Initial work on spectrometer integration. Fixed bug causing textures …

…to have weird color space conversions when moving from sRGB to linear. Fixes #656.

src/ngscopeclient/MainWindow.cpp

@@ -155,6 +155,8 @@ MainWindow::MainWindow(shared_ptr<QueueHandle> queue)
 	LoadToolbarIcons();
 	LoadGradients();
 	m_texmgr.LoadTexture("warning", FindDataFile("icons/48x48/dialog-warning-2.png"));
+	m_texmgr.LoadTexture("visible-spectrum-380nm-750nm",
+		FindDataFile("icons/gradients/visible-spectrum-380nm-750nm.png"));
 
 	//Don't move windows when dragging in the body, only the title bar
 	ImGui::GetIO().ConfigWindowsMoveFromTitleBarOnly = true;

src/ngscopeclient/TextureManager.cpp

@@ -118,7 +118,7 @@ Texture::Texture(
 		{},
 		*m_image,
 		vk::ImageViewType::e2D,
-		vk::Format::eR8G8B8A8Srgb,
+		vk::Format::eR8G8B8A8Unorm,
 		{},
 		vk::ImageSubresourceRange(vk::ImageAspectFlagBits::eColor, 0, 1, 0, 1)
 		);
@@ -392,8 +392,10 @@ void TextureManager::LoadTexture(
 		fclose(fp);
 		return;
 	}
+	int bytesPerComponent = 1;
+	int bytesPerPixel = 4*bytesPerComponent;
 	LogTrace("Image is %d x %d pixels, RGBA8888\n", width, height);
-	VkDeviceSize size = width * height * 4;
+	VkDeviceSize size = width * height * bytesPerPixel;
 
 	//Allocate temporary staging buffer
 	vk::BufferCreateInfo bufinfo({}, size, vk::BufferUsageFlagBits::eTransferSrc);
@@ -426,7 +428,7 @@ void TextureManager::LoadTexture(
 	stagingBuf.bindMemory(*physMem, 0);
 
 	//Fill the mapped buffer with image data from the PNG
-	size_t rowSize = width * 4;
+	size_t rowSize = width * bytesPerPixel;
 	for(int y=0; y<height; y++)
 		memcpy(mappedPtr + (y*rowSize), rowPtrs[y], rowSize);
 	physMem.unmapMemory();
@@ -435,7 +437,7 @@ void TextureManager::LoadTexture(
 	vk::ImageCreateInfo imageInfo(
 		{},
 		vk::ImageType::e2D,
-		vk::Format::eR8G8B8A8Srgb,
+		vk::Format::eR8G8B8A8Unorm,
 		vk::Extent3D(width, height, 1),
 		1,
 		1,

src/ngscopeclient/TimebasePropertiesDialog.h

@@ -1,8 +1,8 @@
 /***********************************************************************************************************************
 *                                                                                                                      *
-* glscopeclient                                                                                                        *
+* ngscopeclient                                                                                                        *
 *                                                                                                                      *
-* Copyright (c) 2012-2022 Andrew D. Zonenberg                                                                          *
+* Copyright (c) 2012-2023 Andrew D. Zonenberg                                                                          *
 * All rights reserved.                                                                                                 *
 *                                                                                                                      *
 * Redistribution and use in source and binary forms, with or without modification, are permitted provided that the     *

src/ngscopeclient/VulkanWindow.cpp

@@ -316,9 +316,7 @@ bool VulkanWindow::UpdateFramebuffer()
 	const VkFormat requestSurfaceImageFormat[] =
 	{
 		VK_FORMAT_B8G8R8A8_UNORM,
-		VK_FORMAT_R8G8B8A8_UNORM,
-		VK_FORMAT_B8G8R8_UNORM,
-		VK_FORMAT_R8G8B8_UNORM
+		VK_FORMAT_R8G8B8A8_UNORM
 	};
 	const VkColorSpaceKHR requestSurfaceColorSpace = VK_COLORSPACE_SRGB_NONLINEAR_KHR;
 	auto format = ImGui_ImplVulkanH_SelectSurfaceFormat(

src/ngscopeclient/WaveformArea.cpp

@@ -2003,6 +2003,17 @@ void WaveformArea::RenderBackgroundGradient(ImVec2 start, ImVec2 size)
 		color_top,
 		color_bottom,
 		color_bottom);
+
+	//TODO: add preference or per-area setting for this
+	//For now, always draw if X axis units are distance/wavelength
+	if(m_group->GetXAxisUnit() == Unit::UNIT_PM)
+	{
+		//Visible spectrum texture covers 380 - 750 nm
+		draw_list->AddImage(
+			m_parent->GetTextureManager()->GetTexture("visible-spectrum-380nm-750nm"),
+			ImVec2(m_group->XAxisUnitsToXPosition(380000), start.y),
+			ImVec2(m_group->XAxisUnitsToXPosition(750000), start.y + size.y));
+	}
 }
 
 /**