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view docs/html/sdlevent.html @ 2884:9dde605c7540
Date: Fri, 19 Dec 2008 20:17:35 +0100
From: Couriersud
Subject: Re: Aw: Experience using SDL1.3 in sdlmame/Proposal for api additions
> For consistency you'd probably want:
> SDL_SetRenderDrawColor(Uint8 r, Uint8 g, Uint8 b, Uint8 a);
> SDL_SetRenderDrawBlendMode(SDL_BlendMode blendMode);
> SDL_RenderLine(int x1, int y1, int x2, int y2);
> SDL_RenderFill(SDL_Rect *rect);
>
> You probably also want to add API functions query the current state.
>
I have implemented the above api for the opengl, x11, directfb and
software renderers. I have also renamed *TEXTUREBLENDMODE* constants to
BLENDMODE*. The unix build compiles. The windows renderer still needs to
be updated, but I have no windows development machine at hand. Have a
look at the x11 renderer for a sample.
Vector games now run at 90% both on opengl and directfb in comparison to
sdlmame's own opengl renderer. The same applies to raster games.
The diff also includes
a) Changed XDrawRect to XFillRect in x11 renderer
b) A number of changes to fix blending and modulation issues in the
directfb renderer.
author | Sam Lantinga <slouken@libsdl.org> |
---|---|
date | Sat, 20 Dec 2008 12:00:00 +0000 |
parents | 85cbe9c892f4 |
children |
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<HTML ><HEAD ><TITLE >SDL_Event</TITLE ><META NAME="GENERATOR" CONTENT="Modular DocBook HTML Stylesheet Version 1.76b+ "><LINK REL="HOME" TITLE="SDL Library Documentation" HREF="index.html"><LINK REL="UP" TITLE="SDL Event Structures." HREF="eventstructures.html"><LINK REL="PREVIOUS" TITLE="SDL Event Structures." HREF="eventstructures.html"><LINK REL="NEXT" TITLE="SDL_ActiveEvent" HREF="sdlactiveevent.html"></HEAD ><BODY CLASS="REFENTRY" BGCOLOR="#FFF8DC" TEXT="#000000" LINK="#0000ee" VLINK="#551a8b" ALINK="#ff0000" ><DIV CLASS="NAVHEADER" ><TABLE SUMMARY="Header navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TH COLSPAN="3" ALIGN="center" >SDL Library Documentation</TH ></TR ><TR ><TD WIDTH="10%" ALIGN="left" VALIGN="bottom" ><A HREF="eventstructures.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlactiveevent.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><H1 ><A NAME="SDLEVENT" ></A >SDL_Event</H1 ><DIV CLASS="REFNAMEDIV" ><A NAME="AEN3711" ></A ><H2 >Name</H2 >SDL_Event -- General event structure</DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3714" ></A ><H2 >Structure Definition</H2 ><PRE CLASS="PROGRAMLISTING" >typedef union{ Uint8 type; SDL_ActiveEvent active; SDL_KeyboardEvent key; SDL_MouseMotionEvent motion; SDL_MouseButtonEvent button; SDL_JoyAxisEvent jaxis; SDL_JoyBallEvent jball; SDL_JoyHatEvent jhat; SDL_JoyButtonEvent jbutton; SDL_ResizeEvent resize; SDL_ExposeEvent expose; SDL_QuitEvent quit; SDL_UserEvent user; SDL_SysWMEvent syswm; } SDL_Event;</PRE ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3717" ></A ><H2 >Structure Data</H2 ><DIV CLASS="INFORMALTABLE" ><A NAME="AEN3719" ></A ><P ></P ><TABLE BORDER="0" CLASS="CALSTABLE" ><TBODY ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >type</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" >The type of event</TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >active</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlactiveevent.html" >Activation event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >key</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlkeyboardevent.html" >Keyboard event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >motion</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlmousemotionevent.html" >Mouse motion event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >button</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlmousebuttonevent.html" >Mouse button event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >jaxis</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoyaxisevent.html" >Joystick axis motion event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >jball</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoyballevent.html" >Joystick trackball motion event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >jhat</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoyhatevent.html" >Joystick hat motion event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >jbutton</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoybuttonevent.html" >Joystick button event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >resize</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlresizeevent.html" >Application window resize event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >expose</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlexposeevent.html" >Application window expose event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >quit</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlquitevent.html" >Application quit request event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >user</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdluserevent.html" >User defined event</A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="STRUCTFIELD" ><I >syswm</I ></TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlsyswmevent.html" >Undefined window manager event</A ></TD ></TR ></TBODY ></TABLE ><P ></P ></DIV ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3791" ></A ><H2 >Description</H2 ><P >The <SPAN CLASS="STRUCTNAME" >SDL_Event</SPAN > union is the core to all event handling is SDL, its probably the most important structure after <SPAN CLASS="STRUCTNAME" >SDL_Surface</SPAN >. <SPAN CLASS="STRUCTNAME" >SDL_Event</SPAN > is a union of all event structures used in SDL, using it is a simple matter of knowing which union member relates to which event <TT CLASS="STRUCTFIELD" ><I >type</I ></TT >.</P ><P ><DIV CLASS="INFORMALTABLE" ><A NAME="AEN3799" ></A ><P ></P ><TABLE BORDER="1" CLASS="CALSTABLE" ><THEAD ><TR ><TH ALIGN="LEFT" VALIGN="TOP" >Event <TT CLASS="STRUCTFIELD" ><I >type</I ></TT ></TH ><TH ALIGN="LEFT" VALIGN="TOP" >Event Structure</TH ></TR ></THEAD ><TBODY ><TR ><TD ALIGN="LEFT" VALIGN="MIDDLE" ><TT CLASS="LITERAL" >SDL_ACTIVEEVENT</TT ></TD ><TD ALIGN="LEFT" VALIGN="MIDDLE" ><A HREF="sdlactiveevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_ActiveEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_KEYDOWN/UP</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlkeyboardevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_KeyboardEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_MOUSEMOTION</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlmousemotionevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_MouseMotionEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_MOUSEBUTTONDOWN/UP</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlmousebuttonevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_MouseButtonEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_JOYAXISMOTION</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoyaxisevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_JoyAxisEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_JOYBALLMOTION</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoyballevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_JoyBallEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_JOYHATMOTION</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoyhatevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_JoyHatEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_JOYBUTTONDOWN/UP</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdljoybuttonevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_JoyButtonEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_QUIT</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlquitevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_QuitEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_SYSWMEVENT</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlsyswmevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_SysWMEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_VIDEORESIZE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlresizeevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_ResizeEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_VIDEOEXPOSE</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdlexposeevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_ExposeEvent</SPAN ></A ></TD ></TR ><TR ><TD ALIGN="LEFT" VALIGN="TOP" ><TT CLASS="LITERAL" >SDL_USEREVENT</TT ></TD ><TD ALIGN="LEFT" VALIGN="TOP" ><A HREF="sdluserevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_UserEvent</SPAN ></A ></TD ></TR ></TBODY ></TABLE ><P ></P ></DIV ></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3885" ></A ><H2 >Use</H2 ><P >The <SPAN CLASS="STRUCTNAME" >SDL_Event</SPAN > structure has two uses</P ><P ></P ><UL COMPACT="COMPACT" ><LI ><P >Reading events on the event queue</P ></LI ><LI ><P >Placing events on the event queue</P ></LI ></UL ><P >Reading events from the event queue is done with either <A HREF="sdlpollevent.html" ><TT CLASS="FUNCTION" >SDL_PollEvent</TT ></A > or <A HREF="sdlpeepevents.html" ><TT CLASS="FUNCTION" >SDL_PeepEvents</TT ></A >. We'll use <TT CLASS="FUNCTION" >SDL_PollEvent</TT > and step through an example.</P ><P >First off, we create an empty <SPAN CLASS="STRUCTNAME" >SDL_Event</SPAN > structure. <PRE CLASS="PROGRAMLISTING" >SDL_Event test_event;</PRE > <TT CLASS="FUNCTION" >SDL_PollEvent</TT > removes the next event from the event queue, if there are no events on the queue it returns <SPAN CLASS="RETURNVALUE" >0</SPAN > otherwise it returns <SPAN CLASS="RETURNVALUE" >1</SPAN >. We use a <TT CLASS="FUNCTION" >while</TT > loop to process each event in turn. <PRE CLASS="PROGRAMLISTING" >while(SDL_PollEvent(&test_event)) {</PRE > The <TT CLASS="FUNCTION" >SDL_PollEvent</TT > function take a pointer to an <SPAN CLASS="STRUCTNAME" >SDL_Event</SPAN > structure that is to be filled with event information. We know that if <TT CLASS="FUNCTION" >SDL_PollEvent</TT > removes an event from the queue then the event information will be placed in our <SPAN CLASS="STRUCTNAME" >test_event</SPAN > structure, but we also know that the <SPAN CLASS="emphasis" ><I CLASS="EMPHASIS" >type</I ></SPAN > of event will be placed in the <TT CLASS="STRUCTFIELD" ><I >type</I ></TT > member of <SPAN CLASS="STRUCTNAME" >test_event</SPAN >. So to handle each event <TT CLASS="STRUCTFIELD" ><I >type</I ></TT > seperately we use a <TT CLASS="FUNCTION" >switch</TT > statement. <PRE CLASS="PROGRAMLISTING" > switch(test_event.type) {</PRE > We need to know what kind of events we're looking for <SPAN CLASS="emphasis" ><I CLASS="EMPHASIS" >and</I ></SPAN > the event <TT CLASS="STRUCTFIELD" ><I >type</I ></TT >'s of those events. So lets assume we want to detect where the user is moving the mouse pointer within our application. We look through our event types and notice that <TT CLASS="LITERAL" >SDL_MOUSEMOTION</TT > is, more than likely, the event we're looking for. A little <A HREF="sdlmousemotionevent.html" >more</A > research tells use that <TT CLASS="LITERAL" >SDL_MOUSEMOTION</TT > events are handled within the <A HREF="sdlmousemotionevent.html" ><SPAN CLASS="STRUCTNAME" >SDL_MouseMotionEvent</SPAN ></A > structure which is the <TT CLASS="STRUCTFIELD" ><I >motion</I ></TT > member of <SPAN CLASS="STRUCTNAME" >SDL_Event</SPAN >. We can check for the <TT CLASS="LITERAL" >SDL_MOUSEMOTION</TT > event <TT CLASS="STRUCTFIELD" ><I >type</I ></TT > within our <TT CLASS="FUNCTION" >switch</TT > statement like so: <PRE CLASS="PROGRAMLISTING" > case SDL_MOUSEMOTION:</PRE > All we need do now is read the information out of the <TT CLASS="STRUCTFIELD" ><I >motion</I ></TT > member of <SPAN CLASS="STRUCTNAME" >test_event</SPAN >. <PRE CLASS="PROGRAMLISTING" > printf("We got a motion event.\n"); printf("Current mouse position is: (%d, %d)\n", test_event.motion.x, test_event.motion.y); break; default: printf("Unhandled Event!\n"); break; } } printf("Event queue empty.\n");</PRE ></P ><P >It is also possible to push events onto the event queue and so use it as a two-way communication path. Both <A HREF="sdlpushevent.html" ><TT CLASS="FUNCTION" >SDL_PushEvent</TT ></A > and <A HREF="sdlpeepevents.html" ><TT CLASS="FUNCTION" >SDL_PeepEvents</TT ></A > allow you to place events onto the event queue. This is usually used to place a <TT CLASS="LITERAL" >SDL_USEREVENT</TT > on the event queue, however you could use it to post fake input events if you wished. Creating your own events is a simple matter of choosing the event type you want, setting the <TT CLASS="STRUCTFIELD" ><I >type</I ></TT > member and filling the appropriate member structure with information. <PRE CLASS="PROGRAMLISTING" >SDL_Event user_event; user_event.type=SDL_USEREVENT; user_event.user.code=2; user_event.user.data1=NULL; user_event.user.data2=NULL; SDL_PushEvent(&user_event);</PRE ></P ></DIV ><DIV CLASS="REFSECT1" ><A NAME="AEN3942" ></A ><H2 >See Also</H2 ><P ><A HREF="sdlpollevent.html" ><TT CLASS="FUNCTION" >SDL_PollEvent</TT ></A >, <A HREF="sdlpushevent.html" ><TT CLASS="FUNCTION" >SDL_PushEvent</TT ></A >, <A HREF="sdlpeepevents.html" ><TT CLASS="FUNCTION" >SDL_PeepEvents</TT ></A ></P ></DIV ><DIV CLASS="NAVFOOTER" ><HR ALIGN="LEFT" WIDTH="100%"><TABLE SUMMARY="Footer navigation table" WIDTH="100%" BORDER="0" CELLPADDING="0" CELLSPACING="0" ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" ><A HREF="eventstructures.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="index.html" ACCESSKEY="H" >Home</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" ><A HREF="sdlactiveevent.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL Event Structures.</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="eventstructures.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_ActiveEvent</TD ></TR ></TABLE ></DIV ></BODY ></HTML >