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--
--  raylib [shaders] example - Apply a shader to a 3d model
--
--  NOTE: This example requires raylib OpenGL 3.3 or ES2 versions for shaders support,
--        OpenGL 1.1 does not support shaders, recompile raylib to OpenGL 3.3 version.
--
--  NOTE: Shaders used in this example are #version 330 (OpenGL 3.3), to test this example
--        on OpenGL ES 2.0 platforms (Android, Raspberry Pi, HTML5), use #version 100 shaders
--        raylib comes with shaders ready for both versions, check raylib/shaders install folder
--
--  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)
--
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-- Initialization
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local screenWidth = 800
local screenHeight = 450

SetConfigFlags(FLAG.MSAA_4X_HINT)      -- Enable Multi Sampling Anti Aliasing 4x (if available)

InitWindow(screenWidth, screenHeight, "raylib [shaders] example - model shader")

-- Define the camera to look into our 3d world
local camera = Camera(Vector3(3.0, 3.0, 3.0), Vector3(0.0, 1.5, 0.0), Vector3(0.0, 1.0, 0.0), 45.0)

local dwarf = LoadModel("resources/model/dwarf.obj")                   -- Load OBJ model
local texture = LoadTexture("resources/model/dwarf_diffuse.png")       -- Load model texture
local shader = LoadShader("resources/shaders/glsl330/base.vs", 
                          "resources/shaders/glsl330/grayscale.fs")    -- Load model shader

dwarf.material.shader = shader            -- Set shader effect to 3d model
dwarf.material.texDiffuse = texture       -- Bind texture to model

local position = Vector3(0.0, 0.0, 0.0)   -- Set model position

-- Setup orbital camera
SetCameraMode(CameraMode.ORBITAL)             -- Set an orbital camera mode
SetCameraPosition(camera.position)        -- Set internal camera position to match our camera position
SetCameraTarget(camera.target)            -- Set internal camera target to match our camera target

SetTargetFPS(60)                          -- Set our game to run at 60 frames-per-second
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-- Main game loop
while not WindowShouldClose() do          -- Detect window close button or ESC key
    -- Update
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    camera = UpdateCamera(camera)         -- Update internal camera and our camera
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    -- Draw
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    BeginDrawing()

        ClearBackground(RAYWHITE)

        Begin3dMode(camera)

            DrawModel(dwarf, position, 2.0, WHITE)   -- Draw 3d model with texture

            DrawGrid(10, 1.0)     -- Draw a grid

        End3dMode()
        
        DrawText("(c) Dwarf 3D model by David Moreno", screenWidth - 200, screenHeight - 20, 10, GRAY)

        DrawFPS(10, 10)

    EndDrawing()
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end

-- De-Initialization
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UnloadShader(shader)       -- Unload shader
UnloadTexture(texture)     -- Unload texture
UnloadModel(dwarf)         -- Unload model

CloseWindow()              -- Close window and OpenGL context
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