raylib/docs/examples/web/shapes/shapes_logo_raylib_anim.c

/*******************************************************************************************
*
*   raylib [shapes] example - raylib logo animation (adapted for HTML5 platform)
*
*   This example has been created using raylib 1.4 (www.raylib.com)
*   raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
*
*   Copyright (c) 2014 Ramon Santamaria (@raysan5)
*
********************************************************************************************/

#include "raylib.h"

#if defined(PLATFORM_WEB)
    #include <emscripten/emscripten.h>
#endif

//----------------------------------------------------------------------------------
// Global Variables Definition
//----------------------------------------------------------------------------------
int screenWidth = 800;
int screenHeight = 450;

int logoPositionX;
int logoPositionY;

int framesCounter = 0;
int lettersCount = 0;

int topSideRecWidth = 16;
int leftSideRecHeight = 16;

int bottomSideRecWidth = 16;
int rightSideRecHeight = 16;

int state = 0;                  // Tracking animation states (State Machine)
float alpha = 1.0f;             // Useful for fading


//----------------------------------------------------------------------------------
// Module Functions Declaration
//----------------------------------------------------------------------------------
void UpdateDrawFrame(void);     // Update and Draw one frame

//----------------------------------------------------------------------------------
// Main Enry Point
//----------------------------------------------------------------------------------
int main()
{
    // Initialization
    //--------------------------------------------------------------------------------------
    InitWindow(screenWidth, screenHeight, "raylib [shapes] example - raylib logo animation");
    
    logoPositionX = screenWidth/2 - 128;
    logoPositionY = screenHeight/2 - 128;
    
#if defined(PLATFORM_WEB)
    emscripten_set_main_loop(UpdateDrawFrame, 0, 1);
#else
    SetTargetFPS(60);   // Set our game to run at 60 frames-per-second
    //--------------------------------------------------------------------------------------
    
    // Main game loop
    while (!WindowShouldClose())    // Detect window close button or ESC key
    {
        UpdateDrawFrame();
    }
#endif

    // De-Initialization
    //--------------------------------------------------------------------------------------
    CloseWindow();        // Close window and OpenGL context
    //--------------------------------------------------------------------------------------

    return 0;
}

//----------------------------------------------------------------------------------
// Module Functions Definition
//----------------------------------------------------------------------------------
void UpdateDrawFrame(void)
{
    // Update
    //----------------------------------------------------------------------------------
    if (state == 0)                 // State 0: Small box blinking
    {
        framesCounter++;

        if (framesCounter == 120)
        {
            state = 1;
            framesCounter = 0;      // Reset counter... will be used later...
        }
    }
    else if (state == 1)            // State 1: Top and left bars growing
    {
        topSideRecWidth += 4;
        leftSideRecHeight += 4;

        if (topSideRecWidth == 256) state = 2;
    }
    else if (state == 2)            // State 2: Bottom and right bars growing
    {
        bottomSideRecWidth += 4;
        rightSideRecHeight += 4;

        if (bottomSideRecWidth == 256) state = 3;
    }
    else if (state == 3)            // State 3: Letters appearing (one by one)
    {
        framesCounter++;

        if (framesCounter/12)       // Every 12 frames, one more letter!
        {
            lettersCount++;
            framesCounter = 0;
        }

        if (lettersCount >= 10)     // When all letters have appeared, just fade out everything
        {
            alpha -= 0.02f;

            if (alpha <= 0.0f)
            {
                alpha = 0.0f;
                state = 4;
            }
        }
    }
    else if (state == 4)            // State 4: Reset and Replay
    {
        if (IsKeyPressed('R'))
        {
            framesCounter = 0;
            lettersCount = 0;

        topSideRecWidth = 16;
        leftSideRecHeight = 16;

        bottomSideRecWidth = 16;
        rightSideRecHeight = 16;

            alpha = 1.0f;
            state = 0;          // Return to State 0
        }
    }
    //----------------------------------------------------------------------------------

    // Draw
    //----------------------------------------------------------------------------------
    BeginDrawing();

        ClearBackground(RAYWHITE);

        if (state == 0)
        {
            if ((framesCounter/15)%2) DrawRectangle(logoPositionX, logoPositionY, 16, 16, BLACK);
        }
        else if (state == 1)
        {
            DrawRectangle(logoPositionX, logoPositionY, topSideRecWidth, 16, BLACK);
            DrawRectangle(logoPositionX, logoPositionY, 16, leftSideRecHeight, BLACK);
        }
        else if (state == 2)
        {
            DrawRectangle(logoPositionX, logoPositionY, topSideRecWidth, 16, BLACK);
            DrawRectangle(logoPositionX, logoPositionY, 16, leftSideRecHeight, BLACK);

            DrawRectangle(logoPositionX + 240, logoPositionY, 16, rightSideRecHeight, BLACK);
            DrawRectangle(logoPositionX, logoPositionY + 240, bottomSideRecWidth, 16, BLACK);
        }
        else if (state == 3)
        {
            DrawRectangle(logoPositionX, logoPositionY, topSideRecWidth, 16, Fade(BLACK, alpha));
            DrawRectangle(logoPositionX, logoPositionY + 16, 16, leftSideRecHeight - 32, Fade(BLACK, alpha));

            DrawRectangle(logoPositionX + 240, logoPositionY + 16, 16, rightSideRecHeight - 32, Fade(BLACK, alpha));
            DrawRectangle(logoPositionX, logoPositionY + 240, bottomSideRecWidth, 16, Fade(BLACK, alpha));

            DrawRectangle(screenWidth/2 - 112, screenHeight/2 - 112, 224, 224, Fade(RAYWHITE, alpha));

            DrawText(SubText("raylib", 0, lettersCount), screenWidth/2 - 44, screenHeight/2 + 48, 50, Fade(BLACK, alpha));
        }
        else if (state == 4)
        {
            DrawText("[R] REPLAY", 340, 200, 20, GRAY);
        }

    EndDrawing();
    //----------------------------------------------------------------------------------
}