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[PATCH] SDL_GetVideoMode() does not find best mode, part 2 Following commit 1.51, I come accross a problem when SDL must choose between several video modes that could suit the one asked. If I ask 320x240 with this list: 768x480 768x240 640x400 640x200 384x480 384x240 320x400 320x200 The smallest selectables modes are 384x240 and 320x400. And SDL choose the later in this list, but 384x240 is more suitable. So I added a check to compare the pixel count (surface) of modes, and select the one which has the smallest pixel count. In my example, 384x240 has 92160 pixels, and 320x400 has 128000 pixels. So now SDL will choose 384x240 for the asked 320x240 mode.
author Patrice Mandin <patmandin@gmail.com>
date Thu, 19 Jan 2006 21:28:52 +0000
parents e5bc29de3f0a
children 546f7c1eb755
rev   line source
181
e5bc29de3f0a Updated from the SDL Documentation Project
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1 .TH "SDL_AudioSpec" "3" "Tue 11 Sep 2001, 22:58" "SDL" "SDL API Reference"
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2 .SH "NAME"
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3 SDL_AudioSpec\- Audio Specification Structure
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4 .SH "STRUCTURE DEFINITION"
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5 .PP
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6 .nf
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7 \f(CWtypedef struct{
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8 int freq;
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9 Uint16 format;
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10 Uint8 channels;
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11 Uint8 silence;
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12 Uint16 samples;
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13 Uint32 size;
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14 void (*callback)(void *userdata, Uint8 *stream, int len);
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15 void *userdata;
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16 } SDL_AudioSpec;\fR
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17 .fi
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18 .PP
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19 .SH "STRUCTURE DATA"
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20 .TP 20
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21 \fBfreq\fR
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22 Audio frequency in samples per second
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23 .TP 20
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24 \fBformat\fR
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25 Audio data format
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26 .TP 20
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27 \fBchannels\fR
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28 Number of channels: 1 mono, 2 stereo
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29 .TP 20
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30 \fBsilence\fR
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31 Audio buffer silence value (calculated)
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32 .TP 20
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33 \fBsamples\fR
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34 Audio buffer size in samples
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35 .TP 20
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36 \fBsize\fR
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37 Audio buffer size in bytes (calculated)
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38 .TP 20
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39 \fBcallback(\&.\&.)\fR
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40 Callback function for filling the audio buffer
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41 .TP 20
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42 \fBuserdata\fR
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43 Pointer the user data which is passed to the callback function
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44 .SH "DESCRIPTION"
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45 .PP
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46 The \fBSDL_AudioSpec\fR structure is used to describe the format of some audio data\&. This structure is used by \fI\fBSDL_OpenAudio\fP\fR and \fI\fBSDL_LoadWAV\fP\fR\&. While all fields are used by \fBSDL_OpenAudio\fP only \fBfreq\fR, \fBformat\fR, \fBsamples\fR and \fBchannels\fR are used by \fBSDL_LoadWAV\fP\&. We will detail these common members here\&.
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47 .TP 20
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48 \fBfreq\fR
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49 The number of samples sent to the sound device every second\&. Common values are 11025, 22050 and 44100\&. The higher the better\&.
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50 .TP 20
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51 \fBformat\fR
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52 Specifies the size and type of each sample element
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53 .IP "\fBAUDIO_U8\fP" 10Unsigned 8-bit samples
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54 .IP "\fBAUDIO_S8\fP" 10Signed 8-bit samples
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55 .IP "\fBAUDIO_U16\fP or \fBAUDIO_U16LSB\fP" 10Unsigned 16-bit little-endian samples
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56 .IP "\fBAUDIO_S16\fP or \fBAUDIO_S16LSB\fP" 10Signed 16-bit little-endian samples
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57 .IP "\fBAUDIO_U16MSB\fP" 10Unsigned 16-bit big-endian samples
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58 .IP "\fBAUDIO_S16MSB\fP" 10Signed 16-bit big-endian samples
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59 .IP "\fBAUDIO_U16SYS\fP" 10Either \fBAUDIO_U16LSB\fP or \fBAUDIO_U16MSB\fP depending on you systems endianness
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60 .IP "\fBAUDIO_S16SYS\fP" 10Either \fBAUDIO_S16LSB\fP or \fBAUDIO_S16MSB\fP depending on you systems endianness
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61 .TP 20
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62 \fBchannels\fR
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63 The number of seperate sound channels\&. 1 is mono (single channel), 2 is stereo (dual channel)\&.
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64 .TP 20
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65 \fBsamples\fR
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66 When used with \fI\fBSDL_OpenAudio\fP\fR this refers to the size of the audio buffer in samples\&. A sample a chunk of audio data of the size specified in \fBformat\fR mulitplied by the number of channels\&. When the \fBSDL_AudioSpec\fR is used with \fI\fBSDL_LoadWAV\fP\fR \fBsamples\fR is set to 4096\&.
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67 .SH "SEE ALSO"
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68 .PP
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69 \fI\fBSDL_OpenAudio\fP\fR, \fI\fBSDL_LoadWAV\fP\fR
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70 ...\" created by instant / docbook-to-man, Tue 11 Sep 2001, 22:58