Leaderboard

Events tutorial The reason why I created this topic, is that a lot of people are struckeling with them. In this tutorial I will only discus the very basic of them. If you want more, then there is a list of links at the end with more information. If I made any mistakes in the code, please let me know because I am not going to test every part. What are events? (basic description) Events are something custom added by MTA to make it easier to bring scripting(Lua) closer to our game. If we do not have events, then the only thing we can do is give instructions to our game. But our code will never detect changes in our game. The same question again: "So what are the events?" Events are a way to communicate changes in our game to our scripts (or from our scripts). So for example my little ped(cat) gets ran over by a car. Then I really want to know about that, don't I? When an event activates, I describe this as: triggered (from the word trigger) Full wiki information can be found here: Event_system Before we can use events, what do we need to know? There are two things we need to know: The reason why it is triggered. <What happens?/when something happens?> In MTA this is the eventName of the event. (Example: you <ran over> my ped) Who is the one using the event? The event system in MTA is using elements as base (baseElement). This makes it easier to combine the what/when happens? with the one who is related to it. In MTA this is the source of the event. (Example: you ran over my <ped>) Trigger an event A scripting example: (this is not an official event) local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped triggerEvent("onPedRanOver", ped) In this example, a custom event gets triggered to tell you that my new created ped has been ranOver. The eventName is "onPedRanOver" and the baseElement is ped. local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) In this SERVERSIDE example, I am also adding an extra argument drunkDriver to use the player that ran over the ped. This is not required, but it makes it more complete. See syntax. Syntax bool triggerEvent ( string eventName, element baseElement, [ var argument1, ... ] ) TriggerEvent Receiving triggers Receiving triggers is a bit more complicated, because there are a lot of options for it. You can receive events by listening to them. It is like: You know that something is going to happen but you do not know when. The first step that you have to take is related to this question: "Do I want to receive a custom or not custom event?" Custom events are self created events. They only exist when a scripter makes them. Two lists of NOT CUSTOM EVENTS but default MTA events, serverside and clientside: Server_Scripting_Events Client_Scripting_Events Do I want to receive a CUSTOM event? In case of a custom event, you have to register/enable it first. If you do not enable it and trigger it, you will receive a warning/error about that in your debug console. Syntax bool addEvent ( string eventName [, bool allowRemoteTrigger = false ] ) AddEvent The example below, shows you how to enable a custom event only for trigger events within the same server/client side. addEvent("eventName") -- Is the same as: addEvent("eventName", false) If you put the second argument to false or not fill it in, this means that you can't communicate from the other server/client-side. This option is most likely used for security reasons. Some events shouldn't be able to trigger by the other side For example, worst case scenario: (remote events enabled for a default MTA event) Serverside code: addEvent("onPlayerWasted", true) Clientside code: triggerServerEvent("onPlayerWasted", player, 0, localPlayer, 0, 9, false) OnPlayerWasted If this event is enabled for remote trigger events, then it might be possible to cheating kills/deaths score. Of course, it is not likely that players can run their own clientside code, but it is not impossible in case of not trust able community resources. Enable a custom event for trigger events that crossing sides (From clientside to serverside. From serverside to clientside). addEvent("eventName", true) This event can now be used by remote trigger event functions. See list: Client to server TriggerClientEvent TriggerLatentClientEvent Server to client TriggerServerEvent TriggerLatentServerEvent Enable the event from our previous example: addEvent("onPedRanOver", false) local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) If you do not use cross triggering, then I recommend to use the addEvent function in the same resource as where you are going to trigger from. This makes sure that the event is already added and that you will never receive this kind of error/warning "Event isn't added". If you put it in another resource which hasn't started yet, then after triggering you would still receive that error/warning. Start listening The next step is to add the addEventHandler. This function is used to listen to events. When an event is triggered, this handler(addEventHandler) will call the function you have attached to it, in MTA this function is called the handlerFunction. Syntax bool addEventHandler ( string eventName, element attachedTo, function handlerFunction [, bool getPropagated = true, string priority = "normal" ] ) AddEventHandler Resource 1 addEvent("onPedRanOver", false) local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) Resource 2 function handlerFunction () end addEventHandler("onPedRanOver", root, handlerFunction) The first 3 arguments, the require ones: eventName attachedTo handlerFunction Making sure that the addEventHandler options are correct set-up. Resource 1 addEvent("onPedRanOver", false) local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) Resource 2 function handlerFunction () end addEventHandler("onPedRanOver", root, handlerFunction) There are two conditions for an eventHandler to call the handlerFunction. 1. The event has to be exactly the same. In this case the event "onPedRanOver" is the same in both resources. 2. In both functions, triggerEvent and addEventHandler is an element being used. This element has to be exactly the same. (from where you trigger as well as where you receive) <OR> The triggered element from resource 1, has to be a CHILD of the element in resource 2. The root element is the very top layer of the MTA element structure. It will accept all elements you want to use for your events. See the element tree: If you do not understand the element tree please read this page: Element_tree Source variable The source of an event is the element that triggers the event. This variable isn't passed as an parameter, but it is predefined. This means that it is already created before hand. Some predefined variables do only exist under special conditions. The source variable is one of those, it is a hidden and local variable which is only available when a function is called by an event. List of predefined variables. addEvent("onPedRanOver", false) -- local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) function handlerFunction (drunkDriver) iprint(source) -- ped element end addEventHandler("onPedRanOver", resourceRoot, handlerFunction) In this example the ped is the source. See how those two code blocks are connected: addEvent("onPedRanOver", false) -- local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) function handlerFunction (drunkDriver) iprint(source) -- ped element end addEventHandler("onPedRanOver", resourceRoot , handlerFunction) resourceRoot In some examples, you see people use the resourceRoot instead of the root element for their addEventHandlers. The resourceRoot is an element created by a resource. This element holds all elements of that resource as (in)direct children. In the example above, the resourceRoot as baseElement will not work, because there are two resources. Each resource has it's own resourceRoot element. The resourceRoot is accessible with the same keyword: resourceRoot, but if you were to inspect the element in multiple resources, then the user data (element identifier) value is not the same. outputChatBox(inspect(resourceRoot)) If we were to put everything in one resource, then it would work: ? addEvent("onPedRanOver", false) -- function handlerFunction () end addEventHandler("onPedRanOver", resourceRoot, handlerFunction) -- local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) In case of remote triggering, the resourceRoot in serverside and clientside is considered the same.(As long as they are part of the same resource) Why/when would we use resourceRoot? 1. Limit eventHandlers to the resource elements If you have 1000 markers in your server. One of the resources is for example a trucker mission, where you can get money by hitting markers. The resourceRoot element will make sure that the onMarkerHit event will only trigger for markers created by that resource. addEventHandler("onMarkerHit", resourceRoot, function () -- source element is the marker end) OnMarkerHit 2. Another benefit is that you are able to re-use the same eventNames. Resource 1 addEvent("onPedRanOver", false) function handlerFunction () end addEventHandler("onPedRanOver", resourceRoot, handlerFunction) -- local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) Resource 2 addEvent("onPedRanOver", false) function handlerFunction () end addEventHandler("onPedRanOver", resourceRoot, handlerFunction) -- local ped = createPed( 120, 5540.6654, 1020.55122, 1240.545 ) -- my ped local drunkDriver = getRandomPlayer() triggerEvent("onPedRanOver", ped, drunkDriver) These two resources do use the same event, but will not trigger each other their addEventHandlers. Warning: If root was used, then they will!!!! ;@ Lets cross triggering with resourceRoot! Clientside triggerServerEvent("example", resourceRoot) Serverside addEvent("example", true) -- second argument is true! cross triggering enabled! addEventHandler("example", resourceRoot, function () end) getPropagated In this bigger example we will be talking about the option getPropagated. If this option is disabled, it will not detect children any more. Keep reading! After that start code scanning from A, to B and then to C. Syntax addEventHandler bool addEventHandler ( string eventName, element attachedTo, function handlerFunction [, bool getPropagated = true, string priority = "normal" ] ) Example: Clientside -- A triggerServerEvent("onClientPlayerLoaded", resourceRoot) -- trigger an event to serverside --------------------------------------- -- C addEvent("onResponseServer", true) -- first listener addEventHandler("onResponseServer", resourceRoot, function () outputChatBox("getPropagated enabled") end, true) -- getPropagated true by default. -- second listener addEventHandler("onResponseServer", resourceRoot, function () outputChatBox("getPropagated disabled") end, false) -- getPropagated is false. Serverside -- B addEvent("onClientPlayerLoaded", true) -- second argument is true! cross triggering enabled! addEventHandler("onClientPlayerLoaded", resourceRoot, function () --[[ client is a predefined variable, which represents the client/player that communicates with the server More information about predefined variables: https://forum.multitheftauto.com/topic/33407-list-of-predefined-variables/ ]] triggerClientEvent(client, "onResponseServer", resourceRoot) -- first trigger event local element = createElement("randomElement") -- making a randomElement triggerClientEvent(client, "onResponseServer", element) -- second trigger event end) How does this this code works? A. When a client his code has been started, it will execute a triggerServerEvent. (It doesn't wait for any other clientside files to be loaded) B. The server receives the event. And sends two triggerClientEvents back: The first one is using the resourceRoot as baseElement. The second one is using a randomElement as baseElement. Both are using the event "onResponseServer" C. There are two addEventHandlers listening to the event: "onResponseServer" The first one is using getPropagated and the second one is not using getPropagated. The randomElement that is created, is by default an indirect child of the resourceRoot of the same resource. What will happen? When firing the first trigger event, both listeners will call their handlerFunction. But when firing the second trigger event, only the first listener will call it's handlerFunction. The randomElement is an indirect child of resourceRoot, but because getPropagated is disabled it will not call it's handlerFunction. Other tutorials related to this one: See also this tutorial about deeper limiting event ranges within your resource and reducing addEventHandlers https://forum.multitheftauto.com/topic/100069-tut-addeventhandler-on-a-group-of-elements-small-tutorial/ More information Full wiki information: Event_system A list of more information about triggering events: (Client to client / server to server) TriggerEvent Client to server TriggerClientEvent TriggerLatentClientEvent Server to client TriggerServerEvent TriggerLatentServerEvent A list of more information about receiving events: AddEvent AddEventHandler RemoveEventHandler Two lists of MTA events, serverside and clientside: (warning: not custom events) Server_Scripting_Events Client_Scripting_Events Cancel events CancelEvent WasEventCancelled (warning: custom events ONLY) GetCancelReason (Server only) Cancel latent events and their status GetLatentEventHandles CancelLatentEvent GetLatentEventStatus

Dear MTA community, I have been spending my last 8 weeks on mathematical problems. One of them is the 3D Frustum-Plane intersection that is used by GPUs to draw triangles onto your screen. If you want to learn more about this please consider reading this thread. Promotional Video: https://www.youtube.com/watch?v=RQy3Q4Xe110 Prerequisites This tutorial is aimed at people who are capable of scientific thinking and are willing to playfully learn with Lua code. To execute steps in this tutorial minimal knowledge of Linear Algebra and Lua is required. Required MTA Resource: https://github.com/quiret/mta_lua_3d_math Description of the math Imagine that we have got a frustum and a plane in a 3D room described by coordinates plus their boundaries. By intersecting both you obtain all coordinates on a screen along with their depth values. Now think about how your vision works. You see distant objects smaller than closer ones. You rotate your eyes to angles of vision. If we were to put this concept into terms of math we could say: the plane of vision is bigger in the distance than in close proximity. The frustum is a seamless row of vision planes starting from the pyramid tip to the bottom. How to use the MTA Resource Just download the GitHub repository into a folder of your MTA Resources, name it "math_3d_nonlin" and start it. You can execute the following commands for quick testing: send_bbuf: draws a simple depth test draw_model: draws the DFF file "gfriend.dff" Now we have got the basics out of the way. Time to start coding. Please create a new "_math_test.Lua" script file in the resource and include it server-side at the bottom of meta.xml. Tutorial: software rendering a plane on screen Open your _math_test.Lua and include the following code: local viewFrustum = createViewFrustum( createVector(0, 0, 0), -- position createVector(10, 0, 0), -- right createVector(0, 0, 10), -- up createVector(0, 20, 0) -- front ); local plane = createPlane( createVector(-3, 10, -3), createVector(6, 0, 0), createVector(0, 0, 6) ); local function task_draw_scene(thread) local bbuf = create_backbuffer(640, 480, 255, 255, 0, 50); local dbuf = createDepthBuffer(640, 480, 1); local time_start = getTickCount(); do local gotToDraw, numDrawn, numSkipped = draw_plane_on_bbuf(viewFrustum, bbuf, dbuf, plane, true); if ( gotToDraw ) then outputDebugString( "drawn " .. numDrawn .. " pixels (skipped " .. numSkipped .. ")" ); end end local time_end = getTickCount(); local ms_diff = ( time_end - time_start ); outputDebugString( "render time: " .. ms_diff .. "ms" ); taskUpdate( 1, "creating backbuffer color composition string" ); local bbuf_width_ushort = num_to_ushort_bytes( bbuf.width ); local bbuf_height_ushort = num_to_ushort_bytes( bbuf.height ); local pixels_str = table.concat(bbuf.items); local bbuf_string = pixels_str .. ( bbuf_width_ushort .. bbuf_height_ushort ); taskUpdate( false, "sending backbuffer to clients (render time: " .. ms_diff .. "ms)" ); local players = getElementsByType("player"); for m,n in ipairs(players) do triggerClientEvent(n, "onServerTransmitImage", root, bbuf_string); end outputDebugString("sent backbuffer to clients"); end addCommandHandler( "testdraw", function(player) spawnTask(task_draw_scene); end ); Result: Try executing the "testdraw" command. At the top of file you see the definition of our frustum cone as well as a plane. By calling the function "draw_plane_on_bbuf" we put color information into bbuf for exactly the pixels that make up the rectangle. If you change the plane definition to... local plane = createPlane( createVector(-2, 10, -4), createVector(6, 0, 3), createVector(-2, 0, 6) ); you instead get this image: Try changing around the coordinates of frustum and plane to obtain different pictures! Tutorial: software rendering a triangle on screen Take the same code as in the tutorial above but change line 19 to: local gotToDraw, numDrawn, numSkipped = draw_plane_on_bbuf(viewFrustum, bbuf, dbuf, plane, true, "tri"); This way we have changed the primitive type to triangle (rectangle is the default). Try executing the "testdraw" command again to inspect the new result! Tutorial: drawing a DFF file onto screen Instead of writing triangle definitions by hand we can take them from a DFF file instead. DFF files are storage of triangle and vertex information along with 3D rotation and translation information. By extacting the triangles from the DFF file we can put them into our algorithm to software-render them! Here is a related excerpt from math_server.Lua: local modelToDraw = false; do local modelFile = fileOpen("gfriend.dff"); if (modelFile) then modelToDraw = rwReadClump(modelFile); fileClose(modelFile); end end local function task_draw_model(thread) local bbuf = create_backbuffer(640, 480, 255, 255, 0, 50); local dbuf = createDepthBuffer(640, 480, 1); local time_start = getTickCount(); local num_triangles_drawn = 0; if (modelToDraw) then -- Setup the camera. local geom = modelToDraw.geomlist[1]; local mt = geom.morphTargets[1]; local centerSphere = mt.sphere; local camPos = viewFrustum.getPos(); camPos.setX(centerSphere.x); camPos.setY(centerSphere.y - 3.8); camPos.setZ(centerSphere.z); local camFront = viewFrustum.getFront(); camFront.setX(0); camFront.setY(5 + centerSphere.r * 2); camFront.setZ(0); local camRight = viewFrustum.getRight(); camRight.setX(centerSphere.r * 2); camRight.setY(0); camRight.getZ(0); local camUp = viewFrustum.getUp(); camUp.setX(0); camUp.setY(0); camUp.setZ(centerSphere.r * 2); local triPlane = createPlane( createVector(0, 0, 0), createVector(0, 0, 0), createVector(0, 0, 0) ); local vertices = modelToDraw.geomlist[1].morphTargets[1].vertices; local triangles = modelToDraw.geomlist[1].triangles; local tpos = triPlane.getPos(); local tu = triPlane.getU(); local tv = triPlane.getV(); for m,n in ipairs(triangles) do taskUpdate( m / #triangles, "drawing triangle #" .. m ); local vert1 = vertices[n.vertex1 + 1]; local vert2 = vertices[n.vertex2 + 1]; local vert3 = vertices[n.vertex3 + 1]; tpos.setX(vert1.x); tpos.setY(vert1.y); tpos.setZ(vert1.z); tu.setX(vert2.x - vert1.x); tu.setY(vert2.y - vert1.y); tu.setZ(vert2.z - vert1.z); tv.setX(vert3.x - vert1.x); tv.setY(vert3.y - vert1.y); tv.setZ(vert3.z - vert1.z); local gotToDraw, numDrawn, numSkipped = draw_plane_on_bbuf(viewFrustum, bbuf, dbuf, triPlane, false, "tri"); if (gotToDraw) and (numDrawn >= 1) then num_triangles_drawn = num_triangles_drawn + 1; end end end local time_end = getTickCount(); local ms_diff = ( time_end - time_start ); (...) end The code first loads a DFF file called "gfriend.dff" and stores it inside the "modelToDraw" variable. Once you execute the "draw_model" command the code looks up the first geometry in the DFF file and fetches all triangles associated with it. The rendering camera is set up to point at the middle of the model. Then all triangles are drawn one-by-one. https://twitter.com/rplgn/status/1230650912345067520 Try swapping the DFF file for another one, like biker.dff, and examine the results! Maybe extract a different DFF file from GTA:SA and replace gfriend.dff with that one. External references: math calculation on paper example: https://imgur.com/gallery/rLvln3X German thread on mta-sa.org: https://www.mta-sa.org/thread/38693-3d-frustum-ebene-schneidung-in-Lua/ Do you have any questions related to the math or the implementation? Do not shy away from asking! I want to provide you with as much insight as I can.

You forgot to put a comma after "client" in line 3, like this: addEvent("onPlayerReady", true); addEventHandler("onPlayerReady", root, function() triggerClientEvent(client, "onClientRecebeItemVar", root, item_ID, item_NOME, spawnedItem_ID, spawnedItem_NOME, spawnedItem_X, spawnedItem_Y, spawnedItem_Z) end) No problem. I am glad to help you!

Hello and welcome to the forums @Muhannad We have a separate forum section dedicated to coding support. In the future please create threads there if you're looking for feedback tips or help with your code. I'll have your thread moved there shortly, so please stick to this and get the help that you need on this very thread. For future reference: https://forum.multitheftauto.com/forum/71-scripting/

Farei uma pequena demostração : local emprego = {} function adicionar (player) emprego[player] = "ifood" end addCommandHandler("adicionar", adicionar) function verificar (player) if emprego[player] == "ifood" then outputChatBox("Tem Emprego de ifood.") else outputChatBox("Sem Emprego.") end end addCommandHandler("verificar", verificar) function remover (player) if emprego[player] == "ifood" then emprego[player] = nil --/> Removerá da Tabela. end end addCommandHandler("remover", remover)

Eu faria essa função no lado server-side, eu não sei sé é possível chama um marker do lado server-side, para o client-side, acho que isso dará erro. Ou pode fazer o seguinte, faça um marker invisível do lado client-side na mesma posição : local trabjob = createMarker(2384.421, 2088.01, 9.835, "cylinder", 1.1, 0,0,0,0) E então utilize o que o Jonas^ Passou acima.

Troque: if isElementWithinMarker (thePlayer, trabjob) then por if isElementWithinMarker (localPlayer, trabjob) then

Sim, é obrigatório substituir um que já existe no jogo. Bom, a solução que a galera geralmente usa, é colocar no lugar dos objeto de Casino, as fichas, saca. ID: 1866 Para mais ID's: https://dev.prineside.com/en/gtasa_samp_model_id/search/?q=pkr_

@theFADE Na verdade você não tentou nada, até porque esse exemplo eu que fiz pra um outro carinha que queria fazer essa mesma coisa, e esse código esta funcionando 100%, você que esta usando em server-side ao invés de cliente-side

It's official, MTASA has been bought and we are becoming SAMP. Future MTASA builds will be closed source and half the features removed. Have a nice day!