Add raylib lua examples

1 files changed, 122 insertions, 0 deletions

diff --git a/examples/textures_particles_trail_blending.lua b/examples/textures_particles_trail_blending.lua
new file mode 100644
index 00000000..d5ba7841
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+++ b/examples/textures_particles_trail_blending.lua
@@ -0,0 +1,122 @@
+-------------------------------------------------------------------------------------------
+--
+--  raylib example - particles trail blending
+--
+--  This example has been created using raylib 1.6 (www.raylib.com)
+--  raylib is licensed under an unmodified zlib/libpng license (View raylib.h for details)
+--
+--  Copyright (c) 2014-2016 Ramon Santamaria (@raysan5)
+--
+-------------------------------------------------------------------------------------------
+
+MAX_PARTICLES = 200
+
+-- Particle structure with basic data
+struct.Particle {
+    position,
+    color,
+    alpha,
+    size,
+    rotation,
+    active        -- NOTE: Use it to activate/deactive particle
+}
+
+-- Initialization
+-------------------------------------------------------------------------------------------
+local screenWidth = 800
+local screenHeight = 450
+
+InitWindow(screenWidth, screenHeight, "raylib [textures] example - particles trail blending")
+
+-- Particles pool, reuse them!
+local mouseTail = {}
+
+-- Initialize particles
+for i = 1, MAX_PARTICLES do
+    mouseTail[i].position = Vector2(0, 0)
+    mouseTail[i].color = Color(GetRandomValue(0, 255), GetRandomValue(0, 255), GetRandomValue(0, 255), 255)
+    mouseTail[i].alpha = 1.0
+    mouseTail[i].size = GetRandomValue(1, 30)/20.0
+    mouseTail[i].rotation = GetRandomValue(0, 360)
+    mouseTail[i].active = false
+end
+
+local gravity = 3.0
+
+local smoke = LoadTexture("resources/smoke.png")
+
+local blending = BLEND.ALPHA
+
+SetTargetFPS(60)
+-------------------------------------------------------------------------------------------
+
+-- Main game loop
+while not WindowShouldClose() do            -- Detect window close button or ESC key
+    -- Update
+    ---------------------------------------------------------------------------------------
+    
+    -- Activate one particle every frame and Update active particles
+    -- NOTE: Particles initial position should be mouse position when activated
+    -- NOTE: Particles fall down with gravity and rotation... and disappear after 2 seconds (alpha = 0)
+    -- NOTE: When a particle disappears, active = false and it can be reused.
+    for i = 1, MAX_PARTICLES do
+        if (not mouseTail[i].active) then
+            mouseTail[i].active = true
+            mouseTail[i].alpha = 1.0
+            mouseTail[i].position = GetMousePosition()
+            i = MAX_PARTICLES
+        end
+    end
+
+    for i = 1, MAX_PARTICLES do
+        if (mouseTail[i].active) then
+            mouseTail[i].position.y = mouseTail[i].position.y + gravity
+            mouseTail[i].alpha = mouseTail[i].alpha - 0.01
+            
+            if (mouseTail[i].alpha <= 0.0) then mouseTail[i].active = false end
+            
+            mouseTail[i].rotation = mouseTail[i].rotation + 5.0
+        end
+    end
+    
+    if (IsKeyPressed(KEY.SPACE)) then
+        if (blending == BLEND.ALPHA) then blending = BLEND_ADDITIVE
+        else blending = BLEND.ALPHA end
+    end
+    ---------------------------------------------------------------------------------------
+
+    -- Draw
+    ---------------------------------------------------------------------------------------
+    BeginDrawing()
+
+        ClearBackground(DARKGRAY)
+        
+        BeginBlendMode(blending)
+
+            -- Draw active particles
+            for i = 1, MAX_PARTICLES do
+                if (mouseTail[i].active) then 
+                    DrawTexturePro(smoke, Rectangle(0, 0, smoke.width, smoke.height), 
+                        Rectangle(mouseTail[i].position.x, mouseTail[i].position.y, 
+                                  smoke.width*mouseTail[i].size, smoke.height*mouseTail[i].size),
+                        Vector2(smoke.width*mouseTail[i].size/2, smoke.height*mouseTail[i].size/2), 
+                        mouseTail[i].rotation, Fade(mouseTail[i].color, mouseTail[i].alpha)) end
+            end
+        
+        EndBlendMode()
+        
+        DrawText("PRESS SPACE to CHANGE BLENDING MODE", 180, 20, 20, BLACK)
+        
+        if (blending == BLEND_ALPHA) then DrawText("ALPHA BLENDING", 290, screenHeight - 40, 20, BLACK)
+        else DrawText("ADDITIVE BLENDING", 280, screenHeight - 40, 20, RAYWHITE) end
+        
+    EndDrawing()
+    ---------------------------------------------------------------------------------------
+end
+
+-- De-Initialization
+-------------------------------------------------------------------------------------------
+UnloadTexture(smoke)
+
+CloseWindow()        -- Close window and OpenGL context
+-------------------------------------------------------------------------------------------
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