Review examples collection -WIP-

WARNING: Examples list has been reviewed but examples haven't been recompiled yet... that's not trivial...

1 files changed, 147 insertions, 0 deletions

diff --git a/examples/src/core/core_loading_thread.c b/examples/src/core/core_loading_thread.c
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+++ b/examples/src/core/core_loading_thread.c
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+/*******************************************************************************************
+*
+*   raylib example - loading thread
+*
+*   NOTE: This example requires linking with pthreads library, 
+*   on MinGW, it can be accomplished passing -static parameter to compiler
+*
+*   This example has been created using raylib 2.5 (www.raylib.com)
+*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+*
+*   Copyright (c) 2014-2019 Ramon Santamaria (@raysan5)
+*
+********************************************************************************************/
+
+#include "raylib.h"
+
+#include "pthread.h"                        // POSIX style threads management
+
+#include <stdatomic.h>                      // C11 atomic data types
+
+#include <time.h>                           // Required for: clock()
+
+// Using C11 atomics for synchronization
+// NOTE: A plain bool (or any plain data type for that matter) can't be used for inter-thread synchronization
+static atomic_bool dataLoaded = ATOMIC_VAR_INIT(false); // Data Loaded completion indicator
+static void *LoadDataThread(void *arg);     // Loading data thread function declaration
+
+static int dataProgress = 0;                // Data progress accumulator
+
+int main()
+{
+    // Initialization
+    //--------------------------------------------------------------------------------------
+    int screenWidth = 800;
+    int screenHeight = 450;
+
+    InitWindow(screenWidth, screenHeight, "raylib [core] example - loading thread");
+    
+    pthread_t threadId;             // Loading data thread id
+
+    enum { STATE_WAITING, STATE_LOADING, STATE_FINISHED } state = STATE_WAITING;
+    int framesCounter = 0;
+
+    SetTargetFPS(60);
+    //--------------------------------------------------------------------------------------
+
+    // Main game loop
+    while (!WindowShouldClose())    // Detect window close button or ESC key
+    {
+        // Update
+        //----------------------------------------------------------------------------------
+        switch (state)
+        {
+            case STATE_WAITING:
+            {
+                if (IsKeyPressed(KEY_ENTER))
+                {
+                    int error = pthread_create(&threadId, NULL, &LoadDataThread, NULL);
+                    if (error != 0) TraceLog(LOG_ERROR, "Error creating loading thread");
+                    else TraceLog(LOG_INFO, "Loading thread initialized successfully");
+
+                    state = STATE_LOADING;
+                }
+            } break;
+            case STATE_LOADING:
+            {
+                framesCounter++;
+                if (atomic_load(&dataLoaded))
+                {
+                    framesCounter = 0;
+                    state = STATE_FINISHED;
+                }
+            } break;
+            case STATE_FINISHED:
+            {
+                if (IsKeyPressed(KEY_ENTER))
+                {
+                    // Reset everything to launch again
+                    atomic_store(&dataLoaded, false);
+                    dataProgress = 0;
+                    state = STATE_WAITING;
+                }
+            } break;
+            default: break;
+        }
+        //----------------------------------------------------------------------------------
+
+        // Draw
+        //----------------------------------------------------------------------------------
+        BeginDrawing();
+
+            ClearBackground(RAYWHITE);
+            
+            switch (state) 
+            {
+                case STATE_WAITING: DrawText("PRESS ENTER to START LOADING DATA", 150, 170, 20, DARKGRAY); break;
+                case STATE_LOADING:
+                {
+                    DrawRectangle(150, 200, dataProgress, 60, SKYBLUE);
+                    if ((framesCounter/15)%2) DrawText("LOADING DATA...", 240, 210, 40, DARKBLUE);
+                    
+                } break;
+                case STATE_FINISHED:
+                {
+                    DrawRectangle(150, 200, 500, 60, LIME);
+                    DrawText("DATA LOADED!", 250, 210, 40, GREEN);
+                    
+                } break;
+                default: break;
+            }
+            
+            DrawRectangleLines(150, 200, 500, 60, DARKGRAY);
+
+        EndDrawing();
+        //----------------------------------------------------------------------------------
+    }
+
+    // De-Initialization
+    //--------------------------------------------------------------------------------------
+    CloseWindow();        // Close window and OpenGL context
+    //--------------------------------------------------------------------------------------
+
+    return 0;
+}
+
+// Loading data thread function definition
+static void *LoadDataThread(void *arg)
+{
+    int timeCounter = 0;            // Time counted in ms
+    clock_t prevTime = clock();     // Previous time
+
+    // We simulate data loading with a time counter for 5 seconds
+    while (timeCounter < 5000) 
+    {
+        clock_t currentTime = clock() - prevTime;
+        timeCounter = currentTime*1000/CLOCKS_PER_SEC;
+        
+        // We accumulate time over a global variable to be used in
+        // main thread as a progress bar
+        dataProgress = timeCounter/10;
+    }
+
+    // When data has finished loading, we set global variable
+    atomic_store(&dataLoaded, true);
+
+    return NULL;
+}