I don't think that OpenGL ICD should advertise multi-sample formats via the
standard DescribePixelFormat.
http://www.opengl.org/registry/specs/ARB/wgl_pixel_format.txt states:
Indices are assigned to pixel formats in the following order:
1. Accelerated pixel formats that are displayable
2. Accelerated pixel formats that are displayable and which have
extended attributes
3. Generic pixel formats
4. Accelerated pixel formats that are non displayable
ChoosePixelFormat will never select pixel formats from either group
2 or group 4. Each pixel format in group 2 is required to appear
identical to some pixel format in group 1 when queried by
DescribePixelFormat. Consequently, ChoosePixelFormat will always
select a format from group 1 when it might otherwise have selected a
format from group 2. Pixel formats in group 4 cannot be accessed by
ChoosePixelFormat at all.
That is, IIUC, in order to discover multi-sampled formats one must get the the
number of pixel formats via
wglGetPixelFormatAttribivARB(WGL_NUMBER_PIXEL_FORMATS_ARB) instead of
numVisuals = DescribePixelFormat(hdc, 1, sizeof(PIXELFORMATDESCRIPTOR),
NULL);
if (numVisuals == 0)
return;
And I'm not even sure if it is OK to call DescribePixelFormat() with extended
pixel formats or if one must use exclusively
wglGetPixelFormatAttribivARB/wglGetPixelFormatAttribivARB. You can see how
GLFW does it on https://github.com/glfw/glfw/blob/master/src/wgl_context.c#L144
Jose
----- Original Message -----
> Before, we always reported zeros in the multisample columns of the
> format list. Since PIXELFORMATDESCRIPTOR doesn't have fields for
> multisample, we use a new format_info structure to extend that type.
> ---
> src/wgl/wglinfo.c | 145
> +++++++++++++++++++++++++++++++++--------------------
> 1 file changed, 91 insertions(+), 54 deletions(-)
>
> diff --git a/src/wgl/wglinfo.c b/src/wgl/wglinfo.c
> index 2b2c921..76478e2 100644
> --- a/src/wgl/wglinfo.c
> +++ b/src/wgl/wglinfo.c
> @@ -50,6 +50,18 @@ typedef enum
> } InfoMode;
>
>
> +static GLboolean have_WGL_ARB_pixel_format;
> +static GLboolean have_WGL_ARB_multisample;
> +
> +
> +/**
> + * An extension of PIXELFORMATDESCRIPTOR to handle multisample, etc.
> + */
> +struct format_info {
> + PIXELFORMATDESCRIPTOR pfd;
> + unsigned sampleBuffers, numSamples;
> +};
> +
>
> static LRESULT CALLBACK
> WndProc(HWND hWnd,
> @@ -159,6 +171,12 @@ print_screen_info(HDC _hdc, GLboolean limits, GLboolean
> singleLine)
> printf("WGL extensions:\n");
> print_extension_list(wglExtensions, singleLine);
> }
> + if (extension_supported("WGL_ARB_pixel_format", wglExtensions)) {
> + have_WGL_ARB_pixel_format = GL_TRUE;
> + }
> + if (extension_supported("WGL_ARB_multisample", wglExtensions)) {
> + have_WGL_ARB_multisample = GL_TRUE;
> + }
> }
> #endif
> printf("OpenGL vendor string: %s\n", glVendor);
> @@ -208,27 +226,27 @@ visual_render_type_name(BYTE iPixelType)
> }
>
> static void
> -print_visual_attribs_verbose(int iPixelFormat, LPPIXELFORMATDESCRIPTOR ppfd)
> +print_visual_attribs_verbose(int iPixelFormat, const struct format_info
> *info)
> {
> printf("Visual ID: %x generic=%d native=%d\n",
> iPixelFormat,
> - ppfd->dwFlags & PFD_GENERIC_FORMAT ? 1 : 0,
> - ppfd->dwFlags & PFD_DRAW_TO_WINDOW ? 1 : 0);
> + info->pfd.dwFlags & PFD_GENERIC_FORMAT ? 1 : 0,
> + info->pfd.dwFlags & PFD_DRAW_TO_WINDOW ? 1 : 0);
> printf(" bufferSize=%d level=%d renderType=%s doubleBuffer=%d
> stereo=%d\n",
> - 0 /* ppfd->bufferSize */, 0 /* ppfd->level */,
> - visual_render_type_name(ppfd->iPixelType),
> - ppfd->dwFlags & PFD_DOUBLEBUFFER ? 1 : 0,
> - ppfd->dwFlags & PFD_STEREO ? 1 : 0);
> + 0 /* info->pfd.bufferSize */, 0 /* info->pfd.level */,
> + visual_render_type_name(info->pfd.iPixelType),
> + info->pfd.dwFlags & PFD_DOUBLEBUFFER ? 1 : 0,
> + info->pfd.dwFlags & PFD_STEREO ? 1 : 0);
> printf(" rgba: cRedBits=%d cGreenBits=%d cBlueBits=%d
> cAlphaBits=%d\n",
> - ppfd->cRedBits, ppfd->cGreenBits,
> - ppfd->cBlueBits, ppfd->cAlphaBits);
> + info->pfd.cRedBits, info->pfd.cGreenBits,
> + info->pfd.cBlueBits, info->pfd.cAlphaBits);
> printf(" cAuxBuffers=%d cDepthBits=%d cStencilBits=%d\n",
> - ppfd->cAuxBuffers, ppfd->cDepthBits, ppfd->cStencilBits);
> + info->pfd.cAuxBuffers, info->pfd.cDepthBits,
> info->pfd.cStencilBits);
> printf(" accum: cRedBits=%d cGreenBits=%d cBlueBits=%d
> cAlphaBits=%d\n",
> - ppfd->cAccumRedBits, ppfd->cAccumGreenBits,
> - ppfd->cAccumBlueBits, ppfd->cAccumAlphaBits);
> + info->pfd.cAccumRedBits, info->pfd.cAccumGreenBits,
> + info->pfd.cAccumBlueBits, info->pfd.cAccumAlphaBits);
> printf(" multiSample=%d multiSampleBuffers=%d\n",
> - 0 /* ppfd->numSamples */, 0 /* ppfd->numMultisample */);
> + info->numSamples, info->sampleBuffers);
> }
>
>
> @@ -242,32 +260,32 @@ print_visual_attribs_short_header(void)
>
>
> static void
> -print_visual_attribs_short(int iPixelFormat, LPPIXELFORMATDESCRIPTOR ppfd)
> +print_visual_attribs_short(int iPixelFormat, const struct format_info *info)
> {
> char *caveat = "None";
>
> printf("0x%02x %2d %2d %2d %2d %2d %c%c %c %c %2d %2d %2d %2d %2d %2d
> %2d",
> iPixelFormat,
> - ppfd->dwFlags & PFD_GENERIC_FORMAT ? 1 : 0,
> - ppfd->dwFlags & PFD_DRAW_TO_WINDOW ? 1 : 0,
> + info->pfd.dwFlags & PFD_GENERIC_FORMAT ? 1 : 0,
> + info->pfd.dwFlags & PFD_DRAW_TO_WINDOW ? 1 : 0,
> 0,
> - 0 /* ppfd->bufferSize */,
> - 0 /* ppfd->level */,
> - ppfd->iPixelType == PFD_TYPE_RGBA ? 'r' : ' ',
> - ppfd->iPixelType == PFD_TYPE_COLORINDEX ? 'c' : ' ',
> - ppfd->dwFlags & PFD_DOUBLEBUFFER ? 'y' : '.',
> - ppfd->dwFlags & PFD_STEREO ? 'y' : '.',
> - ppfd->cRedBits, ppfd->cGreenBits,
> - ppfd->cBlueBits, ppfd->cAlphaBits,
> - ppfd->cAuxBuffers,
> - ppfd->cDepthBits,
> - ppfd->cStencilBits
> + 0 /* info->pfd.bufferSize */,
> + 0 /* info->pfd.level */,
> + info->pfd.iPixelType == PFD_TYPE_RGBA ? 'r' : ' ',
> + info->pfd.iPixelType == PFD_TYPE_COLORINDEX ? 'c' : ' ',
> + info->pfd.dwFlags & PFD_DOUBLEBUFFER ? 'y' : '.',
> + info->pfd.dwFlags & PFD_STEREO ? 'y' : '.',
> + info->pfd.cRedBits, info->pfd.cGreenBits,
> + info->pfd.cBlueBits, info->pfd.cAlphaBits,
> + info->pfd.cAuxBuffers,
> + info->pfd.cDepthBits,
> + info->pfd.cStencilBits
> );
>
> printf(" %2d %2d %2d %2d %2d %1d %s\n",
> - ppfd->cAccumRedBits, ppfd->cAccumGreenBits,
> - ppfd->cAccumBlueBits, ppfd->cAccumAlphaBits,
> - 0 /* ppfd->numSamples */, 0 /* ppfd->numMultisample */,
> + info->pfd.cAccumRedBits, info->pfd.cAccumGreenBits,
> + info->pfd.cAccumBlueBits, info->pfd.cAccumAlphaBits,
> + info->sampleBuffers, info->numSamples,
> caveat
> );
> }
> @@ -283,29 +301,29 @@ print_visual_attribs_long_header(void)
>
>
> static void
> -print_visual_attribs_long(int iPixelFormat, LPPIXELFORMATDESCRIPTOR ppfd)
> +print_visual_attribs_long(int iPixelFormat, const struct format_info *info)
> {
> printf("0x%2x %2d %11d %2d %2d %2d %4s %3d %3d %3d %3d %3d %3d",
> iPixelFormat,
> - ppfd->dwFlags & PFD_GENERIC_FORMAT ? 1 : 0,
> - ppfd->dwFlags & PFD_DRAW_TO_WINDOW ? 1 : 0,
> + info->pfd.dwFlags & PFD_GENERIC_FORMAT ? 1 : 0,
> + info->pfd.dwFlags & PFD_DRAW_TO_WINDOW ? 1 : 0,
> 0,
> - 0 /* ppfd->bufferSize */,
> - 0 /* ppfd->level */,
> - visual_render_type_name(ppfd->iPixelType),
> - ppfd->dwFlags & PFD_DOUBLEBUFFER ? 1 : 0,
> - ppfd->dwFlags & PFD_STEREO ? 1 : 0,
> - ppfd->cRedBits, ppfd->cGreenBits,
> - ppfd->cBlueBits, ppfd->cAlphaBits
> + 0 /* info->pfd.bufferSize */,
> + 0 /* info->pfd.level */,
> + visual_render_type_name(info->pfd.iPixelType),
> + info->pfd.dwFlags & PFD_DOUBLEBUFFER ? 1 : 0,
> + info->pfd.dwFlags & PFD_STEREO ? 1 : 0,
> + info->pfd.cRedBits, info->pfd.cGreenBits,
> + info->pfd.cBlueBits, info->pfd.cAlphaBits
> );
>
> printf(" %3d %4d %2d %3d %3d %3d %3d %2d %2d\n",
> - ppfd->cAuxBuffers,
> - ppfd->cDepthBits,
> - ppfd->cStencilBits,
> - ppfd->cAccumRedBits, ppfd->cAccumGreenBits,
> - ppfd->cAccumBlueBits, ppfd->cAccumAlphaBits,
> - 0 /* ppfd->numSamples */, 0 /* ppfd->numMultisample */
> + info->pfd.cAuxBuffers,
> + info->pfd.cDepthBits,
> + info->pfd.cStencilBits,
> + info->pfd.cAccumRedBits, info->pfd.cAccumGreenBits,
> + info->pfd.cAccumBlueBits, info->pfd.cAccumAlphaBits,
> + info->sampleBuffers, info->numSamples
> );
> }
>
> @@ -313,20 +331,25 @@ print_visual_attribs_long(int iPixelFormat,
> LPPIXELFORMATDESCRIPTOR ppfd)
> static void
> print_visual_info(HDC hdc, InfoMode mode)
> {
> - PIXELFORMATDESCRIPTOR pfd;
> + PFNWGLGETPIXELFORMATATTRIBIVARBPROC wglGetPixelFormatAttribivARB_func;
> + struct format_info info;
> int numVisuals, numWglVisuals;
> int i;
>
> + wglGetPixelFormatAttribivARB_func =
> + (PFNWGLGETPIXELFORMATATTRIBIVARBPROC)
> + wglGetProcAddress("wglGetPixelFormatAttribivARB");
> +
> numVisuals = DescribePixelFormat(hdc, 1, sizeof(PIXELFORMATDESCRIPTOR),
> NULL);
> if (numVisuals == 0)
> return;
>
> numWglVisuals = 0;
> for (i = 0; i < numVisuals; i++) {
> - if(!DescribePixelFormat(hdc, i, sizeof(PIXELFORMATDESCRIPTOR), &pfd))
> + if(!DescribePixelFormat(hdc, i, sizeof(PIXELFORMATDESCRIPTOR),
> &info.pfd))
> continue;
>
> - //if(!(pfd.dwFlags & PFD_SUPPORT_OPENGL))
> + //if(!(info.pfd.dwFlags & PFD_SUPPORT_OPENGL))
> // continue;
>
> ++numWglVisuals;
> @@ -340,18 +363,32 @@ print_visual_info(HDC hdc, InfoMode mode)
> print_visual_attribs_long_header();
>
> for (i = 0; i < numVisuals; i++) {
> - if(!DescribePixelFormat(hdc, i, sizeof(PIXELFORMATDESCRIPTOR), &pfd))
> + if(!DescribePixelFormat(hdc, i, sizeof(PIXELFORMATDESCRIPTOR),
> &info.pfd))
> continue;
>
> - //if(!(pfd.dwFlags & PFD_SUPPORT_OPENGL))
> + //if(!(info.pfd.dwFlags & PFD_SUPPORT_OPENGL))
> // continue;
>
> + if (have_WGL_ARB_pixel_format && have_WGL_ARB_multisample) {
> + int attribs[] = { WGL_SAMPLE_BUFFERS_ARB, WGL_SAMPLES_ARB };
> + int values[2], layer = 0;
> + if (wglGetPixelFormatAttribivARB_func(hdc, i, layer,
> + 2, attribs, values)) {
> + info.sampleBuffers = values[0];
> + info.numSamples = values[1];
> + }
> + else {
> + info.sampleBuffers = 0;
> + info.numSamples = 0;
> + }
> + }
> +
> if (mode == Verbose)
> - print_visual_attribs_verbose(i, &pfd);
> + print_visual_attribs_verbose(i, &info);
> else if (mode == Normal)
> - print_visual_attribs_short(i, &pfd);
> + print_visual_attribs_short(i, &info);
> else if (mode == Wide)
> - print_visual_attribs_long(i, &pfd);
> + print_visual_attribs_long(i, &info);
> }
> printf("\n");
> }
> --
> 1.7.10.4
>
> _______________________________________________
> mesa-dev mailing list
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> https://urldefense.proofpoint.com/v1/url?u=http://lists.freedesktop.org/mailman/listinfo/mesa-dev&k=oIvRg1%2BdGAgOoM1BIlLLqw%3D%3D%0A&r=NMr9uy2iTjWVixC0wOcYCWEIYhfo80qKwRgdodpoDzA%3D%0A&m=mIR8V6P%2FYoxEbnhUZudn2DC8YBTiHYlMkU%2FRwIHNl6I%3D%0A&s=62e7dd68a5ab08412f68fbcd48475f3f35c3aa10cd4290d53f30b4632ab3b800
>
Series is
Reviewed-by: Jose Fonseca <jfons...@vmware.com>
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