created working backspace effective input example prototype

examples/text/text_backspace_input.c

@@ -0,0 +1,177 @@
+/*
+    WELCOME raylib EXAMPLES CONTRIBUTOR!
+
+    This is a basic template to anyone ready to contribute with some code example for the library,
+    here there are some guidelines on how to create an example to be included in raylib
+
+    1. File naming: <module>_<description> - Lower case filename, words separated by underscore,
+       no more than 3-4 words in total to describe the example. <module> referes to the primary
+       raylib module the example is more related with (code, shapes, textures, models, shaders, raudio).
+       i.e: core_input_multitouch, shapes_lines_bezier, shaders_palette_switch
+
+    2. Follow below template structure, example info should list the module, the short description
+       and the author of the example, twitter or github info could be also provided for the author.
+       Short description should also be used on the title of the window.
+
+    3. Code should be organized by sections:[Initialization]- [Update] - [Draw] - [De-Initialization]
+       Place your code between the dotted lines for every section, please don't mix update logic with drawing
+       and remember to unload all loaded resources.
+
+    4. Code should follow raylib conventions: https://github.com/raysan5/raylib/wiki/raylib-coding-conventions
+       Try to be very organized, using line-breaks appropiately.
+
+    5. Add comments to the specific parts of code the example is focus on.
+       Don't abuse with comments, try to be clear and impersonal on the comments.
+
+    6. Try to keep the example simple, under 300 code lines if possible. Try to avoid external dependencies.
+       Try to avoid defining functions outside the main(). Example should be as self-contained as possible.
+
+    7. About external resources, they should be placed in a [resources] folder and those resources
+       should be open and free for use and distribution. Avoid propietary content.
+
+    8. Try to keep the example simple but with a creative touch.
+       Simple but beautiful examples are more appealing to users!
+
+    9. In case of additional information is required, just come to raylib Discord channel: example-contributions
+
+    10. Have fun!
+
+    The following files should be updated when adding a new example, it's planned to create some
+    script to automatize this process but not available yet.
+
+     - raylib/examples/<category>/<category>_example_name.c
+     - raylib/examples/<category>/<category>_example_name.png
+     - raylib/examples/<category>/resources/*.*
+     - raylib/examples/Makefile
+     - raylib/examples/Makefile.Web
+     - raylib/examples/README.md
+     - raylib/projects/VS2022/examples/<category>_example_name.vcxproj
+     - raylib/projects/VS2022/raylib.sln
+     - raylib.com/common/examples.js
+     - raylib.com/examples/<category>/<category>_example_name.html
+     - raylib.com/examples/<category>/<category>_example_name.data
+     - raylib.com/examples/<category>/<category>_example_name.wasm
+     - raylib.com/examples/<category>/<category>_example_name.js
+*/
+
+/*******************************************************************************************
+*
+*   raylib [core] example - Backspace input
+*
+*   Example originally created with raylib 5.0, last time updated with raylib 5.0
+*
+*   Example contributed by benevo (@benev0) and reviewed by Ramon Santamaria (@raysan5)
+*
+*   Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
+*   BSD-like license that allows static linking with closed source software
+*
+*   Copyright (c) 2023 benevo (@benev0)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#define MAX_INPUT_CHARS 40
+
+
+bool isKeyChar(int);
+
+//------------------------------------------------------------------------------------
+// Program main entry point
+//------------------------------------------------------------------------------------
+int main(void)
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    const int screenWidth = 800;
+    const int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [text] example - backspace input");
+
+    char textField[MAX_INPUT_CHARS + 1] = "\0";
+    int usedSize = 0;
+
+    SetTargetFPS(1);
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+
+        int letter = GetCharPressed();
+        int key = GetKeyPressed();
+
+        if(key)
+            printf("%d, %d\n", letter, key);
+
+        while (key > 0 || letter > 0)
+        {
+
+            if (key == KEY_BACKSPACE && usedSize > 0)
+            {
+                textField[usedSize - 1] = 0;
+                usedSize--;
+                key = GetKeyPressed();
+            }
+            else if (!isKeyChar(key))
+            {
+                key = GetKeyPressed();
+            }
+            else if ((letter > 0) && (letter >= 32) && (letter <= 125) && (usedSize < MAX_INPUT_CHARS))
+            {
+                textField[usedSize] = (char) letter;
+                textField[usedSize + 1] = 0;
+                usedSize++;
+                letter = GetCharPressed();
+                key = GetKeyPressed();
+            }
+            else
+            {
+                letter = GetCharPressed();
+                key = GetKeyPressed();
+            }
+        }
+
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+
+            // TODO: Draw everything that requires to be drawn at this point:
+
+            DrawText(textField, 40, 200, 20, BLACK);  // Example
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}
+
+bool isKeyChar(int key)
+{
+    switch (key)
+    {
+    case KEY_SPACE:
+    case KEY_APOSTROPHE:
+    case KEY_COMMA...KEY_NINE:
+    case KEY_SEMICOLON:
+    case KEY_EQUAL:
+    case KEY_A...KEY_Z:
+    case KEY_LEFT_BRACKET...KEY_RIGHT_BRACKET:
+    case KEY_GRAVE:
+        return true;
+    default:
+        return false;
+    }
+}