Conventional signs and symbols are used in topographical maps to help people interpret the information presented. These signs and symbols have been standardized to ensure that all maps, regardless of where they are produced, are easy to understand. In this article, we will review the key conventional signs and symbols used in topographical maps and provide code examples as a reference.
Key Sign and Symbols Used in Topographical Maps
Contour lines: The primary convention used in topographical maps, contour lines, indicate the elevation of the land. These lines outline the shape of hills, ridges, and valleys, with each line separated by a consistent interval. The interval is usually a specific distance, and the difference in elevation between two adjacent contour lines is called the contour interval.
Spot elevations: Spot elevations, also known as benchmark elevations, are used to mark precise elevations on the map. These markings depict a specific point's height, which is usually shown as a small circle with a number in the center. Spot elevations are critical because they help people determine the precise elevation of any point along the contour lines.
Water bodies: Water bodies are marked with symbols that help people understand the size, location, and type of the body of water being depicted. For example, a blue line shows a river or a stream, while a blue circle shows a lake or a pond. These symbols are consistent across all topographical maps, ensuring that the reader can easily identify the bodies of water being depicted.
Settlements: Settlements, such as towns and villages, are shown using different symbols depending on their size and importance. For instance, cities are shown with bold lettering and are marked using a city symbol, whereas small villages are marked with a dot. These symbols help people understand the relative size of the settlement being depicted.
Vegetation: Vegetation is typically depicted using different colors and patterns to differentiate between forest, grasslands, and shrubbery. Each color and pattern combination represents a different type of vegetation, highlighting the diversity of the landscape being depicted.
Examples of Conventional Signs and Symbols in Topographical Maps
Let's take a closer look at some sample code snippets representing the conventional signs and symbols used in topographical maps.
Contour lines – Contour lines can be coded using a dashed line pattern, making them distinguishable from other map elements. The code snippet for contour lines could look like this:
.beginPath(); .moveTo(50, 100); // Move to the starting position of the contour line .lineTo(100, 150); // Draw a line to the end position of the line .lineWidth = 2; // Set the width of the line .setLineDash([5, 5]); // Set the dashed line pattern .stroke(); // Draw the line
Spot elevations – Spot elevations are generally depicted as small circles with a number in the center. A sample code snippet for spot elevations could look like this:
.beginPath(); .arc(100, 200, 5, 0, Math.PI * 2, false); // Draw a circle with a radius of 5 pixels .fillStyle = "black"; // Set the fill color of the circle to black .fill(); // Fill the circle .font = "bold 12px Arial"; // Set the font size and type .fillText("375", 105, 210); // Draw the number "375" inside the circle
Water bodies – Water bodies are generally depicted with a blue color, with a blue circle representing a lake or a pond. A sample code snippet for water bodies could look like this:
.beginPath(); .arc(150, 250, 20, 0, Math.PI * 2, false); // Draw a circle with a radius of 20 pixels .fillStyle = "blue"; // Set the fill color to blue .fill(); // Fill the circle
Settlements – Settlements such as towns and villages are shown with specific symbols based on their size and importance. A sample code snippet for a city symbol could look like this:
.beginPath(); .arc(200, 300, 30, 0, Math.PI * 2, false); // Draw a circle with a radius of 30 pixels .lineWidth = 5; // Set the line width of the circle to 5 pixels .strokeStyle = "black"; // Set the stroke color of the circle to black .stroke(); // Draw the circle .font = "bold 18px Arial"; // Set the font size and type .strokeText("City", 165, 310); // Draw the word "City" in bold type
Vegetation – Vegetation is depicted using different colors and patterns to differentiate between forest, grasslands, and shrubbery. A sample code snippet for a forest symbol could look like this:
.beginPath(); .arc(250, 350, 20, 0, Math.PI * 2, false); // Draw a circle with a radius of 20 pixels .fillStyle = "green"; // Set the fill color to green .fill(); // Fill the circle .lineWidth = 2; // Set the line width to 2 pixels .setLineDash([5, 5]); // Set the dashed line pattern .strokeStyle = "green"; // Set the stroke color to green .strokeRect(235, 335, 30, 30); // Draw a square around the circle
In conclusion, conventional signs and symbols play an essential role in topographical maps. They help people understand the information presented by depicting the landscape's features and details accurately. By standardizing these signs and symbols, topographical maps are easy to read and understand, regardless of their origin. The examples presented in this article provide a reference for how to code these conventional signs and symbols in a mapping application, making it easy for developers to include them in their projects.
Previous topics can refer to different subjects that have been previously discussed. Here are some examples of previous topics and some additional information about each one:
Climate change: Climate change is a critical issue that has been a popular topic for some time. Climate change refers to the process of global warming that is currently being experienced and the resulting impact on the environment. Climate change has been connected to the increase in greenhouse gases, resulting in the melting of glaciers, rising sea levels, and changes in weather patterns.
Artificial intelligence: Artificial intelligence has become a popular topic in recent years as technology rapidly develops. Artificial intelligence refers to the ability of machines to think and learn, and it can be used to help solve complex problems. AI has been used in many applications, from self-driving cars to voice assistants like Siri and Alexa.
Mental health: Mental health has been a crucial topic of discussion in recent years, as people become more aware of the importance of taking care of their mental health. Mental health refers to a person's emotional, psychological, and social well-being. Mental health issues can include depression, anxiety, addiction, and other disorders. It is essential to take care of mental health to lead a healthy and happy life.
Economic inequality: Economic inequality has been a persistent issue in many societies for a long time. Economic inequality refers to the unequal distribution of income and wealth among people in a society. This imbalance creates a situation where some people have an excess of resources, while others lack basic necessities like food, shelter, and healthcare. Addressing economic inequality requires creating more equitable structures and policies.
Sustainable development: Sustainable development is a concept that has gained popularity in recent years as people become more aware of the impact of human activity on the planet. Sustainable development refers to growth that considers environmental, social, and economic factors. Sustainable development aims to meet the needs of the present generation without compromising the ability of future generations to meet their needs.
In summary, previous topics can refer to a wide range of important subjects that have been discussed in different contexts. These topics impact individuals, communities, and the planet and require attention to mitigate their negative effects.
What are conventional signs and symbols used for in topographical maps?
Answer: Conventional signs and symbols are used in topographical maps to help people interpret the information presented. They have been standardized to ensure easy understanding across different maps.
What do contour lines represent in a topographical map?
Answer: Contour lines in a topographical map indicate the elevation of the land, and each line is separated by a consistent interval.
How are spot elevations depicted in topographical maps?
Answer: Spot elevations are marked as small circles with a number in the center, depicting a specific point's height.
What do symbols used for water bodies in topographical maps represent?
Answer: Symbols used for water bodies in topographical maps represent the size, location, and type of the body of water being depicted, such as a river or a lake.
Why is it important to use standardized signs and symbols across topographical maps?
Answer: It is crucial to use standardized signs and symbols across topographical maps to ensure that they are consistently understood by readers regardless of where they are produced. This helps to avoid confusion and ensures that maps are easy to read and understand.