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(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
line wrap: on
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<HTML
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><TITLE
>SDL_SetPalette</TITLE
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><H1
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>SDL_SetPalette</H1
><DIV
CLASS="REFNAMEDIV"
><A
NAME="AEN1517"
></A
><H2
>Name</H2
>SDL_SetPalette&nbsp;--&nbsp;Sets the colors in the palette of an 8-bit surface.</DIV
><DIV
CLASS="REFSYNOPSISDIV"
><A
NAME="AEN1520"
></A
><H2
>Synopsis</H2
><DIV
CLASS="FUNCSYNOPSIS"
><A
NAME="AEN1521"
></A
><P
></P
><PRE
CLASS="FUNCSYNOPSISINFO"
>#include "SDL.h"</PRE
><P
><CODE
><CODE
CLASS="FUNCDEF"
>int <B
CLASS="FSFUNC"
>SDL_SetPalette</B
></CODE
>(SDL_Surface *surface, int flags, SDL_Color *colors, int firstcolor, int ncolors);</CODE
></P
><P
></P
></DIV
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1527"
></A
><H2
>Description</H2
><P
>Sets a portion of the palette for the given 8-bit surface.</P
><P
>Palettized (8-bit) screen surfaces with the
<TT
CLASS="LITERAL"
>SDL_HWPALETTE</TT
> flag have two palettes, a logical
palette that is used for mapping blits to/from the surface and a
physical palette (that determines how the hardware will map the colors
to the display). <A
HREF="sdlblitsurface.html"
>SDL_BlitSurface</A
>
always uses the logical palette when blitting surfaces (if it has to
convert between surface pixel formats). Because of this, it is often
useful to modify only one or the other palette to achieve various
special color effects (e.g., screen fading, color flashes, screen dimming).</P
><P
>This function can modify either the logical or physical palette by
specifing <TT
CLASS="LITERAL"
>SDL_LOGPAL</TT
> or
<TT
CLASS="LITERAL"
>SDL_PHYSPAL</TT
>the in the <TT
CLASS="PARAMETER"
><I
>flags</I
></TT
>
parameter.</P
><P
>When <TT
CLASS="PARAMETER"
><I
>surface</I
></TT
> is the surface associated with the current
display, the display colormap will be updated with the requested colors.  If
<TT
CLASS="LITERAL"
>SDL_HWPALETTE</TT
> was set in <A
HREF="sdlsetvideomode.html"
>SDL_SetVideoMode</A
> flags,
<TT
CLASS="FUNCTION"
>SDL_SetPalette</TT
> will always return <SPAN
CLASS="RETURNVALUE"
>1</SPAN
>,
and the palette is guaranteed to be set the way you desire, even if the window
colormap has to be warped or run under emulation.</P
><P
>The color components of a
<A
HREF="sdlcolor.html"
><SPAN
CLASS="STRUCTNAME"
>SDL_Color</SPAN
></A
> structure
are 8-bits in size, giving you a total of
256<SUP
>3</SUP
>=16777216 colors.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1547"
></A
><H2
>Return Value</H2
><P
>If <TT
CLASS="PARAMETER"
><I
>surface</I
></TT
> is not a palettized surface, this function
does nothing, returning <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>.  If all of the colors were set
as passed to <TT
CLASS="FUNCTION"
>SDL_SetPalette</TT
>, it will return
<SPAN
CLASS="RETURNVALUE"
>1</SPAN
>.  If not all the color entries were set exactly as
given, it will return <SPAN
CLASS="RETURNVALUE"
>0</SPAN
>, and you should look at the
surface palette to determine the actual color palette.</P
></DIV
><DIV
CLASS="REFSECT1"
><A
NAME="AEN1555"
></A
><H2
>Example</H2
><PRE
CLASS="PROGRAMLISTING"
>        /* Create a display surface with a grayscale palette */
        SDL_Surface *screen;
        SDL_Color colors[256];
        int i;
        .
        .
        .
        /* Fill colors with color information */
        for(i=0;i&#60;256;i++){
          colors[i].r=i;
          colors[i].g=i;
          colors[i].b=i;
        }

        /* Create display */
        screen=SDL_SetVideoMode(640, 480, 8, SDL_HWPALETTE);
        if(!screen){
          printf("Couldn't set video mode: %s\n", SDL_GetError());
          exit(-1);
        }

        /* Set palette */
        SDL_SetPalette(screen, SDL_LOGPAL|SDL_PHYSPAL, colors, 0, 256);
        .
        .
        .
        .</PRE
></DIV
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><H2
>See Also</H2
><P
><A
HREF="sdlsetcolors.html"
>SDL_SetColors</A
>,
<A
HREF="sdlsetvideomode.html"
>SDL_SetVideoMode</A
>,
<A
HREF="sdlsurface.html"
>SDL_Surface</A
>,
<A
HREF="sdlcolor.html"
>SDL_Color</A
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