/* Stores content of GPU's surface address registers of the surfaces that
* correspond to the windowRecords frontBuffers. Only called inside
* PsychFlipWindowBuffers() immediately before triggering a double-buffer
* swap. The values are used as reference values: If another readout of
* these registers shows values different from the ones stored preflip,
* then that is a certain indicator that bufferswap has happened.
*/
void PsychStoreGPUSurfaceAddresses(PsychWindowRecordType* windowRecord)
{
#if PSYCH_SYSTEM == PSYCH_OSX || PSYCH_SYSTEM == PSYCH_LINUX
int gpuMaintype, gpuMinortype;
// If we are called, we know that 'windowRecord' is an onscreen window.
int screenId = windowRecord->screenNumber;
// Just need to check if GPU low-level access is supported:
if (!PsychOSIsKernelDriverAvailable(screenId)) return;
// We only support Radeon GPU's with pre DCE-4 display engine, nothing more recent:
if (!PsychGetGPUSpecs(screenId, &gpuMaintype, &gpuMinortype, NULL, NULL) ||
(gpuMaintype != kPsychRadeon) || (gpuMinortype >= 0x40)) {
return;
}
// Driver is online: Read the registers, but only for primary crtc in a multi-crtc config:
windowRecord->gpu_preflip_Surfaces[0] = PsychOSKDReadRegister(screenId, (PsychScreenToCrtcId(screenId, 0) < 1) ? RADEON_D1GRPH_PRIMARY_SURFACE_ADDRESS : RADEON_D2GRPH_PRIMARY_SURFACE_ADDRESS, NULL);
windowRecord->gpu_preflip_Surfaces[1] = PsychOSKDReadRegister(screenId, (PsychScreenToCrtcId(screenId, 0) < 1) ? RADEON_D1GRPH_SECONDARY_SURFACE_ADDRESS : RADEON_D2GRPH_SECONDARY_SURFACE_ADDRESS, NULL);
#endif
return;
}
int PsychPrefStateGet_ScreenToCrtcId(int screenId, int rankId)
{
return(PsychScreenToCrtcId(screenId, rankId));
}
/* PsychWaitForBufferswapPendingOrFinished()
* Waits until a bufferswap for window windowRecord has either already happened or
* bufferswap is certain.
* Input values:
* windowRecord struct of onscreen window to monitor.
* timestamp = Deadline for abortion of flip detection at input.
*
* Return values:
* timestamp = System time at polling loop exit.
* beamposition = Beamposition at polling loop exit.
*
* Return value: FALSE if swap happened already, TRUE if swap is imminent.
*/
psych_bool PsychWaitForBufferswapPendingOrFinished(PsychWindowRecordType* windowRecord, double* timestamp, int *beamposition)
{
#if PSYCH_SYSTEM == PSYCH_OSX || PSYCH_SYSTEM == PSYCH_LINUX
int gpuMaintype, gpuMinortype;
CGDirectDisplayID displayID;
unsigned int primarySurface, secondarySurface;
unsigned int updateStatus;
double deadline = *timestamp;
// If we are called, we know that 'windowRecord' is an onscreen window.
int screenId = windowRecord->screenNumber;
// Retrieve display id and screen size spec that is needed later...
PsychGetCGDisplayIDFromScreenNumber(&displayID, screenId);
#define RADEON_D1GRPH_UPDATE 0x6144
#define RADEON_D2GRPH_UPDATE 0x6944
#define RADEON_SURFACE_UPDATE_PENDING 4
#define RADEON_SURFACE_UPDATE_TAKEN 8
// Just need to check if GPU low-level access is supported:
if (!PsychOSIsKernelDriverAvailable(screenId)) return(FALSE);
// We only support Radeon GPU's with pre DCE-4 display engine, nothing more recent:
if (!PsychGetGPUSpecs(screenId, &gpuMaintype, &gpuMinortype, NULL, NULL) ||
(gpuMaintype != kPsychRadeon) || (gpuMinortype >= 0x40)) {
return(FALSE);
}
// Driver is online. Enter polling loop:
while (TRUE) {
// Read surface address registers:
primarySurface = PsychOSKDReadRegister(screenId, (PsychScreenToCrtcId(screenId, 0) < 1) ? RADEON_D1GRPH_PRIMARY_SURFACE_ADDRESS : RADEON_D2GRPH_PRIMARY_SURFACE_ADDRESS, NULL);
secondarySurface = PsychOSKDReadRegister(screenId, (PsychScreenToCrtcId(screenId, 0) < 1) ? RADEON_D1GRPH_SECONDARY_SURFACE_ADDRESS : RADEON_D2GRPH_SECONDARY_SURFACE_ADDRESS, NULL);
// Read update status registers:
updateStatus = PsychOSKDReadRegister(screenId, (PsychScreenToCrtcId(screenId, 0) < 1) ? RADEON_D1GRPH_UPDATE : RADEON_D2GRPH_UPDATE, NULL);
PsychGetAdjustedPrecisionTimerSeconds(timestamp);
if (primarySurface!=windowRecord->gpu_preflip_Surfaces[0] || secondarySurface!=windowRecord->gpu_preflip_Surfaces[1] || (updateStatus & (RADEON_SURFACE_UPDATE_PENDING | RADEON_SURFACE_UPDATE_TAKEN)) || (*timestamp > deadline)) {
// Abort condition: Exit loop.
break;
}
if (PsychPrefStateGet_Verbosity() > 9) {
printf("PTB-DEBUG: Head %i: primarySurface=%p : secondarySurface=%p : updateStatus=%i\n", PsychScreenToCrtcId(screenId, 0), primarySurface, secondarySurface, updateStatus);
}
// Sleep slacky at least 200 microseconds, then retry:
PsychYieldIntervalSeconds(0.0002);
};
// Take timestamp and beamposition:
*beamposition = PsychGetDisplayBeamPosition(displayID, screenId);
PsychGetAdjustedPrecisionTimerSeconds(timestamp);
// Exit due to timeout?
if (*timestamp > deadline) {
// Mark timestamp as invalid due to timeout:
*timestamp = -1;
}
// Return FALSE if bufferswap happened already, TRUE if swap is still pending:
return((updateStatus & RADEON_SURFACE_UPDATE_PENDING) ? TRUE : FALSE);
#else
// On Windows, we always return "swap happened":
return(FALSE);
#endif
}
/* PsychFixupNative10BitFramebufferEnableAfterEndOfSceneMarker()
*
* Undo changes made by the graphics driver to the framebuffer pixel format control register
* as part of an OpenGL/Graphics op that marks "End of Scene", e.g., a glClear() command, that
* would revert the framebuffers opmode to standard 8bpc mode and thereby kill our 10 bpc mode
* setting.
*
* This routine *must* be called after each such problematic "End of scene" marker command like
* glClear(). The routine does nothing if 10bpc mode is not enabled/requested for the corresponding
* display head associated with the given onscreen window. It rewrites the control register on
* 10 bpc configured windows to basically undo the unwanted change of the gfx-driver *before*
* a vertical retrace cycle starts, ie., before that changes take effect (The register is double-
* buffered and latched to update only at VSYNC time, so we just have to be quick enough).
*
*
* Expected Sequence of operations is:
* 1. Some EOS command like glClear() issued.
* 2. EOS command schedules ctrl register update to "bad" value at next VSYNC.
* 3. This routine gets called, detects need for fixup, glGetError() waits for "2." to finish.
* 4. This routine undos the "bad" value change request by overwriting the latch with our
* "good" value --> Scheduled for next VSYNC. Then it returns...
* 5. At next VSYNC or old "good" value is overwritten/latched with our new old "good" value,
* --> "good value" persists, framebuffer stays in 2101010 configuration --> All good.
*
* So far the theory, let's see if this really works in real world...
*
* This is not needed in Carbon+AGL windowed mode, as the driver doesnt' mess with the control
* register there, but that mode has its own share of drawback, e.g., generally reduced performance
* and less robust stimulus onset timing and timestamping... Life's full of tradeoffs...
*/
void PsychFixupNative10BitFramebufferEnableAfterEndOfSceneMarker(PsychWindowRecordType* windowRecord)
{
#if PSYCH_SYSTEM == PSYCH_OSX || PSYCH_SYSTEM == PSYCH_LINUX
int headiter, headid, screenId;
unsigned int ctlreg, lutreg, val1, val2;
int gpuMaintype, gpuMinortype;
// Fixup needed? Only if 10bpc mode is supposed to be active! Early exit if not:
if (!(windowRecord->specialflags & kPsychNative10bpcFBActive)) return;
// Map windows screen to gfx-headid aka register subset. TODO : We'll need something better,
// more generic, abstracted out for the future, but as a starter this will do:
screenId = windowRecord->screenNumber;
// We only support Radeon GPU's, nothing else:
if (!PsychGetGPUSpecs(screenId, &gpuMaintype, &gpuMinortype, NULL, NULL) ||
(gpuMaintype != kPsychRadeon) || (gpuMinortype >= 0xffff)) {
return;
}
// This command must be called with the OpenGL context of the given windowRecord active, so
// we can rely on glGetError() waiting for the correct pipeline to settle! Wait via glGetError()
// for the end-of-scene marker to finish completely, so our register write happens after
// the "wrong" register write of that command. glFinish() doesn't work here for unknown
// reasons - probably it waits too long or whatever. Pretty shaky this stuff...
glGetError();
// Ok, now rewrite the double-buffered (latched) register with our "good" value for keeping
// the 10 bpc framebuffer online:
// Iterate over range of all assigned heads for this screenId 'i' and reconfigure them:
for (headiter = 0; headiter < kPsychMaxPossibleCrtcs; headiter++) {
// Map screenid to headid for headiter'th head:
headid = PsychScreenToCrtcId(screenId, headiter);
// We're done as soon as we encounter invalid negative headid.
if (headid < 0) break;
// Select Radeon HW registers for corresponding heads:
if (gpuMinortype < 0x40) {
// DCE-3 and earlier:
lutreg = (headid == 0) ? RADEON_D1GRPH_LUT_SEL : RADEON_D2GRPH_LUT_SEL;
ctlreg = (headid == 0) ? RADEON_D1GRPH_CONTROL : RADEON_D2GRPH_CONTROL;
}
else {
// DCE-4 and later:
if (headid > DCE4_MAXHEADID) {
printf("PTB-ERROR: Invalid headId %i (greater than max %i) provided for DCE-4+ display engine!\n", headid, DCE4_MAXHEADID);
return;
}
lutreg = EVERGREEN_DC_LUT_10BIT_BYPASS + crtcoff[headid];
ctlreg = EVERGREEN_GRPH_CONTROL + crtcoff[headid];
}
// Get current state of registers at high debug levels:
if (PsychPrefStateGet_Verbosity() > 9) {
val1 = PsychOSKDReadRegister(screenId, lutreg, NULL);
val2 = PsychOSKDReadRegister(screenId, ctlreg, NULL);
printf("PTB-DEBUG: PsychFixupNative10BitFramebufferEnableAfterEndOfSceneMarker(): Screen %i, head %i: LUT = %i [%i], GRPHCONT = %i [%i]\n", screenId, headid, val1 & (0x1 << 8), val1, val2 & (0x1 << 8), val2);
}
// One-liner read-modify-write op, which simply sets bit 8 of the register - the "10 bit LUT bypass" bit:
PsychOSKDWriteRegister(screenId, lutreg, (0x1 << 8) | PsychOSKDReadRegister(screenId, lutreg, NULL), NULL);
// One-liner read-modify-write op, which simply sets bit 8 of the register - the "Enable 2101010 mode" bit:
PsychOSKDWriteRegister(screenId, ctlreg, (0x1 << 8) | PsychOSKDReadRegister(screenId, ctlreg, NULL), NULL);
// Debug output, if wanted:
if (PsychPrefStateGet_Verbosity() > 5) printf("PTB-DEBUG: PsychFixupNative10BitFramebufferEnableAfterEndOfSceneMarker(): ARGB2101010 bit set on screen %i, head %i.\n", screenId, headid);
}
#endif
// Done.
return;
}
/* PsychEnableNative10BitFramebuffer() - Enable/Disable native 10 bpc RGB framebuffer modes.
*
* This function enables or disables the native ARGB2101010 framebuffer readout mode of supported
* graphics hardware. Currently the ATI Radeon X1000/HD2000/HD3000 and later cards should allow this.
*
* This needs support from the Psychtoolbox kernel level support driver for low-level register reads
* and writes to the GPU registers.
*
* 'windowRecord' Is used to find the Id of the screen for which mode should be changed, as well as enable
* flags to see if a change is required at all, and the OpenGL context for some specific
* fixups. A value of NULL will try to apply the operation to all heads, but may only work
* for *disabling* 10 bpc mode, not for enabling it -- Mostly useful for a master reset to
* system default, e.g., as part of error handling or Screen shutdown handling.
* 'enable' True = Enable ABGR2101010 support, False = Disable ARGB2101010 support, reenable ARGB8888 support.
*
*/
psych_bool PsychEnableNative10BitFramebuffer(PsychWindowRecordType* windowRecord, psych_bool enable)
{
#if PSYCH_SYSTEM == PSYCH_OSX || PSYCH_SYSTEM == PSYCH_LINUX
int i, si, ei, headid, headiter, screenId;
unsigned int lutreg, ctlreg, value, status;
int gpuMaintype, gpuMinortype;
// Child protection:
if (windowRecord && !PsychIsOnscreenWindow(windowRecord)) PsychErrorExitMsg(PsychError_internal, "Invalid non-onscreen windowRecord provided!!!");
// Either screenid from windowRecord or our special -1 "all Screens" Id:
screenId = (windowRecord) ? windowRecord->screenNumber : -1;
// We only support Radeon GPU's, nothing else:
if (!PsychGetGPUSpecs(screenId, &gpuMaintype, &gpuMinortype, NULL, NULL) ||
(gpuMaintype != kPsychRadeon) || (gpuMinortype >= 0xffff)) {
return(FALSE);
}
// Define range of screens: Either a single specific one, or all:
si = (screenId!=-1) ? screenId : 0;
ei = (screenId!=-1) ? screenId+1 : PsychGetNumDisplays();
// Loop over all target screens:
for (i = si; i < ei; i++) {
// Iterate over range of all assigned heads for this screenId 'i' and reconfigure them:
for (headiter = 0; headiter < kPsychMaxPossibleCrtcs; headiter++) {
// Map screenid to headid for headiter'th head:
headid = PsychScreenToCrtcId(i, headiter);
// We're done as soon as we encounter invalid negative headid.
if (headid < 0) break;
// Select Radeon HW registers for corresponding heads:
if (gpuMinortype < 0x40) {
// DCE-3 and earlier:
lutreg = (headid == 0) ? RADEON_D1GRPH_LUT_SEL : RADEON_D2GRPH_LUT_SEL;
ctlreg = (headid == 0) ? RADEON_D1GRPH_CONTROL : RADEON_D2GRPH_CONTROL;
}
else {
// DCE-4 and later:
if (headid > DCE4_MAXHEADID) {
printf("PTB-ERROR: Invalid headId %i (greater than max %i) provided for DCE-4+ display engine!\n", headid, DCE4_MAXHEADID);
return(false);
}
lutreg = EVERGREEN_DC_LUT_10BIT_BYPASS + crtcoff[headid];
ctlreg = EVERGREEN_GRPH_CONTROL + crtcoff[headid];
}
// Enable or Disable?
if (enable) {
// Enable:
// Switch hardware LUT's to bypass mode:
// We set bit 8 to enable "bypass LUT in 2101010 mode":
value = PsychOSKDReadRegister(screenId, lutreg, &status);
if (status) {
printf("PTB-ERROR: Failed to set 10 bit framebuffer mode (LUTReg read failed).\n");
return(false);
}
// Set the bypass bit:
value = value | 0x1 << 8;
PsychOSKDWriteRegister(screenId, lutreg, value, &status);
if (status) {
printf("PTB-ERROR: Failed to set 10 bit framebuffer mode (LUTReg write failed).\n");
return(false);
}
// Only reconfigure framebuffer scanout if this is really our true Native10bpc hack:
// This is usually skipped on FireGL/FirePro GPU's as their drivers do it already...
if (windowRecord->specialflags & kPsychNative10bpcFBActive) {
// Switch CRTC to ABGR2101010 readout mode:
// We set bit 8 to enable that mode:
value = PsychOSKDReadRegister(screenId, ctlreg, &status);
if (status) {
printf("PTB-ERROR: Failed to set 10 bit framebuffer mode (CTLReg read failed).\n");
return(false);
}
// Set 2101010 mode bit:
value = value | 0x1 << 8;
PsychOSKDWriteRegister(screenId, ctlreg, value, &status);
if (status) {
printf("PTB-ERROR: Failed to set 10 bit framebuffer mode (CTLReg write failed).\n");
return(false);
}
}
// Pipe should be in 10 bpc mode now...
if (PsychPrefStateGet_Verbosity() > 2) printf("PTB-INFO: System framebuffer switched to ARGB2101010 mode for screen %i [head %i].\n", i, headid);
} else {
// Disable:
// Only reconfigure framebuffer scanout if this is really our true Native10bpc hack:
// This is usually skipped on FireGL/FirePro GPU's as their drivers do it already...
if (windowRecord->specialflags & kPsychNative10bpcFBActive) {
// Switch CRTC to ABGR8888 readout mode:
// We clear bit 8 to enable that mode:
value = PsychOSKDReadRegister(screenId, ctlreg, &status);
if (status) {
// This codepath gets always called in PsychCloseWindow(), so we should skip it
// silently if register read fails, as this is expected on MS-Windows and on all
// non-Radeon hardware and if kernel driver isn't loaded:
if (PsychPrefStateGet_Verbosity() > 5) printf("PTB-ERROR: Failed to set 8 bit framebuffer mode (CTLReg read failed).\n");
return(false);
}
else if (PsychPrefStateGet_Verbosity() > 5) printf("PTB-DEBUG: In disable 10bpc: Readreg. ctlreg yields %lx\n", value);
// Clear 2101010 mode bit:
value = value & ~(0x1 << 8);
PsychOSKDWriteRegister(screenId, ctlreg, value, &status);
if (status) {
printf("PTB-ERROR: Failed to set 8 bit framebuffer mode (CTLReg write failed).\n");
return(false);
}
else if (PsychPrefStateGet_Verbosity() > 5) printf("PTB-DEBUG: In disable 10bpc: ctlreg reset\n");
// Wait 500 msecs for GPU to settle:
PsychWaitIntervalSeconds(0.5);
}
// Switch hardware LUT's to standard mapping mode:
// We clear bit 8 to disable "bypass LUT in 2101010 mode":
value = PsychOSKDReadRegister(screenId, lutreg, &status);
if (status) {
printf("PTB-ERROR: Failed to set 8 bit framebuffer mode (LUTReg read failed).\n");
return(false);
}
else if (PsychPrefStateGet_Verbosity() > 5) printf("PTB-DEBUG: In disable 10bpc: Readreg. lutreg yields %lx\n", value);
// Clear LUT bypass bit:
value = value & ~(0x1 << 8);
PsychOSKDWriteRegister(screenId, lutreg, value, &status);
if (status) {
printf("PTB-ERROR: Failed to set 8 bit framebuffer mode (LUTReg write failed).\n");
return(false);
}
else if (PsychPrefStateGet_Verbosity() > 5) printf("PTB-DEBUG: In disable 10bpc: lutreg reset\n");
// Pipe should be in 8 bpc mode now...
if (PsychPrefStateGet_Verbosity() > 2) printf("PTB-INFO: System framebuffer switched to standard ARGB8888 mode for screen %i [head %i].\n", i, headid);
}
} // Next display head...
} // Next screenId.
// Done.
return(TRUE);
#else
// This cool stuff not supported on the uncool Windows OS:
return(FALSE);
#endif
}
/* PsychSetGPUIdentityPassthrough() - Control identity passthrough of framebuffer 8 bpc pixel values to encoders/connectors:
*
* This function enables or disables bit depths truncation or dithering of digital display output ports of supported
* graphics hardware, and optionally loads a identity LUT into the hardware and configures other parts of the GPU's
* color management for untampered passthrough of framebuffer pixels.
* Currently the ATI Radeon X1000/HD2000/HD3000/HD4000/HD5000/HD6000 and later cards should allow this.
*
* This needs support from the Psychtoolbox kernel level support driver for low-level register reads
* and writes to the GPU registers.
*
*
* 'windowRecord' Is used to find the Id of the screen for which mode should be changed. If set to NULL then...
* 'screenId' ... is used to determine the screenId for the screen. Otherwise 'screenId' is ignored.
* 'passthroughEnable' Zero = Disable passthrough: Currently only reenables dithering, otherwise a no-op.
* 1 = Enable passthrough, if possible.
* 'changeDithering' FALSE = Don't touch dither control, TRUE = Control dithering enable/disable if possible.
*
* Returns:
*
* 0xffffffff if feature unsupported by given OS/Driver/GPU combo.
* 0 = On failure to establish passthrough.
* 1 = On partial success: Dithering disabled and identityt LUT loaded, but other GPU color transformation
* features may not be configured optimally for passthrough.
* 2 = On full success, as far as can be determined by software.
*
*/
unsigned int PsychSetGPUIdentityPassthrough(PsychWindowRecordType* windowRecord, int screenId, psych_bool passthroughEnable, psych_bool changeDithering)
{
#if PSYCH_SYSTEM == PSYCH_OSX || PSYCH_SYSTEM == PSYCH_LINUX
unsigned int rc, rcret;
int head, iter;
// Init return code to "unsupported":
rcret = 0xffffffff;
// Child protection:
if (windowRecord && !PsychIsOnscreenWindow(windowRecord)) PsychErrorExitMsg(PsychError_internal, "Invalid non-onscreen windowRecord provided!!!");
// Either screenid from windowRecord or as passed in:
if (windowRecord) screenId = windowRecord->screenNumber;
// Check if kernel driver is enabled, otherwise this won't work:
if (!PsychOSIsKernelDriverAvailable(screenId)) {
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: GPU framebuffer passthrough setup requested, but this is not supported without kernel driver.\n");
return(0xffffffff);
}
// Try to enable or disable dithering on display:
if (changeDithering) PsychSetOutputDithering(windowRecord, screenId, (passthroughEnable) ? 0 : 1);
// We're done if this an actual passthrough disable, as a full disable isn't yet implemented:
if (!passthroughEnable) return(0);
// Start with head undefined:
head = -1;
for (iter = 0; iter < kPsychMaxPossibleCrtcs; iter++) {
if (screenId >= 0) {
// Positive screenId: Apply to all crtc's for this screenId:
// Is there an iter'th crtc assigned to this screen?
head = PsychScreenToCrtcId(screenId, iter);
// If end of list of associated crtc's for this screenId reached, then we're done:
if (head < 0) break;
}
else {
// Negative screenId -> Only affect one head defined by screenId:
if (head < 0) {
// Setup single target head in this iteration:
head = -screenId;
}
else {
// Single target head already set up: We're done:
break;
}
}
// Check if remaining GPU is already configured for untampered identity passthrough:
rc = PsychOSKDGetLUTState(screenId, head, (PsychPrefStateGet_Verbosity() > 4) ? 1 : 0);
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: [screen %i, head %i] 1st LUT query rc = %i.\n", screenId, head, rc);
if (rc == 0xffffffff) {
// Unsupported for this GPU. We're done:
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: GPU framebuffer passthrough setup on screenid %i, head %i requested, but this is not supported on this GPU.\n", screenId, head);
rcret = 0xffffffff;
continue;
}
// Perfect identity passthrough already configured?
if (rc == 2) {
// Yes. We're successfully done!
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: GPU framebuffer passthrough setup I completed on screenid %i, head %i. Perfect passthrough should work now.\n", screenId, head);
rcret = 2;
continue;
}
// No. Try to setup GPU for passthrough:
if (!PsychOSKDLoadIdentityLUT(screenId, head)) {
// Failed.
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: GPU framebuffer passthrough setup requested on screenid %i, head %i, but setup failed.\n", screenId, head);
rcret = 0xffffffff;
continue;
}
// Make sure, GPU's gamma table can settle by waiting 250 msecs:
PsychYieldIntervalSeconds(0.250);
// Setup supposedly successfully finished. Re-Query state:
rc = PsychOSKDGetLUTState(screenId, head, (PsychPrefStateGet_Verbosity() > 4) ? 1 : 0);
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: [screen %i, head %i] 2nd LUT query rc = %i.\n", screenId, head, rc);
// Perfect identity passthrough now configured?
if (rc == 2) {
// Yes. We're successfully done!
if(PsychPrefStateGet_Verbosity() > 3) printf("PTB-INFO: GPU framebuffer passthrough setup II completed on screenid %i, head %i. Perfect passthrough should work now.\n", screenId, head);
rcret = 2;
continue;
}
if (rc == 3) {
// Not quite. We've done what we could. A perfect identity LUT is setup, but the rest of the hw
// isn't in that a great shape. This may or may not be good enough...
if(PsychPrefStateGet_Verbosity() > 3) {
printf("PTB-INFO: GPU framebuffer passthrough setup II completed on screenid %i, head %i. Sort of ok passthrough achieved. May or may not work.\n", screenId, head);
printf("PTB-INFO: A perfect identity gamma table is loaded, but the other GPU color transformation settings are still suboptimal.\n");
}
rcret = 1;
continue;
}
// Ok, we failed.
if(PsychPrefStateGet_Verbosity() > 3) {
printf("PTB-INFO: GPU framebuffer passthrough setup II completed on screenid %i, head %i. Failed to establish identity passthrough!\n", screenId, head);
printf("PTB-INFO: Could not upload a perfect identity LUT. May still work due to hopefully disabled dithering, who knows?\n");
}
rcret = 0;
}
return(rcret);
#else
// This cool stuff not supported on the uncool Windows OS:
if(PsychPrefStateGet_Verbosity() > 4) printf("PTB-INFO: GPU framebuffer passthrough setup requested, but this is not supported on MS-Windows.\n");
return(0xffffffff);
#endif
}
