Author: Doug Bowman
Publisher: Addison-Wesley
ISBN: 013339056X
Category : Business & Economics
Languages : en
Pages : 867
Book Description
Here’s what three pioneers in computer graphics and human-computer interaction have to say about this book: “What a tour de force—everything one would want—comprehensive, encyclopedic, and authoritative.” — Jim Foley “At last, a book on this important, emerging area. It will be an indispensable reference for the practitioner, researcher, and student interested in 3D user interfaces.” — Andy van Dam “Finally, the book we need to bridge the dream of 3D graphics with the user-centered reality of interface design. A thoughtful and practical guide for researchers and product developers. Thorough review, great examples.” — Ben Shneiderman As 3D technology becomes available for a wide range of applications, its successful deployment will require well-designed user interfaces (UIs). Specifically, software and hardware developers will need to understand the interaction principles and techniques peculiar to a 3D environment. This understanding, of course, builds on usability experience with 2D UIs. But it also involves new and unique challenges and opportunities. Discussing all relevant aspects of interaction, enhanced by instructive examples and guidelines, 3D User Interfaces comprises a single source for the latest theory and practice of 3D UIs. Many people already have seen 3D UIs in computer-aided design, radiation therapy, surgical simulation, data visualization, and virtual-reality entertainment. The next generation of computer games, mobile devices, and desktop applications also will feature 3D interaction. The authors of this book, each at the forefront of research and development in the young and dynamic field of 3D UIs, show how to produce usable 3D applications that deliver on their enormous promise. Coverage includes: The psychology and human factors of various 3D interaction tasks Different approaches for evaluating 3D UIs Results from empirical studies of 3D interaction techniques Principles for choosing appropriate input and output devices for 3D systems Details and tips on implementing common 3D interaction techniques Guidelines for selecting the most effective interaction techniques for common 3D tasks Case studies of 3D UIs in real-world applications To help you keep pace with this fast-evolving field, the book’s Web site, www.3dui.org, will offer information and links to the latest 3D UI research and applications.
3D User Interfaces
Author: Doug Bowman
Publisher: Addison-Wesley
ISBN: 013339056X
Category : Business & Economics
Languages : en
Pages : 867
Book Description
Here’s what three pioneers in computer graphics and human-computer interaction have to say about this book: “What a tour de force—everything one would want—comprehensive, encyclopedic, and authoritative.” — Jim Foley “At last, a book on this important, emerging area. It will be an indispensable reference for the practitioner, researcher, and student interested in 3D user interfaces.” — Andy van Dam “Finally, the book we need to bridge the dream of 3D graphics with the user-centered reality of interface design. A thoughtful and practical guide for researchers and product developers. Thorough review, great examples.” — Ben Shneiderman As 3D technology becomes available for a wide range of applications, its successful deployment will require well-designed user interfaces (UIs). Specifically, software and hardware developers will need to understand the interaction principles and techniques peculiar to a 3D environment. This understanding, of course, builds on usability experience with 2D UIs. But it also involves new and unique challenges and opportunities. Discussing all relevant aspects of interaction, enhanced by instructive examples and guidelines, 3D User Interfaces comprises a single source for the latest theory and practice of 3D UIs. Many people already have seen 3D UIs in computer-aided design, radiation therapy, surgical simulation, data visualization, and virtual-reality entertainment. The next generation of computer games, mobile devices, and desktop applications also will feature 3D interaction. The authors of this book, each at the forefront of research and development in the young and dynamic field of 3D UIs, show how to produce usable 3D applications that deliver on their enormous promise. Coverage includes: The psychology and human factors of various 3D interaction tasks Different approaches for evaluating 3D UIs Results from empirical studies of 3D interaction techniques Principles for choosing appropriate input and output devices for 3D systems Details and tips on implementing common 3D interaction techniques Guidelines for selecting the most effective interaction techniques for common 3D tasks Case studies of 3D UIs in real-world applications To help you keep pace with this fast-evolving field, the book’s Web site, www.3dui.org, will offer information and links to the latest 3D UI research and applications.
Publisher: Addison-Wesley
ISBN: 013339056X
Category : Business & Economics
Languages : en
Pages : 867
Book Description
Here’s what three pioneers in computer graphics and human-computer interaction have to say about this book: “What a tour de force—everything one would want—comprehensive, encyclopedic, and authoritative.” — Jim Foley “At last, a book on this important, emerging area. It will be an indispensable reference for the practitioner, researcher, and student interested in 3D user interfaces.” — Andy van Dam “Finally, the book we need to bridge the dream of 3D graphics with the user-centered reality of interface design. A thoughtful and practical guide for researchers and product developers. Thorough review, great examples.” — Ben Shneiderman As 3D technology becomes available for a wide range of applications, its successful deployment will require well-designed user interfaces (UIs). Specifically, software and hardware developers will need to understand the interaction principles and techniques peculiar to a 3D environment. This understanding, of course, builds on usability experience with 2D UIs. But it also involves new and unique challenges and opportunities. Discussing all relevant aspects of interaction, enhanced by instructive examples and guidelines, 3D User Interfaces comprises a single source for the latest theory and practice of 3D UIs. Many people already have seen 3D UIs in computer-aided design, radiation therapy, surgical simulation, data visualization, and virtual-reality entertainment. The next generation of computer games, mobile devices, and desktop applications also will feature 3D interaction. The authors of this book, each at the forefront of research and development in the young and dynamic field of 3D UIs, show how to produce usable 3D applications that deliver on their enormous promise. Coverage includes: The psychology and human factors of various 3D interaction tasks Different approaches for evaluating 3D UIs Results from empirical studies of 3D interaction techniques Principles for choosing appropriate input and output devices for 3D systems Details and tips on implementing common 3D interaction techniques Guidelines for selecting the most effective interaction techniques for common 3D tasks Case studies of 3D UIs in real-world applications To help you keep pace with this fast-evolving field, the book’s Web site, www.3dui.org, will offer information and links to the latest 3D UI research and applications.
Interaction Design for 3D User Interfaces
Author: Francisco R. Ortega
Publisher: CRC Press
ISBN: 1482216957
Category : Computers
Languages : en
Pages : 784
Book Description
This book addresses the new interaction modalities that are becoming possible with new devices by looking at user interfaces from an input perspective. It deals with modern input devices and user interaction and design covering in-depth theory, advanced topics for noise reduction using Kalman Filters, a case study, and multiple chapters showing hands-on approaches to relevant technology, including modern devices such as the Leap-Motion, Xbox One Kinect, inertial measurement units, and multi-touch technology. It also discusses theories behind interaction and navigation, past and current techniques, and practical topics about input devices.
Publisher: CRC Press
ISBN: 1482216957
Category : Computers
Languages : en
Pages : 784
Book Description
This book addresses the new interaction modalities that are becoming possible with new devices by looking at user interfaces from an input perspective. It deals with modern input devices and user interaction and design covering in-depth theory, advanced topics for noise reduction using Kalman Filters, a case study, and multiple chapters showing hands-on approaches to relevant technology, including modern devices such as the Leap-Motion, Xbox One Kinect, inertial measurement units, and multi-touch technology. It also discusses theories behind interaction and navigation, past and current techniques, and practical topics about input devices.
Designing Interfaces
Author: Jenifer Tidwell
Publisher: "O'Reilly Media, Inc."
ISBN: 0596008031
Category : Computers
Languages : en
Pages : 352
Book Description
This text offers advice on creating user-friendly interface designs - whether they're delivered on the Web, a CD, or a 'smart' device like a cell phone. It presents solutions to common UI design problems as a collection of patterns - each containing concrete examples, recommendations, and warnings.
Publisher: "O'Reilly Media, Inc."
ISBN: 0596008031
Category : Computers
Languages : en
Pages : 352
Book Description
This text offers advice on creating user-friendly interface designs - whether they're delivered on the Web, a CD, or a 'smart' device like a cell phone. It presents solutions to common UI design problems as a collection of patterns - each containing concrete examples, recommendations, and warnings.
Brave NUI World
Author: Daniel Wigdor
Publisher: Elsevier
ISBN: 0123822327
Category : Computers
Languages : en
Pages : 257
Book Description
Brave NUI World is the first practical guide for designing touch- and gesture-based user interfaces. Written by the team from Microsoft that developed the multi-touch, multi-user Surface® tabletop product, it introduces the reader to natural user interfaces (NUI). It gives readers the necessary tools and information to integrate touch and gesture practices into daily work, presenting scenarios, problem solving, metaphors, and techniques intended to avoid making mistakes. This book considers diverse user needs and context, real world successes and failures, and the future of NUI. It presents thirty scenarios, giving practitioners a multitude of considerations for making informed design decisions and helping to ensure that missteps are never made again. The book will be of value to game designers as well as practitioners, researchers, and students interested in learning about user experience design, user interface design, interaction design, software design, human computer interaction, human factors, information design, and information architecture. - Provides easy-to-apply design guidance for the unique challenge of creating touch- and gesture-based user interfaces - Considers diverse user needs and context, real world successes and failures, and a look into the future of NUI - Presents thirty scenarios, giving practitioners a multitude of considerations for making informed design decisions and helping to ensure that missteps are never made again
Publisher: Elsevier
ISBN: 0123822327
Category : Computers
Languages : en
Pages : 257
Book Description
Brave NUI World is the first practical guide for designing touch- and gesture-based user interfaces. Written by the team from Microsoft that developed the multi-touch, multi-user Surface® tabletop product, it introduces the reader to natural user interfaces (NUI). It gives readers the necessary tools and information to integrate touch and gesture practices into daily work, presenting scenarios, problem solving, metaphors, and techniques intended to avoid making mistakes. This book considers diverse user needs and context, real world successes and failures, and the future of NUI. It presents thirty scenarios, giving practitioners a multitude of considerations for making informed design decisions and helping to ensure that missteps are never made again. The book will be of value to game designers as well as practitioners, researchers, and students interested in learning about user experience design, user interface design, interaction design, software design, human computer interaction, human factors, information design, and information architecture. - Provides easy-to-apply design guidance for the unique challenge of creating touch- and gesture-based user interfaces - Considers diverse user needs and context, real world successes and failures, and a look into the future of NUI - Presents thirty scenarios, giving practitioners a multitude of considerations for making informed design decisions and helping to ensure that missteps are never made again
Designing Mobile Interfaces
Author: Steven Hoober
Publisher: "O'Reilly Media, Inc."
ISBN: 1449321321
Category : Computers
Languages : en
Pages : 584
Book Description
With hundreds of thousands of mobile applications available today, your app has to capture users immediately. This book provides practical techniques to help you catch—and keep—their attention. You’ll learn core principles for designing effective user interfaces, along with a set of common patterns for interaction design on all types of mobile devices. Mobile design specialists Steven Hoober and Eric Berkman have collected and researched 76 best practices for everything from composing pages and displaying information to the use of screens, lights, and sensors. Each pattern includes a discussion of the design problem and solution, along with variations, interaction and presentation details, and antipatterns. Compose pages so that information is easy to locate and manipulate Provide labels and visual cues appropriate for your app’s users Use information control widgets to help users quickly access details Take advantage of gestures and other sensors Apply specialized methods to prevent errors and the loss of user-entered data Enable users to easily make selections, enter text, and manipulate controls Use screens, lights, haptics, and sounds to communicate your message and increase user satisfaction "Designing Mobile Interfaces is another stellar addition to O’Reilly’s essential interface books. Every mobile designer will want to have this thorough book on their shelf for reference." —Dan Saffer, Author of Designing Gestural Interfaces
Publisher: "O'Reilly Media, Inc."
ISBN: 1449321321
Category : Computers
Languages : en
Pages : 584
Book Description
With hundreds of thousands of mobile applications available today, your app has to capture users immediately. This book provides practical techniques to help you catch—and keep—their attention. You’ll learn core principles for designing effective user interfaces, along with a set of common patterns for interaction design on all types of mobile devices. Mobile design specialists Steven Hoober and Eric Berkman have collected and researched 76 best practices for everything from composing pages and displaying information to the use of screens, lights, and sensors. Each pattern includes a discussion of the design problem and solution, along with variations, interaction and presentation details, and antipatterns. Compose pages so that information is easy to locate and manipulate Provide labels and visual cues appropriate for your app’s users Use information control widgets to help users quickly access details Take advantage of gestures and other sensors Apply specialized methods to prevent errors and the loss of user-entered data Enable users to easily make selections, enter text, and manipulate controls Use screens, lights, haptics, and sounds to communicate your message and increase user satisfaction "Designing Mobile Interfaces is another stellar addition to O’Reilly’s essential interface books. Every mobile designer will want to have this thorough book on their shelf for reference." —Dan Saffer, Author of Designing Gestural Interfaces
Make It So
Author: Nathan Shedroff
Publisher: Rosenfeld Media
ISBN: 1933820764
Category : Computers
Languages : en
Pages : 369
Book Description
Many designers enjoy the interfaces seen in science fiction films and television shows. Freed from the rigorous constraints of designing for real users, sci-fi production designers develop blue-sky interfaces that are inspiring, humorous, and even instructive. By carefully studying these “outsider” user interfaces, designers can derive lessons that make their real-world designs more cutting edge and successful.
Publisher: Rosenfeld Media
ISBN: 1933820764
Category : Computers
Languages : en
Pages : 369
Book Description
Many designers enjoy the interfaces seen in science fiction films and television shows. Freed from the rigorous constraints of designing for real users, sci-fi production designers develop blue-sky interfaces that are inspiring, humorous, and even instructive. By carefully studying these “outsider” user interfaces, designers can derive lessons that make their real-world designs more cutting edge and successful.
User Interface Design for Programmers
Author: Avram Joel Spolsky
Publisher: Apress
ISBN: 1430208570
Category : Computers
Languages : en
Pages : 152
Book Description
Most programmers' fear of user interface (UI) programming comes from their fear of doing UI design. They think that UI design is like graphic design—the mysterious process by which creative, latte-drinking, all-black-wearing people produce cool-looking, artistic pieces. Most programmers see themselves as analytic, logical thinkers instead—strong at reasoning, weak on artistic judgment, and incapable of doing UI design. In this brilliantly readable book, author Joel Spolsky proposes simple, logical rules that can be applied without any artistic talent to improve any user interface, from traditional GUI applications to websites to consumer electronics. Spolsky's primary axiom, the importance of bringing the program model in line with the user model, is both rational and simple. In a fun and entertaining way, Spolky makes user interface design easy for programmers to grasp. After reading User Interface Design for Programmers, you'll know how to design interfaces with the user in mind. You'll learn the important principles that underlie all good UI design, and you'll learn how to perform usability testing that works.
Publisher: Apress
ISBN: 1430208570
Category : Computers
Languages : en
Pages : 152
Book Description
Most programmers' fear of user interface (UI) programming comes from their fear of doing UI design. They think that UI design is like graphic design—the mysterious process by which creative, latte-drinking, all-black-wearing people produce cool-looking, artistic pieces. Most programmers see themselves as analytic, logical thinkers instead—strong at reasoning, weak on artistic judgment, and incapable of doing UI design. In this brilliantly readable book, author Joel Spolsky proposes simple, logical rules that can be applied without any artistic talent to improve any user interface, from traditional GUI applications to websites to consumer electronics. Spolsky's primary axiom, the importance of bringing the program model in line with the user model, is both rational and simple. In a fun and entertaining way, Spolky makes user interface design easy for programmers to grasp. After reading User Interface Design for Programmers, you'll know how to design interfaces with the user in mind. You'll learn the important principles that underlie all good UI design, and you'll learn how to perform usability testing that works.
Multimedia Interaction and Intelligent User Interfaces
Author: Ling Shao
Publisher: Springer Science & Business Media
ISBN: 1849965072
Category : Computers
Languages : en
Pages : 306
Book Description
Consumer electronics (CE) devices, providing multimedia entertainment and enabling communication, have become ubiquitous in daily life. However, consumer interaction with such equipment currently requires the use of devices such as remote controls and keyboards, which are often inconvenient, ambiguous and non-interactive. An important challenge for the modern CE industry is the design of user interfaces for CE products that enable interactions which are natural, intuitive and fun. As many CE products are supplied with microphones and cameras, the exploitation of both audio and visual information for interactive multimedia is a growing field of research. Collecting together contributions from an international selection of experts, including leading researchers in industry, this unique text presents the latest advances in applications of multimedia interaction and user interfaces for consumer electronics. Covering issues of both multimedia content analysis and human-machine interaction, the book examines a wide range of techniques from computer vision, machine learning, audio and speech processing, communications, artificial intelligence and media technology. Topics and features: introduces novel computationally efficient algorithms to extract semantically meaningful audio-visual events; investigates modality allocation in intelligent multimodal presentation systems, taking into account the cognitive impacts of modality on human information processing; provides an overview on gesture control technologies for CE; presents systems for natural human-computer interaction, virtual content insertion, and human action retrieval; examines techniques for 3D face pose estimation, physical activity recognition, and video summary quality evaluation; discusses the features that characterize the new generation of CE and examines how web services can be integrated with CE products for improved user experience. This book is an essential resource for researchers and practitioners from both academia and industry working in areas of multimedia analysis, human-computer interaction and interactive user interfaces. Graduate students studying computer vision, pattern recognition and multimedia will also find this a useful reference.
Publisher: Springer Science & Business Media
ISBN: 1849965072
Category : Computers
Languages : en
Pages : 306
Book Description
Consumer electronics (CE) devices, providing multimedia entertainment and enabling communication, have become ubiquitous in daily life. However, consumer interaction with such equipment currently requires the use of devices such as remote controls and keyboards, which are often inconvenient, ambiguous and non-interactive. An important challenge for the modern CE industry is the design of user interfaces for CE products that enable interactions which are natural, intuitive and fun. As many CE products are supplied with microphones and cameras, the exploitation of both audio and visual information for interactive multimedia is a growing field of research. Collecting together contributions from an international selection of experts, including leading researchers in industry, this unique text presents the latest advances in applications of multimedia interaction and user interfaces for consumer electronics. Covering issues of both multimedia content analysis and human-machine interaction, the book examines a wide range of techniques from computer vision, machine learning, audio and speech processing, communications, artificial intelligence and media technology. Topics and features: introduces novel computationally efficient algorithms to extract semantically meaningful audio-visual events; investigates modality allocation in intelligent multimodal presentation systems, taking into account the cognitive impacts of modality on human information processing; provides an overview on gesture control technologies for CE; presents systems for natural human-computer interaction, virtual content insertion, and human action retrieval; examines techniques for 3D face pose estimation, physical activity recognition, and video summary quality evaluation; discusses the features that characterize the new generation of CE and examines how web services can be integrated with CE products for improved user experience. This book is an essential resource for researchers and practitioners from both academia and industry working in areas of multimedia analysis, human-computer interaction and interactive user interfaces. Graduate students studying computer vision, pattern recognition and multimedia will also find this a useful reference.
Seductive Interaction Design
Author: Stephen P. Anderson
Publisher: Pearson Education
ISBN: 0132118637
Category : Computers
Languages : en
Pages : 562
Book Description
What happens when you’ve built a great website or app, but no one seems to care? How do you get people to stick around long enough to see how your service might be of value? In Seductive Interaction Design, speaker and author Stephen P. Anderson takes a fresh approach to designing sites and interactions based on the stages of seduction. This beautifully designed book examines what motivates people to act. Topics include: AESTHETICS, BEAUTY, AND BEHAVIOR: Why do striking visuals grab our attention? And how do emotions affect judgment and behavior? PLAYFUL SEDUCTION: How do you create playful engagements during the moment? Why are serendipity, arousal, rewards, and other delights critical to a good experience? THE SUBTLE ART OF SEDUCTION: How do you put people at ease through clear and suggestive language? What are some subtle ways to influence behavior and get people to move from intent to action? THE GAME OF SEDUCTION: How do you continue motivating people long after the first encounter? Are there lessons to be gained from learning theories or game design? Principles from psychology are found throughout the book, along with dozens of examples showing how these techniques have been applied with great success. In addition, each section includes interviews with influential web and interaction designers.
Publisher: Pearson Education
ISBN: 0132118637
Category : Computers
Languages : en
Pages : 562
Book Description
What happens when you’ve built a great website or app, but no one seems to care? How do you get people to stick around long enough to see how your service might be of value? In Seductive Interaction Design, speaker and author Stephen P. Anderson takes a fresh approach to designing sites and interactions based on the stages of seduction. This beautifully designed book examines what motivates people to act. Topics include: AESTHETICS, BEAUTY, AND BEHAVIOR: Why do striking visuals grab our attention? And how do emotions affect judgment and behavior? PLAYFUL SEDUCTION: How do you create playful engagements during the moment? Why are serendipity, arousal, rewards, and other delights critical to a good experience? THE SUBTLE ART OF SEDUCTION: How do you put people at ease through clear and suggestive language? What are some subtle ways to influence behavior and get people to move from intent to action? THE GAME OF SEDUCTION: How do you continue motivating people long after the first encounter? Are there lessons to be gained from learning theories or game design? Principles from psychology are found throughout the book, along with dozens of examples showing how these techniques have been applied with great success. In addition, each section includes interviews with influential web and interaction designers.
Designing and Prototyping Interfaces with Figma
Author: Fabio Staiano
Publisher: Packt Publishing Ltd
ISBN: 180056192X
Category : Computers
Languages : en
Pages : 382
Book Description
Discover user experience and user interface design best practices while mastering a wide array of tools across Figma and FigJam with this full-color guide Key Features Learn the basics of user experience research, result organization, and analysis in FigJam Create mockups, interactive animations, and high-fidelity prototypes using this platform-independent web application tool Collaborate with a team in real-time and create, share, and test your designs Book Description A driving force of the design tools market, Figma makes it easy to work with classic design features while enabling unique innovations and opening up real-time collaboration possibilities. It comes as no surprise that many designers decide to switch from other tools to Figma. In this book, you'll be challenged to design a user interface for a responsive mobile application having researched and understood user needs. You'll become well-versed with the process in a step-by-step manner by exploring the theory first and gradually moving on to practice. You'll begin your learning journey by covering the basics of user experience research with FigJam and the process of creating a complete design using Figma tools such as Components, Variants, Auto Layout, and much more. You'll also learn how to prototype your design and explore the potential of community resources such as templates and plugins. By the end of this Figma book, you'll have a solid understanding of the user interface workflow, managing essential Figma tools, and organizing your workflow. What you will learn Explore FigJam and how to use it to collect data in the research phase Wireframe the future interface with shape tools and vectors Define grids, typography, colors, and effect styles that can be reused in your work Get to grips with Auto Layout and the constraints to create complex layouts Create flexible components using styles and variants Make your user interface interactive with prototyping and smart animate Share your work with others by exporting assets and preparing development resources Discover templates and plugins from the community Who this book is for This book is for aspiring UX/UI designers who want to get started with Figma as well as established designers who want to migrate to Figma from other design tools. This guide will take you through the entire process of creating a full-fledged prototype for a responsive interface using all the tools and features that Figma has to offer. As a result, this Figma design book is suitable for both UX and UI designers, product and graphic designers, and anyone who wants to explore the complete design process from scratch.
Publisher: Packt Publishing Ltd
ISBN: 180056192X
Category : Computers
Languages : en
Pages : 382
Book Description
Discover user experience and user interface design best practices while mastering a wide array of tools across Figma and FigJam with this full-color guide Key Features Learn the basics of user experience research, result organization, and analysis in FigJam Create mockups, interactive animations, and high-fidelity prototypes using this platform-independent web application tool Collaborate with a team in real-time and create, share, and test your designs Book Description A driving force of the design tools market, Figma makes it easy to work with classic design features while enabling unique innovations and opening up real-time collaboration possibilities. It comes as no surprise that many designers decide to switch from other tools to Figma. In this book, you'll be challenged to design a user interface for a responsive mobile application having researched and understood user needs. You'll become well-versed with the process in a step-by-step manner by exploring the theory first and gradually moving on to practice. You'll begin your learning journey by covering the basics of user experience research with FigJam and the process of creating a complete design using Figma tools such as Components, Variants, Auto Layout, and much more. You'll also learn how to prototype your design and explore the potential of community resources such as templates and plugins. By the end of this Figma book, you'll have a solid understanding of the user interface workflow, managing essential Figma tools, and organizing your workflow. What you will learn Explore FigJam and how to use it to collect data in the research phase Wireframe the future interface with shape tools and vectors Define grids, typography, colors, and effect styles that can be reused in your work Get to grips with Auto Layout and the constraints to create complex layouts Create flexible components using styles and variants Make your user interface interactive with prototyping and smart animate Share your work with others by exporting assets and preparing development resources Discover templates and plugins from the community Who this book is for This book is for aspiring UX/UI designers who want to get started with Figma as well as established designers who want to migrate to Figma from other design tools. This guide will take you through the entire process of creating a full-fledged prototype for a responsive interface using all the tools and features that Figma has to offer. As a result, this Figma design book is suitable for both UX and UI designers, product and graphic designers, and anyone who wants to explore the complete design process from scratch.