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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 355632dca928
children
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<HTML
><HEAD
><TITLE
>SDL_AudioSpec</TITLE
><META
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><H1
><A
NAME="SDLAUDIOSPEC"
></A
>SDL_AudioSpec</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN6507"
></A
><H2
>Name</H2
>SDL_AudioSpec&nbsp;--&nbsp;Audio Specification Structure</DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6510"
></A
><H2
>Structure Definition</H2
><PRE
CLASS="PROGRAMLISTING"
>typedef struct{
  int freq;
  Uint16 format;
  Uint8 channels;
  Uint8 silence;
  Uint16 samples;
  Uint32 size;
  void (*callback)(void *userdata, Uint8 *stream, int len);
  void *userdata;
} SDL_AudioSpec;</PRE
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6513"
></A
><H2
>Structure Data</H2
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN6515"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>freq</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio frequency in samples per second</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio data format</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>channels</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Number of channels: 1 mono, 2 stereo</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>silence</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer silence value (calculated)</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer size in samples</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>size</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Audio buffer size in bytes (calculated)</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>callback(..)</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Callback function for filling the audio buffer</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>userdata</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>Pointer the user data which is passed to the callback function</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6550"
></A
><H2
>Description</H2
><P
>The <SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
> structure is used to describe the format of some audio data. This structure is used by <A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
> and <A
HREF="sdlloadwav.html"
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
></A
>. While all fields are used by <TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
> only <TT
CLASS="STRUCTFIELD"
><I
>freq</I
></TT
>, <TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
>, <TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
> and <TT
CLASS="STRUCTFIELD"
><I
>channels</I
></TT
> are used by <TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
>. We will detail these common members here.</P
><DIV
CLASS="INFORMALTABLE"
><A
NAME="AEN6564"
></A
><P
></P
><TABLE
BORDER="0"
CLASS="CALSTABLE"
><TBODY
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>freq</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>The number of samples sent to the sound device every second. Common values are 11025, 22050 and 44100. The higher the better.</P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>format</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
><P
>Specifies the size and type of each sample element
<P
></P
><DIV
CLASS="VARIABLELIST"
><DL
><DT
><TT
CLASS="LITERAL"
>AUDIO_U8</TT
></DT
><DD
><P
>Unsigned 8-bit samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S8</TT
></DT
><DD
><P
>Signed 8-bit samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_U16</TT
> or <TT
CLASS="LITERAL"
>AUDIO_U16LSB</TT
></DT
><DD
><P
>Unsigned 16-bit little-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S16</TT
> or <TT
CLASS="LITERAL"
>AUDIO_S16LSB</TT
></DT
><DD
><P
>Signed 16-bit little-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_U16MSB</TT
></DT
><DD
><P
>Unsigned 16-bit big-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S16MSB</TT
></DT
><DD
><P
>Signed 16-bit big-endian samples</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_U16SYS</TT
></DT
><DD
><P
>Either <TT
CLASS="LITERAL"
>AUDIO_U16LSB</TT
> or <TT
CLASS="LITERAL"
>AUDIO_U16MSB</TT
> depending on you systems endianness</P
></DD
><DT
><TT
CLASS="LITERAL"
>AUDIO_S16SYS</TT
></DT
><DD
><P
>Either <TT
CLASS="LITERAL"
>AUDIO_S16LSB</TT
> or <TT
CLASS="LITERAL"
>AUDIO_S16MSB</TT
> depending on you systems endianness</P
></DD
></DL
></DIV
></P
></TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>channels</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>The number of seperate sound channels. 1 is mono (single channel), 2 is stereo (dual channel).</TD
></TR
><TR
><TD
ALIGN="LEFT"
VALIGN="TOP"
><TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
></TD
><TD
ALIGN="LEFT"
VALIGN="TOP"
>When used with <A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
> this refers to the size of the audio buffer in samples. A sample a chunk of audio data of the size specified in <TT
CLASS="PARAMETER"
><I
>format</I
></TT
> mulitplied by the number of channels. When the <SPAN
CLASS="STRUCTNAME"
>SDL_AudioSpec</SPAN
> is used with <A
HREF="sdlloadwav.html"
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
></A
> <TT
CLASS="STRUCTFIELD"
><I
>samples</I
></TT
> is set to 4096.</TD
></TR
></TBODY
></TABLE
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN6639"
></A
><H2
>See Also</H2
><P
><A
HREF="sdlopenaudio.html"
><TT
CLASS="FUNCTION"
>SDL_OpenAudio</TT
></A
>,
<A
HREF="sdlloadwav.html"
><TT
CLASS="FUNCTION"
>SDL_LoadWAV</TT
></A
></P
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