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-rw-r--r--LibOVR/Src/Util/Util_Render_Stereo.cpp625
1 files changed, 314 insertions, 311 deletions
diff --git a/LibOVR/Src/Util/Util_Render_Stereo.cpp b/LibOVR/Src/Util/Util_Render_Stereo.cpp
index 8986e30..b16cfb5 100644
--- a/LibOVR/Src/Util/Util_Render_Stereo.cpp
+++ b/LibOVR/Src/Util/Util_Render_Stereo.cpp
@@ -1,311 +1,314 @@
-/************************************************************************************
-
-Filename : Util_Render_Stereo.cpp
-Content : Stereo rendering configuration implementation
-Created : October 22, 2012
-Authors : Michael Antonov, Andrew Reisse
-
-Copyright : Copyright 2012 Oculus, Inc. All Rights reserved.
-
-Use of this software is subject to the terms of the Oculus Inc license
-agreement provided at the time of installation or download, or which
-otherwise accompanies this software in either electronic or hard copy form.
-
-*************************************************************************************/
-
-#include "Util_Render_Stereo.h"
-
-namespace OVR { namespace Util { namespace Render {
-
-
-//-----------------------------------------------------------------------------------
-
-// DistortionFnInverse computes the inverse of the distortion function on an argument.
-float DistortionConfig::DistortionFnInverse(float r)
-{
- OVR_ASSERT((r <= 10.0f));
-
- float s, d;
- float delta = r * 0.25f;
-
- s = r * 0.5f;
- d = fabs(r - DistortionFn(s));
-
- for (int i = 0; i < 20; i++)
- {
- float sUp = s + delta;
- float sDown = s - delta;
- float dUp = fabs(r - DistortionFn(sUp));
- float dDown = fabs(r - DistortionFn(sDown));
-
- if (dUp < d)
- {
- s = sUp;
- d = dUp;
- }
- else if (dDown < d)
- {
- s = sDown;
- d = dDown;
- }
- else
- {
- delta *= 0.5f;
- }
- }
-
- return s;
-}
-
-
-//-----------------------------------------------------------------------------------
-// **** StereoConfig Implementation
-
-StereoConfig::StereoConfig(StereoMode mode, const Viewport& vp)
- : Mode(mode),
- InterpupillaryDistance(0.064f), AspectMultiplier(1.0f),
- FullView(vp), DirtyFlag(true),
- YFov(0), Aspect(vp.w / float(vp.h)), ProjectionCenterOffset(0),
- OrthoPixelOffset(0)
-{
- // And default distortion for it.
- Distortion.SetCoefficients(1.0f, 0.22f, 0.24f);
- Distortion.Scale = 1.0f; // Will be computed later.
-
- // Fit left of the image.
- DistortionFitX = -1.0f;
- DistortionFitY = 0.0f;
-
- // Initialize "fake" default HMD values for testing without HMD plugged in.
- // These default values match those returned by the HMD.
- HMD.HResolution = 1280;
- HMD.VResolution = 800;
- HMD.HScreenSize = 0.14976f;
- HMD.VScreenSize = HMD.HScreenSize / (1280.0f / 800.0f);
- HMD.InterpupillaryDistance = InterpupillaryDistance;
- HMD.LensSeparationDistance = 0.0635f;
- HMD.EyeToScreenDistance = 0.041f;
- HMD.DistortionK[0] = Distortion.K[0];
- HMD.DistortionK[1] = Distortion.K[1];
- HMD.DistortionK[2] = Distortion.K[2];
- HMD.DistortionK[3] = 0;
-
- Set2DAreaFov(DegreeToRad(85.0f));
-}
-
-void StereoConfig::SetFullViewport(const Viewport& vp)
-{
- if (vp != FullView)
- {
- FullView = vp;
- DirtyFlag = true;
- }
-}
-
-void StereoConfig::SetHMDInfo(const HMDInfo& hmd)
-{
- HMD = hmd;
- Distortion.K[0] = hmd.DistortionK[0];
- Distortion.K[1] = hmd.DistortionK[1];
- Distortion.K[2] = hmd.DistortionK[2];
- Distortion.K[3] = hmd.DistortionK[3];
-
- Distortion.SetChromaticAberration(hmd.ChromaAbCorrection[0], hmd.ChromaAbCorrection[1],
- hmd.ChromaAbCorrection[2], hmd.ChromaAbCorrection[3]);
-
- DirtyFlag = true;
-}
-
-void StereoConfig::SetDistortionFitPointVP(float x, float y)
-{
- DistortionFitX = x;
- DistortionFitY = y;
- DirtyFlag = true;
-}
-
-void StereoConfig::SetDistortionFitPointPixels(float x, float y)
-{
- DistortionFitX = (4 * x / float(FullView.w)) - 1.0f;
- DistortionFitY = (2 * y / float(FullView.h)) - 1.0f;
- DirtyFlag = true;
-}
-
-void StereoConfig::Set2DAreaFov(float fovRadians)
-{
- Area2DFov = fovRadians;
- DirtyFlag = true;
-}
-
-
-const StereoEyeParams& StereoConfig::GetEyeRenderParams(StereoEye eye)
-{
- static const UByte eyeParamIndices[3] = { 0, 0, 1 };
-
- updateIfDirty();
- OVR_ASSERT(eye < sizeof(eyeParamIndices));
- return EyeRenderParams[eyeParamIndices[eye]];
-}
-
-
-void StereoConfig::updateComputedState()
-{
- // Need to compute all of the following:
- // - Aspect Ratio
- // - FOV
- // - Projection offsets for 3D
- // - Distortion XCenterOffset
- // - Update 2D
- // - Initialize EyeRenderParams
-
- // Compute aspect ratio. Stereo mode cuts width in half.
- Aspect = float(FullView.w) / float(FullView.h);
- Aspect *= (Mode == Stereo_None) ? 1.0f : 0.5f;
- Aspect *= AspectMultiplier;
-
- updateDistortionOffsetAndScale();
-
- // Compute Vertical FOV based on distance, distortion, etc.
- // Distance from vertical center to render vertical edge perceived through the lens.
- // This will be larger then normal screen size due to magnification & distortion.
- //
- // This percievedHalfRTDistance equation should hold as long as the render target
- // and display have the same aspect ratios. What we'd like to know is where the edge
- // of the render target will on the perceived screen surface. With NO LENS,
- // the answer would be:
- //
- // halfRTDistance = (VScreenSize / 2) * aspect *
- // DistortionFn_Inverse( DistortionScale / aspect )
- //
- // To model the optical lens we eliminates DistortionFn_Inverse. Aspect ratios
- // cancel out, so we get:
- //
- // halfRTDistance = (VScreenSize / 2) * DistortionScale
- //
- if (Mode == Stereo_None)
- {
- YFov = DegreeToRad(80.0f);
- }
- else
- {
- float percievedHalfRTDistance = (HMD.VScreenSize / 2) * Distortion.Scale;
- YFov = 2.0f * atan(percievedHalfRTDistance/HMD.EyeToScreenDistance);
- }
-
- updateProjectionOffset();
- update2D();
- updateEyeParams();
-
- DirtyFlag = false;
-}
-
-void StereoConfig::updateDistortionOffsetAndScale()
-{
- // Distortion center shift is stored separately, since it isn't affected
- // by the eye distance.
- float lensOffset = HMD.LensSeparationDistance * 0.5f;
- float lensShift = HMD.HScreenSize * 0.25f - lensOffset;
- float lensViewportShift = 4.0f * lensShift / HMD.HScreenSize;
- Distortion.XCenterOffset= lensViewportShift;
-
- // Compute distortion scale from DistortionFitX & DistortionFitY.
- // Fit value of 0.0 means "no fit".
- if ((fabs(DistortionFitX) < 0.0001f) && (fabs(DistortionFitY) < 0.0001f))
- {
- Distortion.Scale = 1.0f;
- }
- else
- {
- // Convert fit value to distortion-centered coordinates before fit radius
- // calculation.
- float stereoAspect = 0.5f * float(FullView.w) / float(FullView.h);
- float dx = DistortionFitX - Distortion.XCenterOffset;
- float dy = DistortionFitY / stereoAspect;
- float fitRadius = sqrt(dx * dx + dy * dy);
- Distortion.Scale = Distortion.DistortionFn(fitRadius)/fitRadius;
- }
-}
-
-void StereoConfig::updateProjectionOffset()
-{
- // Post-projection viewport coordinates range from (-1.0, 1.0), with the
- // center of the left viewport falling at (1/4) of horizontal screen size.
- // We need to shift this projection center to match with the lens center;
- // note that we don't use the IPD here due to collimated light property of the lens.
- // We compute this shift in physical units (meters) to
- // correct for different screen sizes and then rescale to viewport coordinates.
- float viewCenter = HMD.HScreenSize * 0.25f;
- float eyeProjectionShift = viewCenter - HMD.LensSeparationDistance*0.5f;
- ProjectionCenterOffset = 4.0f * eyeProjectionShift / HMD.HScreenSize;
-}
-
-void StereoConfig::update2D()
-{
- // Orthographic projection fakes a screen at a distance of 0.8m from the
- // eye, where hmd screen projection surface is at 0.05m distance.
- // This introduces an extra off-center pixel projection shift based on eye distance.
- // This offCenterShift is the pixel offset of the other camera's center
- // in your reference camera based on surface distance.
- float metersToPixels = (HMD.HResolution / HMD.HScreenSize);
- float lensDistanceScreenPixels= metersToPixels * HMD.LensSeparationDistance;
- float eyeDistanceScreenPixels = metersToPixels * InterpupillaryDistance;
- float offCenterShiftPixels = (HMD.EyeToScreenDistance / 0.8f) * eyeDistanceScreenPixels;
- float leftPixelCenter = (HMD.HResolution / 2) - lensDistanceScreenPixels * 0.5f;
- float rightPixelCenter = lensDistanceScreenPixels * 0.5f;
- float pixelDifference = leftPixelCenter - rightPixelCenter;
-
- // This computes the number of pixels that fit within specified 2D FOV (assuming
- // distortion scaling will be done).
- float percievedHalfScreenDistance = tan(Area2DFov * 0.5f) * HMD.EyeToScreenDistance;
- float vfovSize = 2.0f * percievedHalfScreenDistance / Distortion.Scale;
- FovPixels = HMD.VResolution * vfovSize / HMD.VScreenSize;
-
- // Create orthographic matrix.
- Matrix4f& m = OrthoCenter;
- m.SetIdentity();
- m.M[0][0] = FovPixels / (FullView.w * 0.5f);
- m.M[1][1] = -FovPixels / FullView.h;
- m.M[0][3] = 0;
- m.M[1][3] = 0;
- m.M[2][2] = 0;
-
- float orthoPixelOffset = (pixelDifference + offCenterShiftPixels/Distortion.Scale) * 0.5f;
- OrthoPixelOffset = orthoPixelOffset * 2.0f / FovPixels;
-}
-
-void StereoConfig::updateEyeParams()
-{
- // Projection matrix for the center eye, which the left/right matrices are based on.
- Matrix4f projCenter = Matrix4f::PerspectiveRH(YFov, Aspect, 0.01f, 1000.0f);
-
- switch(Mode)
- {
- case Stereo_None:
- {
- EyeRenderParams[0].Init(StereoEye_Center, FullView, 0, projCenter, OrthoCenter);
- }
- break;
-
- case Stereo_LeftRight_Multipass:
- {
- Matrix4f projLeft = Matrix4f::Translation(ProjectionCenterOffset, 0, 0) * projCenter,
- projRight = Matrix4f::Translation(-ProjectionCenterOffset, 0, 0) * projCenter;
-
- EyeRenderParams[0].Init(StereoEye_Left,
- Viewport(FullView.x, FullView.y, FullView.w/2, FullView.h),
- +InterpupillaryDistance * 0.5f, // World view shift.
- projLeft, OrthoCenter * Matrix4f::Translation(OrthoPixelOffset, 0, 0),
- &Distortion);
- EyeRenderParams[1].Init(StereoEye_Right,
- Viewport(FullView.x + FullView.w/2, FullView.y, FullView.w/2, FullView.h),
- -InterpupillaryDistance * 0.5f,
- projRight, OrthoCenter * Matrix4f::Translation(-OrthoPixelOffset, 0, 0),
- &Distortion);
- }
- break;
- }
-
-}
-
-
-}}} // OVR::Util::Render
-
+/************************************************************************************
+
+Filename : Util_Render_Stereo.cpp
+Content : Stereo rendering configuration implementation
+Created : October 22, 2012
+Authors : Michael Antonov, Andrew Reisse
+
+Copyright : Copyright 2012 Oculus, Inc. All Rights reserved.
+
+Use of this software is subject to the terms of the Oculus Inc license
+agreement provided at the time of installation or download, or which
+otherwise accompanies this software in either electronic or hard copy form.
+
+*************************************************************************************/
+
+#include "Util_Render_Stereo.h"
+
+namespace OVR { namespace Util { namespace Render {
+
+
+//-----------------------------------------------------------------------------------
+
+// DistortionFnInverse computes the inverse of the distortion function on an argument.
+float DistortionConfig::DistortionFnInverse(float r)
+{
+ OVR_ASSERT((r <= 10.0f));
+
+ float s, d;
+ float delta = r * 0.25f;
+
+ s = r * 0.5f;
+ d = fabs(r - DistortionFn(s));
+
+ for (int i = 0; i < 20; i++)
+ {
+ float sUp = s + delta;
+ float sDown = s - delta;
+ float dUp = fabs(r - DistortionFn(sUp));
+ float dDown = fabs(r - DistortionFn(sDown));
+
+ if (dUp < d)
+ {
+ s = sUp;
+ d = dUp;
+ }
+ else if (dDown < d)
+ {
+ s = sDown;
+ d = dDown;
+ }
+ else
+ {
+ delta *= 0.5f;
+ }
+ }
+
+ return s;
+}
+
+
+//-----------------------------------------------------------------------------------
+// **** StereoConfig Implementation
+
+StereoConfig::StereoConfig(StereoMode mode, const Viewport& vp)
+ : Mode(mode),
+ InterpupillaryDistance(0.064f), AspectMultiplier(1.0f),
+ FullView(vp), DirtyFlag(true), IPDOverride(false),
+ YFov(0), Aspect(vp.w / float(vp.h)), ProjectionCenterOffset(0),
+ OrthoPixelOffset(0)
+{
+ // And default distortion for it.
+ Distortion.SetCoefficients(1.0f, 0.22f, 0.24f);
+ Distortion.Scale = 1.0f; // Will be computed later.
+
+ // Fit left of the image.
+ DistortionFitX = -1.0f;
+ DistortionFitY = 0.0f;
+
+ // Initialize "fake" default HMD values for testing without HMD plugged in.
+ // These default values match those returned by the HMD.
+ HMD.HResolution = 1280;
+ HMD.VResolution = 800;
+ HMD.HScreenSize = 0.14976f;
+ HMD.VScreenSize = HMD.HScreenSize / (1280.0f / 800.0f);
+ HMD.InterpupillaryDistance = InterpupillaryDistance;
+ HMD.LensSeparationDistance = 0.0635f;
+ HMD.EyeToScreenDistance = 0.041f;
+ HMD.DistortionK[0] = Distortion.K[0];
+ HMD.DistortionK[1] = Distortion.K[1];
+ HMD.DistortionK[2] = Distortion.K[2];
+ HMD.DistortionK[3] = 0;
+
+ Set2DAreaFov(DegreeToRad(85.0f));
+}
+
+void StereoConfig::SetFullViewport(const Viewport& vp)
+{
+ if (vp != FullView)
+ {
+ FullView = vp;
+ DirtyFlag = true;
+ }
+}
+
+void StereoConfig::SetHMDInfo(const HMDInfo& hmd)
+{
+ HMD = hmd;
+ Distortion.K[0] = hmd.DistortionK[0];
+ Distortion.K[1] = hmd.DistortionK[1];
+ Distortion.K[2] = hmd.DistortionK[2];
+ Distortion.K[3] = hmd.DistortionK[3];
+
+ Distortion.SetChromaticAberration(hmd.ChromaAbCorrection[0], hmd.ChromaAbCorrection[1],
+ hmd.ChromaAbCorrection[2], hmd.ChromaAbCorrection[3]);
+
+ if (!IPDOverride)
+ InterpupillaryDistance = HMD.InterpupillaryDistance;
+
+ DirtyFlag = true;
+}
+
+void StereoConfig::SetDistortionFitPointVP(float x, float y)
+{
+ DistortionFitX = x;
+ DistortionFitY = y;
+ DirtyFlag = true;
+}
+
+void StereoConfig::SetDistortionFitPointPixels(float x, float y)
+{
+ DistortionFitX = (4 * x / float(FullView.w)) - 1.0f;
+ DistortionFitY = (2 * y / float(FullView.h)) - 1.0f;
+ DirtyFlag = true;
+}
+
+void StereoConfig::Set2DAreaFov(float fovRadians)
+{
+ Area2DFov = fovRadians;
+ DirtyFlag = true;
+}
+
+
+const StereoEyeParams& StereoConfig::GetEyeRenderParams(StereoEye eye)
+{
+ static const UByte eyeParamIndices[3] = { 0, 0, 1 };
+
+ updateIfDirty();
+ OVR_ASSERT(eye < sizeof(eyeParamIndices));
+ return EyeRenderParams[eyeParamIndices[eye]];
+}
+
+
+void StereoConfig::updateComputedState()
+{
+ // Need to compute all of the following:
+ // - Aspect Ratio
+ // - FOV
+ // - Projection offsets for 3D
+ // - Distortion XCenterOffset
+ // - Update 2D
+ // - Initialize EyeRenderParams
+
+ // Compute aspect ratio. Stereo mode cuts width in half.
+ Aspect = float(FullView.w) / float(FullView.h);
+ Aspect *= (Mode == Stereo_None) ? 1.0f : 0.5f;
+ Aspect *= AspectMultiplier;
+
+ updateDistortionOffsetAndScale();
+
+ // Compute Vertical FOV based on distance, distortion, etc.
+ // Distance from vertical center to render vertical edge perceived through the lens.
+ // This will be larger then normal screen size due to magnification & distortion.
+ //
+ // This percievedHalfRTDistance equation should hold as long as the render target
+ // and display have the same aspect ratios. What we'd like to know is where the edge
+ // of the render target will on the perceived screen surface. With NO LENS,
+ // the answer would be:
+ //
+ // halfRTDistance = (VScreenSize / 2) * aspect *
+ // DistortionFn_Inverse( DistortionScale / aspect )
+ //
+ // To model the optical lens we eliminates DistortionFn_Inverse. Aspect ratios
+ // cancel out, so we get:
+ //
+ // halfRTDistance = (VScreenSize / 2) * DistortionScale
+ //
+ if (Mode == Stereo_None)
+ {
+ YFov = DegreeToRad(80.0f);
+ }
+ else
+ {
+ float percievedHalfRTDistance = (HMD.VScreenSize / 2) * Distortion.Scale;
+ YFov = 2.0f * atan(percievedHalfRTDistance/HMD.EyeToScreenDistance);
+ }
+
+ updateProjectionOffset();
+ update2D();
+ updateEyeParams();
+
+ DirtyFlag = false;
+}
+
+void StereoConfig::updateDistortionOffsetAndScale()
+{
+ // Distortion center shift is stored separately, since it isn't affected
+ // by the eye distance.
+ float lensOffset = HMD.LensSeparationDistance * 0.5f;
+ float lensShift = HMD.HScreenSize * 0.25f - lensOffset;
+ float lensViewportShift = 4.0f * lensShift / HMD.HScreenSize;
+ Distortion.XCenterOffset= lensViewportShift;
+
+ // Compute distortion scale from DistortionFitX & DistortionFitY.
+ // Fit value of 0.0 means "no fit".
+ if ((fabs(DistortionFitX) < 0.0001f) && (fabs(DistortionFitY) < 0.0001f))
+ {
+ Distortion.Scale = 1.0f;
+ }
+ else
+ {
+ // Convert fit value to distortion-centered coordinates before fit radius
+ // calculation.
+ float stereoAspect = 0.5f * float(FullView.w) / float(FullView.h);
+ float dx = DistortionFitX - Distortion.XCenterOffset;
+ float dy = DistortionFitY / stereoAspect;
+ float fitRadius = sqrt(dx * dx + dy * dy);
+ Distortion.Scale = Distortion.DistortionFn(fitRadius)/fitRadius;
+ }
+}
+
+void StereoConfig::updateProjectionOffset()
+{
+ // Post-projection viewport coordinates range from (-1.0, 1.0), with the
+ // center of the left viewport falling at (1/4) of horizontal screen size.
+ // We need to shift this projection center to match with the lens center;
+ // note that we don't use the IPD here due to collimated light property of the lens.
+ // We compute this shift in physical units (meters) to
+ // correct for different screen sizes and then rescale to viewport coordinates.
+ float viewCenter = HMD.HScreenSize * 0.25f;
+ float eyeProjectionShift = viewCenter - HMD.LensSeparationDistance*0.5f;
+ ProjectionCenterOffset = 4.0f * eyeProjectionShift / HMD.HScreenSize;
+}
+
+void StereoConfig::update2D()
+{
+ // Orthographic projection fakes a screen at a distance of 0.8m from the
+ // eye, where hmd screen projection surface is at 0.05m distance.
+ // This introduces an extra off-center pixel projection shift based on eye distance.
+ // This offCenterShift is the pixel offset of the other camera's center
+ // in your reference camera based on surface distance.
+ float metersToPixels = (HMD.HResolution / HMD.HScreenSize);
+ float lensDistanceScreenPixels= metersToPixels * HMD.LensSeparationDistance;
+ float eyeDistanceScreenPixels = metersToPixels * InterpupillaryDistance;
+ float offCenterShiftPixels = (HMD.EyeToScreenDistance / 0.8f) * eyeDistanceScreenPixels;
+ float leftPixelCenter = (HMD.HResolution / 2) - lensDistanceScreenPixels * 0.5f;
+ float rightPixelCenter = lensDistanceScreenPixels * 0.5f;
+ float pixelDifference = leftPixelCenter - rightPixelCenter;
+
+ // This computes the number of pixels that fit within specified 2D FOV (assuming
+ // distortion scaling will be done).
+ float percievedHalfScreenDistance = tan(Area2DFov * 0.5f) * HMD.EyeToScreenDistance;
+ float vfovSize = 2.0f * percievedHalfScreenDistance / Distortion.Scale;
+ FovPixels = HMD.VResolution * vfovSize / HMD.VScreenSize;
+
+ // Create orthographic matrix.
+ Matrix4f& m = OrthoCenter;
+ m.SetIdentity();
+ m.M[0][0] = FovPixels / (FullView.w * 0.5f);
+ m.M[1][1] = -FovPixels / FullView.h;
+ m.M[0][3] = 0;
+ m.M[1][3] = 0;
+ m.M[2][2] = 0;
+
+ float orthoPixelOffset = (pixelDifference + offCenterShiftPixels/Distortion.Scale) * 0.5f;
+ OrthoPixelOffset = orthoPixelOffset * 2.0f / FovPixels;
+}
+
+void StereoConfig::updateEyeParams()
+{
+ // Projection matrix for the center eye, which the left/right matrices are based on.
+ Matrix4f projCenter = Matrix4f::PerspectiveRH(YFov, Aspect, 0.01f, 1000.0f);
+
+ switch(Mode)
+ {
+ case Stereo_None:
+ {
+ EyeRenderParams[0].Init(StereoEye_Center, FullView, 0, projCenter, OrthoCenter);
+ }
+ break;
+
+ case Stereo_LeftRight_Multipass:
+ {
+ Matrix4f projLeft = Matrix4f::Translation(ProjectionCenterOffset, 0, 0) * projCenter,
+ projRight = Matrix4f::Translation(-ProjectionCenterOffset, 0, 0) * projCenter;
+
+ EyeRenderParams[0].Init(StereoEye_Left,
+ Viewport(FullView.x, FullView.y, FullView.w/2, FullView.h),
+ +InterpupillaryDistance * 0.5f, // World view shift.
+ projLeft, OrthoCenter * Matrix4f::Translation(OrthoPixelOffset, 0, 0),
+ &Distortion);
+ EyeRenderParams[1].Init(StereoEye_Right,
+ Viewport(FullView.x + FullView.w/2, FullView.y, FullView.w/2, FullView.h),
+ -InterpupillaryDistance * 0.5f,
+ projRight, OrthoCenter * Matrix4f::Translation(-OrthoPixelOffset, 0, 0),
+ &Distortion);
+ }
+ break;
+ }
+
+}
+
+
+}}} // OVR::Util::Render
+
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