+		public:
+			//glm::vec3 env_vec{0, 1, 0};
+			//float env_force{0.3};
+			//float noise_force{0.5};
+			//float dampening{0.99};
+
+			LiteParticles2D(Engine& engine);
+			~LiteParticles2D(void);
+
+			const char* name(void) override { return "LiteParticles2D"; }
+
+			void uploadParticles(Services::OpenGLRenderer& rs, Scene& scene);
+			void computeParticles(Services::OpenGLRenderer& rs, Scene& scene);
+			void renderParticles(Services::OpenGLRenderer& rs, Scene& scene);
+			void render(Services::OpenGLRenderer& rs, Engine& engine) override;
+
+			void resetBuffers(void);
+			void resetTypeBuffers(void);
+
+		public:
+			const char* commonPathTF {"shader/lite_particles2d/common.glsl"};
+
+			const char* vertexPathTF {"shader/lite_particles2d/tf_vert.glsl"};
+			const char* fragmentPathTF {"shader/lite_particles2d/tf_frag.glsl"}; // "empty" bc of webgl (es)
+
+			const char* vertexPathPoints {"shader/lite_particles2d/point_vert.glsl"};
+			const char* fragmentPathPoints {"shader/lite_particles2d/point_frag.glsl"};
+
+			std::string target_fbo {"display"};
+
+		private:
+			void setupShaderFiles(void);
+	};
+
+} // MM::OpenGL::RenderTasks
+