New CLion plugin post

_posts/2023-08-31-introducing-new-conan-clion-plugin.markdown

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+---
+layout: post
+comments: false
+title: "Introducing the new CLion Conan Plugin compatible with 2.X"
+meta_title: "Unveiling the new Conan CLion Plugin for seamless C++ package management - Conan Blog"
+description: "Discover how the new Conan CLion plugin 2.X enhances C++ development, with a practical example using libcurl for loading images from the internet."
+permalink: /introducing-new-conan-clion-plugin/
+---
+
+In this post, we are thrilled to announce the launch of the new version of the Conan CLion
+Plugin, now compatible with the 2.X versions of Conan. The new plugin is designed to bring
+more ease and control to developers using CLion (with version higher than 2022.3) and
+Conan for C++ projects. We will walk you through the process of using this plugin with a
+practical example that uses [libcurl](https://curl.se/libcurl/) and
+[stb](https://github.com/nothings/stb) to download an image from the Internet, load it,
+and print it as ASCII art in the console.
+
+## How the plugin works
+
+Before explaining how to install, configure, and use the plugin, let's briefly discuss how
+it integrates Conan with CMake to create a seamless experience. This plugin utilizes
+[cmake-conan](https://github.com/conan-io/cmake-conan/tree/develop2), a [CMake dependency
+provider](https://cmake.org/cmake/help/latest/guide/using-dependencies/index.html#dependency-providers)
+for the Conan C and C++ package manager. It injects ``conan_provider.cmake`` using the
+``CMAKE_PROJECT_TOP_LEVEL_INCLUDES`` definition. This dependency provider will translate
+the CMake configuration to Conan. For instance, if you select a *Debug* profile in CLion,
+Conan will install and use the packages for *Debug*. 
+
+Bear in mind that *cmake-conan* activates the Conan integration every time CMake calls to
+``find_package()``, meaning that no library will be installed until the CMake configure
+step runs. At that point, Conan will try to install the required libraries and build them
+if needed.
+
+Also, note that as dependency providers are a relatively new feature in CMake, you will
+need CMake version >= 3.24 and Conan >= 2.0.5.
+
+## Installing the plugin
+
+To install the new Conan CLion plugin, navigate to the JetBrains marketplace. Open CLion,
+go to *Settings > Plugins*, then select the *Marketplace* tab. Search for the Conan plugin
+and click on the Install button. After restarting CLion, a new “Conan” tool tab will
+appear at the bottom of the IDE.
+
+## Creating a new CMake project
+
+First, create a new CMake project in CLion, as usual. 
+
+<p class="centered">
+    <img  src="{{ site.baseurl }}/assets/post_images/2023-08-31/clion-new-project.png" style="display: block; margin-left: auto; margin-right: auto;" alt="CLion new CMake project"/>
+</p>
+
+Then select the project location and the language standard you want to use, and click on
+"Create".
+
+## Configuring the plugin
+
+Go to the “Conan” tool tab at the bottom of the IDE. You will see that the only enabled
+action in the toolbar of the plugin is the one with the 🔧 (wrench) symbol, click on it. 
+
+<p class="centered">
+    <img  src="{{ site.baseurl }}/assets/post_images/2023-08-31/clion-configuration-1.png" style="display: block; margin-left: auto; margin-right: auto;" alt="Click wrench symbol"/>
+</p>
+
+The first thing you should do there is configuring the Conan client executable that's
+going to be used. You can point to one specifically installed in an arbitrary location on
+your system or you can select *"Use Conan installed in the system"* to use the one
+installed at the system level.
+
+<p class="centered">
+    <img  src="{{ site.baseurl }}/assets/post_images/2023-08-31/clion-configuration-2.png" style="display: block; margin-left: auto; margin-right: auto;" alt="Configure Conan path"/>
+</p>
+
+You will find there some options marked as default. Let's go through all of them.
+
+- First, you will see checkboxes to mark in which configurations Conan should manage the
+  dependencies. In our case, as we only have the Debug configuration, it's the only one
+  checked. Also, below that "Automatically add Conan support for all configurations" is
+  marked by default. That means that you don't have to worry about adding Conan support to
+  new build configurations because the plugin will automatically add Conan support by
+  default.
+
+- You can also see that there's a checkbox to let Conan change the default CLion settings
+  and run CMake sequentially instead of running it in parallel. This is needed as the
+  Conan cache is not yet concurrent up to Conan 2.0.9 version.
+
+Normally, if you are using the Conan plugin, you wouldn't want to unmark them. So leave
+them and let's create our project and add the libraries to it. So, click on the OK button
+and the plugin should be ready to use.
+
+After doing the initial configuration, you will notice that the list of libraries is now
+enabled and that the 🔄 (update) and 👁️ (inspect) symbols are also enabled. We will
+explain them later in detail.
+
+## Using the plugin
+
+Now that we have our plugin configured and ready, let's explore its usage with an example.
+For this, we will use [libcurl](https://curl.se/libcurl/) to download an image from the
+Internet, then [stb](https://github.com/nothings/stb) to load it, and some basic code to
+print it in the console as ASCII characters.
+
+We will not delve into the specific details of the code, as it is beyond the scope of this
+tutorial. However, all the source code for this example is available in the [Conan 2.0
+examples repo](https://github.com/conan-io/examples2/tree/main/examples/libraries/libcurl/download_image):
+
+
+### Adding the code
+
+First, open the *main.cpp* file that CLion generated and replace the example code with the code below (you can also copy it from the
+[repository](https://github.com/conan-io/examples2/tree/main/examples/libraries/libcurl/download_image/main.cpp)):
+
+```cpp
+#include <iostream>
+#include <curl/curl.h>
+#include <vector>
+#include <string>
+
+#define STB_IMAGE_IMPLEMENTATION
+#include <stb_image.h>
+
+// Size of ASCII art
+static const int new_width = 100;
+
+// Ascii gradient
+static const std::string ASCII_CHARS = " .:-=+#%@@"; // Inverted colors
+
+// Function to scale the luminance into an ASCII character
+char map_luminance_to_ascii(float luminance) {
+    size_t position = luminance * (ASCII_CHARS.size() - 1);
+    return ASCII_CHARS[position];
+}
+
+// Function to download image
+static size_t write_data(void* ptr, size_t size, size_t nmemb, void* stream) {
+    ((std::string*)stream)->append((char*)ptr, size * nmemb);
+    return size * nmemb;
+}
+
+std::string download_image(const std::string& url) {
+    CURL* curl = curl_easy_init();
+    std::string response_string;
+
+    curl_easy_setopt(curl, CURLOPT_URL, url.c_str());
+    curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
+    curl_easy_setopt(curl, CURLOPT_WRITEDATA, &response_string);
+    curl_easy_perform(curl);
+    curl_easy_cleanup(curl);
+
+    return response_string;
+}
+
+// Function to convert image to ASCII
+std::string image_to_ascii(const std::string& image_data) {
+    int width, height, channels;
+    unsigned char* data = stbi_load_from_memory(
+            reinterpret_cast<const stbi_uc*>(image_data.data()),
+            image_data.size(),
+            &width,
+            &height,
+            &channels,
+            0
+    );
+
+    int new_height = static_cast<int>(static_cast<double>(height) / width * new_width * 0.45);
+
+    std::string ascii_image;
+    for (int i = 0; i < new_height; ++i) {
+        for (int j = 0; j < new_width; ++j) {
+            int old_i = i * height / new_height;
+            int old_j = j * width / new_width;
+
+            float r = data[(old_i * width + old_j) * channels + 0] / 255.0f;
+            float g = data[(old_i * width + old_j) * channels + 1] / 255.0f;
+            float b = data[(old_i * width + old_j) * channels + 2] / 255.0f;
+            float luminance = (0.2126f * r + 0.7152f * g + 0.0722f * b); // Subtract the luminance from 1 to invert
+
+            ascii_image += map_luminance_to_ascii(luminance);
+        }
+        ascii_image += '\n';
+    }
+
+    stbi_image_free(data);
+    return ascii_image;
+}
+
+int main(int argc, char** argv) {
+    // Picture by Katarzyna Modrzejewska from pexels.com
+    std::string url = "https://images.pexels.com/photos/1314550/pexels-photo-1314550.jpeg";
+
+    if (argc > 1) {
+        url = argv[1];
+    }
+
+    std::string image_data = download_image(url);
+    std::cout << image_to_ascii(image_data);
+}
+```
+
+Essentially, this application accepts an image URL as an argument (or defaults to a
+specific one if not provided), and downloads it using *libcurl* with the
+``download_image()`` function. Subsequently, it reads the RGB values with *stb* and
+converts the luminance values to ASCII characters using the ``image_to_ascii()`` function.
+
+Currently, attempting to build this code will result in an error because we don't have the
+required libraries yet. Navigate to the library list and search for *libcurl*. Some
+information on how to add it to CMake will be displayed, along with a "Use in project"
+button. Select the version you want to use and click the button.
+
+<p class="centered">
+    <img  src="{{ site.baseurl }}/assets/post_images/2023-08-31/clion-use-libcurl.png" style="display: block; margin-left: auto; margin-right: auto;" alt="Select library and use"/>
+</p>
+
+Perform the same operation for *stb*.
+
+Now, if you click on the 👁️ (inspect) icon mentioned earlier, you will see all the
+libraries we added to the project. This includes basic target information for CMake and
+the necessary code snippets to add to CMake to use them.
+
+Conan stores information about the used packages in a *conandata.yml* file located in your
+project folder. This file is read by a *conanfile.py*, also created during this process.
+These files can be customized for advanced usage of the plugin, but please read the
+information in the corresponding files on how to do this properly.
+
+<p class="centered">
+    <img  src="{{ site.baseurl }}/assets/post_images/2023-08-31/clion-inspect.png" style="display: block; margin-left: auto; margin-right: auto;" alt="Inspect libraries"/>
+</p>
+
+Modify your *CMakeLists.txt* according to the instructions, which should result in something
+like this:
+
+```cmake
+cmake_minimum_required(VERSION 3.25)
+project(ascii_image)
+
+set(CMAKE_CXX_STANDARD 17)
+
+find_package(CURL)
+find_package(stb)
+
+add_executable(ascii_image main.cpp)
+
+target_link_libraries(ascii_image CURL::libcurl stb::stb)
+```
+
+After reloading the CMake project, you should see Conan installing the libraries in the
+CMake output tab. Once the configuration process is complete, you can build and run the
+project:
+
+<p class="centered">
+    <img  src="{{ site.baseurl }}/assets/post_images/2023-08-31/clion-output-cat.png" style="display: block; margin-left: auto; margin-right: auto;" alt="ASCII cat"/>
+</p>
+
+## Conclusions
+
+The new Conan CLion plugin, compatible with 2.X versions, is designed to provide seamless
+integration between the Conan package manager and the CLion IDE. The plugin offers a more
+intuitive interface, making it easier to manage your dependencies directly within CLion.
+We hope this tool enhances your development experience, and we eagerly await to see what
+you will build with it!