PickPixel's x and y parameters should be mip-relative

* Previously x and y always ranged from 0,0 to width-1,height-1. Even for lower
  mips, the value was just effectively shifted.
* This is quite unclear at the API level so instead x and y are now relative to
  the selected mip's dimensions.

qrenderdoc/Windows/TextureViewer.cpp

@@ -736,6 +736,9 @@ void TextureViewer::RT_FetchCurrentPixel(uint32_t x, uint32_t y, PixelValue &pic
   if(m_TexDisplay.flipY)
     y = (texptr->height - 1) - y;
 
+  x = qMax(0U, x >> m_TexDisplay.mip);
+  y = qMax(0U, y >> m_TexDisplay.mip);
+
   pickValue = m_Output->PickPixel(m_TexDisplay.resourceId, true, x, y, m_TexDisplay.sliceFace,
                                   m_TexDisplay.mip, m_TexDisplay.sampleIdx);
 

renderdoc/driver/d3d11/d3d11_replay.cpp

@@ -3160,8 +3160,8 @@ void D3D11Replay::PickPixel(ResourceId texture, uint32_t x, uint32_t y, uint32_t
     texDisplay.resourceId = texture;
     texDisplay.typeHint = typeHint;
     texDisplay.rawOutput = true;
-    texDisplay.xOffset = -float(x);
-    texDisplay.yOffset = -float(y);
+    texDisplay.xOffset = -float(x << mip);
+    texDisplay.yOffset = -float(y << mip);
 
     RenderTextureInternal(texDisplay, false);
   }

renderdoc/driver/d3d12/d3d12_replay.cpp

@@ -1720,8 +1720,8 @@ void D3D12Replay::PickPixel(ResourceId texture, uint32_t x, uint32_t y, uint32_t
     texDisplay.resourceId = texture;
     texDisplay.typeHint = typeHint;
     texDisplay.rawOutput = true;
-    texDisplay.xOffset = -float(x);
-    texDisplay.yOffset = -float(y);
+    texDisplay.xOffset = -float(x << mip);
+    texDisplay.yOffset = -float(y << mip);
 
     RenderTextureInternal(GetDebugManager()->GetCPUHandle(PICK_PIXEL_RTV), texDisplay,
                           eTexDisplay_F32Render);

renderdoc/driver/gl/gl_debug.cpp

@@ -2361,8 +2361,8 @@ void GLReplay::PickPixel(ResourceId texture, uint32_t x, uint32_t y, uint32_t sl
   texDisplay.resourceId = texture;
   texDisplay.typeHint = typeHint;
   texDisplay.rawOutput = true;
-  texDisplay.xOffset = -float(x);
-  texDisplay.yOffset = -float(y);
+  texDisplay.xOffset = -float(x << mip);
+  texDisplay.yOffset = -float(y << mip);
 
   RenderTextureInternal(texDisplay, eTexDisplay_MipShift);
 

renderdoc/driver/vulkan/vk_replay.cpp

@@ -752,8 +752,8 @@ void VulkanReplay::PickPixel(ResourceId texture, uint32_t x, uint32_t y, uint32_
       texDisplay.resourceId = texture;
       texDisplay.typeHint = typeHint;
       texDisplay.rawOutput = true;
-      texDisplay.xOffset = -float(x);
-      texDisplay.yOffset = -float(y);
+      texDisplay.xOffset = -float(x << mip);
+      texDisplay.yOffset = -float(y << mip);
 
       // only render green (stencil) in second pass
       if(pass == 1)