Mercurial > sdl-ios-xcode
view docs/html/cdrom.html @ 876:9e84d106ec19
(Said Max Horn on the SDL mailing list...)
Hi folks,
based on Eric Wing's patch, I created the attached patch which fixes
the OpenGL coordinate inversion bug in SDL. It works fine over here on
10.3 with Ryan's test program (which I also attached).
There is another change in it: I removed the "- 1" in the two lines
using CGDisplayPixelsHigh()... while I understand from a logical point
of view why they *should* be correct, I checked the actual values
computed that way, and they were off-by-one. After removing the " - 1",
the returned mouse coordinates are correct. I checked this by moving
the mouse to the screen top/bottom in fullscreen mode, BTW. With the
change, the proper values 0 and 479 are returned (in 640x480 mode).
Sam, you may still want to test on 10.1, it's very simple using Ryan's
minimal test code :-)
Cheers,
Max
(Here is the reproduction case for revision history's sake...)
/*
* To compile:
* gcc -o test test.c `sdl-config --cflags` `sdl-config --libs` -framework OpenGL
*
* --ryan.
*/
#include <stdio.h>
#include "SDL.h"
#include "SDL_opengl.h"
int main(int argc, char **argv)
{
Uint32 flags = SDL_OPENGL /* | SDL_FULLSCREEN */;
SDL_Surface *screen;
SDL_Event event;
int done = 0;
GLfloat ratio;
SDL_Init(SDL_INIT_VIDEO);
SDL_ShowCursor(0);
if ((argv[1]) && (strcmp(argv[1], "--grab") == 0))
SDL_WM_GrabInput(SDL_GRAB_ON);
screen = SDL_SetVideoMode(640, 480, 0, flags);
if (!screen)
return(42);
ratio = ((GLfloat) screen->w) / ((GLfloat) screen->h);
glClearColor( 0.0f, 0.0f, 0.0f, 0.0f );
glClearDepth( 1.0f );
glEnable( GL_DEPTH_TEST );
glDepthFunc( GL_LEQUAL );
glViewport( 0, 0, screen->w, screen->h);
glMatrixMode( GL_PROJECTION );
glLoadIdentity();
gluPerspective( 45.0f, ratio, 0.1f, 100.0f );
glMatrixMode( GL_MODELVIEW );
glLoadIdentity();
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
SDL_GL_SwapBuffers();
// eh, close enough.
#define MAX_X 6.12
#define MAX_Y 4.50
while (!done)
{
int x, y;
GLfloat glx, gly;
if (!SDL_WaitEvent(&event))
break;
switch (event.type)
{
case SDL_KEYUP:
if (event.key.keysym.sym == SDLK_ESCAPE)
done = 1;
break;
}
SDL_GetMouseState(&x, &y);
glx = ((((GLfloat) x) / ((GLfloat) screen->w)) - 0.5f) * MAX_X;
gly = ((((GLfloat) y) / ((GLfloat) screen->h)) - 0.5f) * MAX_Y;
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
glLoadIdentity();
glTranslatef(glx,-gly,-6.0f);
glBegin(GL_TRIANGLES);
glColor3f(1,0,0); glVertex3f( 0.00f, 0.25f, 0.00f);
glColor3f(0,1,0); glVertex3f(-0.25f, -0.25f, 0.00f);
glColor3f(0,0,1); glVertex3f( 0.25f, -0.25f, 0.00f);
glEnd();
SDL_GL_SwapBuffers();
}
SDL_Quit();
return(0);
}
/* end of test.c ... */
author | Ryan C. Gordon <icculus@icculus.org> |
---|---|
date | Mon, 22 Mar 2004 09:38:20 +0000 |
parents | 355632dca928 |
children |
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<HTML ><HEAD ><TITLE >CD-ROM</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 Reference" HREF="reference.html"><LINK REL="PREVIOUS" TITLE="SDL_CloseAudio" HREF="sdlcloseaudio.html"><LINK REL="NEXT" TITLE="SDL_CDNumDrives" HREF="sdlcdnumdrives.html"><META NAME="KEYWORD" CONTENT="cdrom"><META NAME="KEYWORD" CONTENT="function"></HEAD ><BODY CLASS="CHAPTER" 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="sdlcloseaudio.html" ACCESSKEY="P" >Prev</A ></TD ><TD WIDTH="80%" ALIGN="center" VALIGN="bottom" ></TD ><TD WIDTH="10%" ALIGN="right" VALIGN="bottom" ><A HREF="sdlcdnumdrives.html" ACCESSKEY="N" >Next</A ></TD ></TR ></TABLE ><HR ALIGN="LEFT" WIDTH="100%"></DIV ><DIV CLASS="CHAPTER" ><H1 ><A NAME="CDROM" ></A >Chapter 11. CD-ROM</H1 ><DIV CLASS="TOC" ><DL ><DT ><B >Table of Contents</B ></DT ><DT ><A HREF="sdlcdnumdrives.html" >SDL_CDNumDrives</A > -- Returns the number of CD-ROM drives on the system.</DT ><DT ><A HREF="sdlcdname.html" >SDL_CDName</A > -- Returns a human-readable, system-dependent identifier for the CD-ROM.</DT ><DT ><A HREF="sdlcdopen.html" >SDL_CDOpen</A > -- Opens a CD-ROM drive for access.</DT ><DT ><A HREF="sdlcdstatus.html" >SDL_CDStatus</A > -- Returns the current status of the given drive.</DT ><DT ><A HREF="sdlcdplay.html" >SDL_CDPlay</A > -- Play a CD</DT ><DT ><A HREF="sdlcdplaytracks.html" >SDL_CDPlayTracks</A > -- Play the given CD track(s)</DT ><DT ><A HREF="sdlcdpause.html" >SDL_CDPause</A > -- Pauses a CDROM</DT ><DT ><A HREF="sdlcdresume.html" >SDL_CDResume</A > -- Resumes a CDROM</DT ><DT ><A HREF="sdlcdstop.html" >SDL_CDStop</A > -- Stops a CDROM</DT ><DT ><A HREF="sdlcdeject.html" >SDL_CDEject</A > -- Ejects a CDROM</DT ><DT ><A HREF="sdlcdclose.html" >SDL_CDClose</A > -- Closes a SDL_CD handle</DT ><DT ><A HREF="sdlcd.html" >SDL_CD</A > -- CDROM Drive Information</DT ><DT ><A HREF="sdlcdtrack.html" >SDL_CDtrack</A > -- CD Track Information Structure</DT ></DL ></DIV ><P >SDL supports audio control of up to 32 local CD-ROM drives at once.</P ><P >You use this API to perform all the basic functions of a CD player, including listing the tracks, playing, stopping, and ejecting the CD-ROM. (Currently, multi-changer CD drives are not supported.)</P ><P >Before you call any of the SDL CD-ROM functions, you must first call "<TT CLASS="FUNCTION" >SDL_Init(SDL_INIT_CDROM)</TT >", which scans the system for CD-ROM drives, and sets the program up for audio control. Check the return code, which should be <SPAN CLASS="RETURNVALUE" >0</SPAN >, to see if there were any errors in starting up.</P ><P >After you have initialized the library, you can find out how many drives are available using the <TT CLASS="FUNCTION" >SDL_CDNumDrives()</TT > function. The first drive listed is the system default CD-ROM drive. After you have chosen a drive, and have opened it with <TT CLASS="FUNCTION" >SDL_CDOpen()</TT >, you can check the status and start playing if there's a CD in the drive.</P ><P >A CD-ROM is organized into one or more tracks, each consisting of a certain number of "frames". Each frame is ~2K in size, and at normal playing speed, a CD plays 75 frames per second. SDL works with the number of frames on a CD, but this can easily be converted to the more familiar minutes/seconds format by using the <TT CLASS="FUNCTION" >FRAMES_TO_MSF()</TT > macro.</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="sdlcloseaudio.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="sdlcdnumdrives.html" ACCESSKEY="N" >Next</A ></TD ></TR ><TR ><TD WIDTH="33%" ALIGN="left" VALIGN="top" >SDL_CloseAudio</TD ><TD WIDTH="34%" ALIGN="center" VALIGN="top" ><A HREF="reference.html" ACCESSKEY="U" >Up</A ></TD ><TD WIDTH="33%" ALIGN="right" VALIGN="top" >SDL_CDNumDrives</TD ></TR ></TABLE ></DIV ></BODY ></HTML >