Tutorial6: Test FPS

source code:

require 'SWE'

SWE.SetDebug(true)                                                                                                     
local win = SWE.DisplayInit("Lua SWE: TestFPS(5000 Rects)", 800, 600, false)                                           
                                                                                                                       
local colors = {}                                                                                                      
for col in pairs(SWE.Color) do                                                                                         
    table.insert(colors, col)                                                                                          
end                                                                                                                    
                                                                                                                       
win.frs = SWE.FontRender.System()                                                                                      
win.fps = 0                                                                                                            
win.rects = {}                                                                                                         
                                                                                                                       
function RandomColorRect()                                                                                             
    local t = {}                                                                                                       
    local col = colors[math.random(#colors)]                                                                           
    local posx = math.random(win.width-32)                                                                                   
    local posy = math.random(win.height-32)                                                                                   
    t.color = SWE.Color[col]                                                                                           
    t.rect = SWE.Rect(posx, posy, 32, 32)                                                                              
    return t
end

for num = 1, 5000 do
    table.insert(win.rects, RandomColorRect())
end

function win.RenderWindow()
    win:RenderClear(SWE.Color.Navy)
    for num = 1, #win.rects do
        local t = win.rects[num]
        win:RenderRect(t.color, t.rect, true)
    end
    win:RenderText(win.frs, tostring(win.fps) .. " fps", SWE.Color.Black, win.width-20, win.height-20, SWE.Align.Right, SWE.Align.Bottom)
    print(win.fps, "fps")
    return true
end

function win.KeyPressEvent(key)
    if SWE.Key.ESCAPE == key then
        -- close scene, see SWE.MainLoop
        win:SetVisible(false)
        return true
    end
    return false
end

function win.SystemTickEvent(time)
    local index = math.random(#win.rects)
    win.rects[index] = RandomColorRect()
    SWE.DisplayDirty()
end

function win.SystemRenderEvent(time)
    local integral, fractal = math.modf(1000 / time)
    win.fps = integral
end

SWE.MainLoop(win)