Transforms

Haunted Library | Collab Alex Braun X MChahin by Mohamed Chahin

引言

上一节我们探讨了时间步长和一些时间问题，今天我们来加入 Transform 变换。

我们的下一步是考虑如何将对象放置在我们世界的不同地方。Transform 变换就像一个模型矩阵，本质上它就像一个世界矩阵，描述了位置、旋转和缩放变换。

大多数游戏引擎使用 ECS 架构作为组件系统，许多组件组合在一起形成一个游戏对象。很显然 Transfrom 实际上是一个组件，它是存储数据的地方。

Submit函数修改

修改 Infinite/Renderer/Renderer.h，输入参数加入 transform 矩阵：

@@ -13,7 +13,7 @@ namespace Infinite {
		static void BeginScene(OrthographicCamera& camera);
		static void EndScene();

-		static void Submit(const std::shared_ptr<Shader>& shader, const std::shared_ptr<VertexArray>& vertexArray);
+		static void Submit(const std::shared_ptr<Shader>& shader, const std::shared_ptr<VertexArray>& vertexArray, const glm::mat4& transform = glm::mat4(1.0f));


		inline static RendererAPI::API GetAPI() { return RendererAPI::GetAPI(); }

Renderer.cpp 也稍作修改：

	{
	}

-	void Renderer::Submit(const std::shared_ptr<Shader>& shader, const std::shared_ptr<VertexArray>& vertexArray)
+	void Renderer::Submit(const std::shared_ptr<Shader>& shader, const std::shared_ptr<VertexArray>& vertexArray, const glm::mat4& transform)
	{
		shader->Bind();
		shader->UploadUniformMat4("u_ViewProjection", s_SceneData->ViewProjectionMatrix);
+		shader->UploadUniformMat4("u_Transform", transform);

		vertexArray->Bind();
		RenderCommand::DrawIndexed(vertexArray);

Shader修改

@@ -2,6 +2,8 @@

#include "../imgui/imgui.h"

+#include <glm/gtc/matrix_transform.hpp>

class ExampleLayer : public Infinite::Layer
{
public:
@@ -36,10 +38,10 @@ class ExampleLayer : public Infinite::Layer
		m_SquareVertexArray.reset(Infinite::VertexArray::Create());

		float squareVertices[3 * 4] = {
-			-0.75f, -0.75f, 0.0f,
-			0.75f, -0.75f, 0.0f,
-			0.75f,  0.75f, 0.0f,
-			-0.75f,  0.75f, 0.0f
+			-0.5f, -0.5f, 0.0f,
+			 0.5f, -0.5f, 0.0f,
+			 0.5f,  0.5f, 0.0f,
+			-0.5f,  0.5f, 0.0f
		};
		std::shared_ptr<Infinite::VertexBuffer> squareVertexBuffer;
		squareVertexBuffer.reset(Infinite::VertexBuffer::Create(squareVertices, sizeof(squareVertices)));
@@ -62,6 +64,7 @@ class ExampleLayer : public Infinite::Layer
			layout(location = 1) in vec4 a_Color;
			uniform mat4 u_ViewProjection;
+			uniform mat4 u_Transform;
			out vec3 v_Position;
			out vec4 v_Color;
@@ -70,7 +73,7 @@ class ExampleLayer : public Infinite::Layer
			{
				v_Position = a_Position;
				v_Color = a_Color;
-				gl_Position = u_ViewProjection * vec4(a_Position, 1.0);	
+				gl_Position = u_ViewProjection * u_Transform * vec4(a_Position, 1.0);	
			}
		)";

@@ -99,12 +102,13 @@ class ExampleLayer : public Infinite::Layer
			layout(location = 0) in vec3 a_Position;
			uniform mat4 u_ViewProjection;
+			uniform mat4 u_Transform;
			out vec3 v_Position;
			void main()
			{
				v_Position = a_Position;
-				gl_Position = u_ViewProjection * vec4(a_Position, 1.0);	
+				gl_Position = u_ViewProjection * u_Transform * vec4(a_Position, 1.0);	
			}
		)";

@@ -131,12 +135,12 @@ class ExampleLayer : public Infinite::Layer
			m_CameraPosition.x -= m_CameraMoveSpeed * ts;
		else if (Infinite::Input::IsKeyPressed(IFN_KEY_RIGHT))
			m_CameraPosition.x += m_CameraMoveSpeed * ts;
		

		if (Infinite::Input::IsKeyPressed(IFN_KEY_DOWN))
			m_CameraPosition.y -= m_CameraMoveSpeed * ts;
		else if (Infinite::Input::IsKeyPressed(IFN_KEY_UP))
			m_CameraPosition.y += m_CameraMoveSpeed * ts;
		

		if (Infinite::Input::IsKeyPressed(IFN_KEY_A))
			m_CameraRotation += m_CameraRotationSpeed * ts;
		else if (Infinite::Input::IsKeyPressed(IFN_KEY_D))
@@ -151,7 +155,20 @@ class ExampleLayer : public Infinite::Layer

		Infinite::Renderer::BeginScene(m_Camera);

-		Infinite::Renderer::Submit(m_BlueShader, m_SquareVertexArray);
+		glm::mat4 scale = glm::scale(glm::mat4(1.0f), glm::vec3(0.1f));
+
+		for (int y = 0; y < 20; y++)
+		{
+			for (int x = 0; x < 20; x++)
+			{
+				glm::vec3 pos(x * 0.11f, y * 0.11f, 0.0f);
+				glm::mat4 transform = glm::translate(glm::mat4(1.0f), pos) * scale;
+				Infinite::Renderer::Submit(m_BlueShader, m_SquareVertexArray, transform);
+			}
+		}



		Infinite::Renderer::Submit(m_Shader, m_VertexArray);

		Infinite::Renderer::EndScene();
@@ -183,7 +200,7 @@ class ExampleLayer : public Infinite::Layer
	glm::vec3 m_CameraPosition;
	float m_CameraRotation = 0.0f;
	float m_CameraMoveSpeed = 5.0f;
-	float m_CameraRotationSpeed = 180.0f;
+	float m_CameraRotationSpeed = 3.0f;
};

class Sandbox : public Infinite::Application {

调试