smallpt: Global Illumination in 99 lines of C++鍾誠 陳鍾誠
This document summarizes Kevin Beason's smallpt, a 99 line path tracer written in C++. It begins with an overview of global illumination and path tracing. It then walks through the key parts of smallpt, including ray and vector classes, sphere intersections, scene description, camera setup, the rendering equation, path tracing algorithm, and functions for diffuse reflection, specular reflection, refraction, and more. The document provides explanations of the algorithms and math concepts used in smallpt.
This document discusses the history and development of computer architecture from early machines like Babbage's Analytical Engine to the modern von Neumann architecture. It then describes the specific architecture of the Hack computer being built, including its instruction memory, data memory divided into areas for general data, screen, and keyboard, and the CPU that fetches and executes instructions. The goal is to build this computer from basic logic gates and chips following the levels of abstraction presented.
The document discusses machine language and its relationship to hardware and software. Machine language can be viewed as a programmer-oriented abstraction of the hardware platform that allows manipulating memory using a processor and registers. It has both binary and symbolic representations. The Hack computer is presented as an example machine with a 16-bit instruction set consisting of A-instructions to set registers and C-instructions to perform arithmetic and logical operations. Examples are provided of coding common programming constructs like conditionals and loops in the Hack machine language.
This document discusses sequential logic and how it differs from combinational logic. Sequential logic operates on both data and a clock signal, allowing it to store state information. It presents a hierarchy of memory elements starting with flip-flops, then binary cells, registers, RAM, and counters. Registers and RAM are built from arrays of flip-flops. Counters store and increment a value over time. All sequential chips use flip-flops and a clock to synchronize state changes.
The document discusses Boolean arithmetic and building basic computing components like adders and arithmetic logic units (ALUs) using logic gates. It introduces binary number representation and addition, as well as representing negative numbers. Half adders and full adders are presented as the basic building blocks for adding bits and numbers. An n-bit adder can add two n-bit numbers by chaining together full adders. The ALU is designed to perform basic arithmetic and logical operations on inputs based on control bits, and is a key component in central processing units. The document provides a high-level overview of representing and performing arithmetic at the digital circuit level.
The document discusses Boolean logic and functions. It introduces Boolean algebra and some basic Boolean functions like AND, OR, and NOT. It explains that every Boolean function can be expressed using only AND, OR, and NOT. The document then discusses implementing Boolean functions using logic gates like NAND gates. It provides an example of building an AND gate from NAND gates. Finally, it discusses a hardware simulator that can be used to test HDL programs implementing Boolean functions and logic gates.
This document discusses Boolean arithmetic and the design of an adder chip. It explains how half adders and full adders can be used to build an n-bit adder to add two binary numbers. The document also introduces the arithmetic logic unit (ALU) and how it can perform operations like addition, subtraction, AND, and OR using control bits and the logic of half and full adders. The ALU is a key component of the central processing unit (CPU) that allows computers to perform arithmetic and logical operations on data.
The document introduces the Nand2Tetris course which builds a modern computer from first principles. It starts with basic logic gates and progresses all the way to a high-level language. The course uses an abstraction-implementation paradigm, with each level providing abstract interfaces for the next. It covers topics like Boolean logic, machine language, assembly language, virtual machine implementation, compilers, and an operating system. The goal is to help students understand how computing systems work "under the hood".