particles! Weird EBO stuff

CMakeLists.txt

@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.25)
-project(gpu-particles VERSION 0.0.14)
+project(gpu-particles VERSION 0.0.15)
 
 option(ENABLE_ADDRSAN "Enable the address sanitizer" OFF)
 option(ENABLE_UBSAN "Enable the ub sanitizer" OFF)

include/shaders/particle.frag

@@ -4,13 +4,21 @@ const std::string shader_particle_2d_frag = R"("
 #version 300 es
 precision mediump float;
 
-uniform sampler2D tex;
+uniform sampler2D tex1;
+uniform sampler2D tex2;
+
+in float silly;
 
 layout (location = 0) out vec4 FragColor;
 
 void main()
 {
-    FragColor = texture(tex, gl_PointCoord);
+    float x = gl_PointCoord.x;
+    float y = 1.0f - gl_PointCoord.y;
+    if (silly > 0.0f)
+        FragColor = texture(tex1, vec2(x, y));
+    else
+        FragColor = texture(tex2, vec2(x, y));
 }
 
 ")";

include/shaders/particle.vert

@@ -6,6 +6,8 @@ precision mediump float;
 
 layout (location = 0) in vec2 position;
 
+out float silly;
+
 layout (std140) uniform GlobalMatrices
 {
     mat4 projection;
@@ -17,6 +19,10 @@ layout (std140) uniform GlobalMatrices
 
 void main()
 {
+    if (mod(position.x + position.y, 32.0f) >= 16.0f)
+        silly = 1.0f;
+    else
+        silly = 0.0f;
     gl_Position = ovm * vec4(position.x, position.y, 0.0, 1.0);
 }
 

include/vao.h

@@ -21,6 +21,7 @@
 
 #include <memory>
 #include <vbo.h>
+#include <blt/std/hashmap.h>
 #include <blt/std/vector.h>
 
 namespace blt::gfx
@@ -32,7 +33,7 @@ namespace blt::gfx
 		struct vao_vbo_storage_t
 		{
 			std::unique_ptr<unique_vbo_t> vbo;
-			std::optional<std::vector<u32>> attribute_numbers;
+			std::optional<hashset_t<u32>> attribute_numbers;
 
 			[[nodiscard]] bool is_element() const
 			{
@@ -101,7 +102,6 @@ namespace blt::gfx
 			vao_context_t& unbind();
 
 			vao_vbo_context_t attach_vbo(unique_vbo_t&& vbo) const;
-
 		private:
 			[[nodiscard]] bool is_bound() const;
 
@@ -140,6 +140,39 @@ namespace blt::gfx
 
 		detail::vao_context_t bind();
 
+		[[nodiscard]] std::optional<ref<unique_vbo_t>> get_attribute(const u32 attribute) const
+		{
+			for (const auto& vbo_obj : vbo_list)
+			{
+				if (const auto attrs = vbo_obj.attribute_numbers)
+				{
+					if (attrs->contains(attribute))
+						return *vbo_obj.vbo;
+				}
+			}
+			return {};
+		}
+
+		[[nodiscard]] std::optional<ref<unique_vbo_t>> get_buffer_type(const GLuint buffer_type) const
+		{
+			for (const auto& vbo_obj : vbo_list)
+			{
+				if (vbo_obj.vbo->get_buffer_type() == buffer_type)
+					return *vbo_obj.vbo;
+			}
+			return {};
+		}
+
+		[[nodiscard]] std::optional<ref<unique_vbo_t>> get_element() const
+		{
+			for (const auto& vbo_obj : vbo_list)
+			{
+				if (vbo_obj.is_element())
+					return *vbo_obj.vbo;
+			}
+			return {};
+		}
+
 		~unique_vao_t()
 		{
 			if (vaoID)

src/main.cpp

@@ -30,7 +30,7 @@ constexpr blt::size_t PARTICLE_COUNT = 8192;
 blt::gfx::matrix_state_manager global_matrices;
 blt::gfx::resource_manager resources;
 blt::gfx::batch_renderer_2d renderer_2d(resources, global_matrices);
-blt::gfx::first_person_camera camera;
+blt::gfx::first_person_camera_2d camera;
 
 // use types for state that way you are not confused about what is happening?
 
@@ -39,43 +39,80 @@ struct particle_t
 	blt::vec2 position;
 	blt::vec2 velocity;
 	blt::vec2 acceleration;
+	float mass = 10;
+	float unused;
 
 	static particle_t make_particle()
 	{
-		blt::random::random_t random{std::random_device()()};
-		return {blt::vec2{random.get(0.0f, 500.0f), random.get(0.0f, 500.0f)}, blt::vec2{}, blt::vec2{}};
+		static blt::random::random_t random{std::random_device()()};
+		return {blt::vec2{random.get(20.0f, 1880.0f), random.get(20.0f, 1000.0f)}, blt::vec2{}, blt::vec2{}};
 	}
 };
 
-std::optional<blt::gfx::unique_vao_t> particle_vao;
-std::unique_ptr<blt::gfx::shader_t> particle_shader;
+class gpu_particle_renderer
+{
+public:
+	gpu_particle_renderer()
+	{
+		using namespace blt::gfx;
 
-std::vector<blt::u32> alive_particles;
-std::vector<blt::u32> dead_particles;
-std::vector<particle_t> particles;
+		for (blt::size_t i = 0; i < PARTICLE_COUNT; i++)
+		{
+			particles.push_back(particle_t::make_particle());
+			alive_particles.push_back(i);
+		}
+
+		particle_shader = std::unique_ptr<shader_t>(shader_t::make(shader_particle_2d_vert, shader_particle_2d_frag));
+
+		unique_vbo_t particle_vbo(GL_ARRAY_BUFFER);
+		particle_vbo.bind().upload(sizeof(particle_t) * particles.size(), particles.data(), GL_DYNAMIC_DRAW);
+
+		unique_ebo_t alive_particles_ebo;
+		alive_particles_ebo.bind().upload(sizeof(blt::u32) * alive_particles.size(), alive_particles.data(), GL_DYNAMIC_DRAW);
+
+		auto vao_ctx = particle_vao.bind();
+		vao_ctx.attach_vbo(std::move(particle_vbo)).attribute_ptr(0, 2, GL_FLOAT, sizeof(particle_t), 0);
+		vao_ctx.attach_vbo(std::move(alive_particles_ebo));
+		vao_ctx.unbind();
+	}
+
+	void render()
+	{
+		glPointSize(25);
+
+		particle_shader->bind();
+		particle_shader->setInt("tex1", 0);
+		particle_shader->setInt("tex2", 1);
+		particle_vao.bind();
+		// particle_vao.get_element()->get().bind();
+		glActiveTexture(GL_TEXTURE0);
+		resources.get("silly").value()->bind();
+		glActiveTexture(GL_TEXTURE1);
+		resources.get("happy").value()->bind();
+
+		glDrawElements(GL_POINTS, static_cast<int>(alive_particles.size()), GL_UNSIGNED_INT, nullptr);
+	}
+
+private:
+	blt::gfx::unique_vao_t particle_vao;
+	std::unique_ptr<blt::gfx::shader_t> particle_shader;
+
+	std::vector<blt::u32> alive_particles;
+	std::vector<blt::u32> dead_particles;
+	std::vector<particle_t> particles;
+};
+
+std::optional<gpu_particle_renderer> particle_renderer;
 
 void init(const blt::gfx::window_data&)
 {
 	using namespace blt::gfx;
+	resources.setPrefixDirectory("../");
 
-	particle_shader = std::unique_ptr<shader_t>(shader_t::make(shader_particle_2d_vert, shader_particle_2d_frag));
+	resources.enqueue("res/silly.png", "silly");
+	resources.enqueue("res/images_4.jpeg", "happy");
 
-	for (blt::size_t i = 0; i < PARTICLE_COUNT; i++)
-	{
-		particles.push_back(particle_t::make_particle());
-		alive_particles.push_back(i);
-	}
-
-	unique_vbo_t particle_vbo(GL_ARRAY_BUFFER);
-	particle_vbo.bind().upload(sizeof(particle_t) * particles.size(), particles.data(), GL_DYNAMIC_DRAW);
-
-	unique_ebo_t alive_particles_ebo;
-	alive_particles_ebo.bind().upload(sizeof(blt::u32) * alive_particles.size(), alive_particles.data(), GL_DYNAMIC_DRAW);
-
-	particle_vao = unique_vao_t();
-	const auto vao_ctx = particle_vao->bind();
-	vao_ctx.attach_vbo(std::move(particle_vbo)).attribute_ptr(0, 2, GL_FLOAT, sizeof(particle_t), 0);
-	vao_ctx.attach_vbo(std::move(alive_particles_ebo));
+	particle_renderer = gpu_particle_renderer{};
 
 	global_matrices.create_internals();
 	resources.load_resources();
@@ -91,12 +128,13 @@ void update(const blt::gfx::window_data& data)
 	global_matrices.update();
 
 	renderer_2d.render(data.width, data.height);
+
+	particle_renderer->render();
 }
 
 void destroy(const blt::gfx::window_data&)
 {
-	particle_vao.reset();
-	particle_shader.reset();
+	particle_renderer.reset();
 	global_matrices.cleanup();
 	resources.cleanup();
 	renderer_2d.cleanup();

src/vao.cpp

@@ -25,22 +25,16 @@ namespace blt::gfx
 	#define ENSURE_CONTEXT_BOUND BLT_CONTRACT(glfwGetCurrentContext() != nullptr, "Expected active OpenGL context!")
 
 	#if blt_debug_has_flag(BLT_DEBUG_CONTRACTS)
-	GLuint bound_vao_id;
+	GLuint bound_vao_id = 0;
 	#endif
 
 	detail::vao_vbo_context_t& detail::vao_vbo_context_t::attribute_ptr(const int attribute_number, const int coordinate_size, const GLenum type,
 																		const int stride, const long offset)
 	{
-		if (auto& vec = vbo.attribute_numbers)
-		{
-			for (const auto& v : *vec)
-			{
-				if (static_cast<i32>(v) == attribute_number)
-					goto use;
-			}
-			vec->push_back(attribute_number);
-		}
-		use:
+		if (!vbo.attribute_numbers)
+			vbo.attribute_numbers = hashset_t<u32>();
+		if (!vbo.attribute_numbers->contains(attribute_number))
+			vbo.attribute_numbers->insert(attribute_number);
 		glEnableVertexAttribArray(attribute_number);
 		glVertexAttribPointer(attribute_number, coordinate_size, type, GL_FALSE, stride < 0 ? 0 : stride, reinterpret_cast<void*>(offset));
 		attributed = true;
@@ -69,6 +63,7 @@ namespace blt::gfx
 
 	detail::vao_context_t& detail::vao_context_t::unbind() // NOLINT
 	{
+		ENSURE_CONTEXT_BOUND;
 		glBindVertexArray(0);
 		bound_vao_id = 0;
 		return *this;