mxvk::VK_Text Class Reference

#include <mxvk/include/mxvk/mxvk_text.hpp>

Public Member Functions
void	clearCache ()
	Destroy all cached text textures, freeing GPU memory.
void	clearQueue ()
	Discard all pending text quads without rendering them.
bool	getTextDimensions (const std::string &text, int &width, int &height)
	Measure the pixel dimensions of a string with the current font.
bool	getTextDimensions (const std::string &text, int &width, int &height, const Font &textFont)
bool	getTextDimensions (const std::string &text, int &width, int &height, TTF_Font *textFont)
VK_Text &	operator= (const VK_Text &)=delete
VK_Text &	operator= (VK_Text &&)=delete
void	printTextG_Solid (const std::string &text, int x, int y, const SDL_Color &col)
	Queue a text string for solid (opaque) rendering.
void	printTextG_Solid (const std::string &text, int x, int y, const SDL_Color &col, const Font &textFont)
void	printTextG_Solid (const std::string &text, int x, int y, const SDL_Color &col, TTF_Font *textFont)
void	renderText (VkCommandBuffer cmdBuffer, VkPipelineLayout pipelineLayout, uint32_t screenWidth, uint32_t screenHeight)
	Record all queued text quads into a command buffer.
void	setDescriptorSetLayout (VkDescriptorSetLayout layout)
	Assign an external descriptor-set layout.
void	setFont (const std::string &fontPath, int fontSize)
	Change the active font.
	VK_Text (const VK_Text &)=delete
	VK_Text (VK_Text &&)=delete
	VK_Text (VkDevice device, VkPhysicalDevice physicalDevice, VkQueue graphicsQueue, VkCommandPool commandPool, const std::string &fontPath, int fontSize=24)
	Construct VKText and load the font.
	~VK_Text ()
	Destructor – destroys all Vulkan and SDL_ttf resources.

Public Attributes
VkSampler	fontSampler = VK_NULL_HANDLE
	Sampler used for all text textures.

Detailed Description

Definition at line 114 of file mxvk_text.hpp.

Constructor & Destructor Documentation

VK_Text() [1/3]

mxvk::VK_Text::VK_Text	(	VkDevice	device,
		VkPhysicalDevice	physicalDevice,
		VkQueue	graphicsQueue,
		VkCommandPool	commandPool,
		const std::string &	fontPath,
		int	fontSize = 24 )

Construct VKText and load the font.

Parameters

device	Logical device.
physicalDevice	Physical device.
graphicsQueue	Graphics queue.
commandPool	Command pool for staging.
fontPath	Path to the TTF font file.
fontSize	Point size.

Definition at line 71 of file mxvk_text.cpp.

        : device(dev), physicalDevice(physDev), graphicsQueue(gQueue), commandPool(cmdPool) {
 
        if (!TTF_Init()) {
            throw mxvk::Exception("Failed to initialize SDL_ttf: " + std::string(SDL_GetError()));
        }
 
        initFont(fontPath, fontSize);
    }

~VK_Text()

mxvk::VK_Text::~VK_Text

(

)

Destructor – destroys all Vulkan and SDL_ttf resources.

Definition at line 82 of file mxvk_text.cpp.

                      {
        vkDeviceWaitIdle(device);
        textQuads.clear();
        clearCache();
 
        if (descriptorPool != VK_NULL_HANDLE) {
            std::cout << "vk: destroying text descriptor pool\n";
            vkDestroyDescriptorPool(device, descriptorPool, nullptr);
        }
 
        if (fontSampler != VK_NULL_HANDLE) {
            std::cout << "vk: destroying text font sampler\n";
            vkDestroySampler(device, fontSampler, nullptr);
        }
 
        if (font) {
            std::cout << "mxvk: closing text font\n";
            TTF_CloseFont(font);
        }
        TTF_Quit();
    }

VK_Text() [2/3]

mxvk::VK_Text::VK_Text ( const VK_Text & )

delete

VK_Text() [3/3]

mxvk::VK_Text::VK_Text ( VK_Text && )

delete

Member Function Documentation

clearCache()

void mxvk::VK_Text::clearCache

(

)

Destroy all cached text textures, freeing GPU memory.

Definition at line 104 of file mxvk_text.cpp.

                             {
        for (auto &[key, cached] : textureCache) {
            destroyCachedTexture(cached);
        }
        textureCache.clear();
    }

clearQueue()

void mxvk::VK_Text::clearQueue

(

)

Discard all pending text quads without rendering them.

Definition at line 528 of file mxvk_text.cpp.

                             {
        if (textQuads.empty()) {
            return;
        }
        if (device == VK_NULL_HANDLE) {
            textQuads.clear();
            return;
        }
 
        // Text quads own vertex/index buffers referenced by submitted command buffers.
        // Wait for graphics work to finish before destroying these resources.
        const VkResult queue_idle_result = vkQueueWaitIdle(graphicsQueue);
        if (queue_idle_result == VK_ERROR_DEVICE_LOST) {
            std::cerr << "mxvk: Device lost while clearing queue; skipping text resource reset\n";
            textQuads.clear();
            return;
        }
        if (queue_idle_result != VK_SUCCESS) {
            throw mxvk::Exception(std::format(
                "Fatal : VkResult is \"{}\" in {} at line {}",
                static_cast<int>(queue_idle_result),
                __FILE__,
                __LINE__));
        }
 
        textQuads.clear();
        if (descriptorPool != VK_NULL_HANDLE) {
            VK_CHECK_RESULT(vkResetDescriptorPool(device, descriptorPool, 0));
        }
        pruneCache();
    }

getTextDimensions() [1/3]

bool mxvk::VK_Text::getTextDimensions	(	const std::string &	text,
		int &	width,
		int &	height )

Measure the pixel dimensions of a string with the current font.

Parameters

text	String to measure.
width	Output: pixel width.
height	Output: pixel height.

Returns

true if measurement succeeded.

Definition at line 604 of file mxvk_text.cpp.

                                                                                  {
        return getTextDimensions(text, width, height, font);
    }

getTextDimensions() [2/3]

bool mxvk::VK_Text::getTextDimensions	(	const std::string &	text,
		int &	width,
		int &	height,
		const Font &	textFont )

Definition at line 619 of file mxvk_text.cpp.

                                                                                                        {
        return getTextDimensions(text, width, height, textFont.get());
    }

getTextDimensions() [3/3]

bool mxvk::VK_Text::getTextDimensions	(	const std::string &	text,
		int &	width,
		int &	height,
		TTF_Font *	textFont )

Definition at line 608 of file mxvk_text.cpp.

                                                                                                      {
        if (text.empty() || !textFont) {
            width = 0;
            height = 0;
            return false;
        }
 
        // SDL3_ttf: TTF_GetStringSize replaces TTF_SizeText; length=0 for null-terminated
        return TTF_GetStringSize(textFont, text.c_str(), 0, &width, &height);
    }

operator=() [1/2]

VK_Text & mxvk::VK_Text::operator= ( const VK_Text & )

delete

operator=() [2/2]

VK_Text & mxvk::VK_Text::operator= ( VK_Text && )

delete

printTextG_Solid() [1/3]

void mxvk::VK_Text::printTextG_Solid	(	const std::string &	text,
		int	x,
		int	y,
		const SDL_Color &	col )

Queue a text string for solid (opaque) rendering.

Parameters

text	String to draw.
x	Destination X in pixels.
y	Destination Y in pixels.
col	Text colour.

Definition at line 298 of file mxvk_text.cpp.

                                                                                            {
        printTextG_SolidWithFont(text, x, y, col, font);
    }

printTextG_Solid() [2/3]

void mxvk::VK_Text::printTextG_Solid	(	const std::string &	text,
		int	x,
		int	y,
		const SDL_Color &	col,
		const Font &	textFont )

Definition at line 306 of file mxvk_text.cpp.

                                                                                                                  {
        printTextG_SolidWithFont(text, x, y, col, textFont.get());
    }

printTextG_Solid() [3/3]

void mxvk::VK_Text::printTextG_Solid	(	const std::string &	text,
		int	x,
		int	y,
		const SDL_Color &	col,
		TTF_Font *	textFont )

Definition at line 302 of file mxvk_text.cpp.

                                                                                                                {
        printTextG_SolidWithFont(text, x, y, col, textFont);
    }

renderText()

void mxvk::VK_Text::renderText	(	VkCommandBuffer	cmdBuffer,
		VkPipelineLayout	pipelineLayout,
		uint32_t	screenWidth,
		uint32_t	screenHeight )

Record all queued text quads into a command buffer.

Parameters

cmdBuffer	Active Vulkan command buffer.
pipelineLayout	Pipeline layout for push constants.
screenWidth	Viewport width.
screenHeight	Viewport height.

Definition at line 505 of file mxvk_text.cpp.

                                                                          {
 
        struct TextPushConstants {
            float screenWidth;
            float screenHeight;
            float alpha;
            float padding;
        } pc{static_cast<float>(screenWidth), static_cast<float>(screenHeight), 1.0f, 0.0f};
 
        for (auto &quad : textQuads) {
            pc.alpha = quad.alpha;
            vkCmdPushConstants(cmdBuffer, pipelineLayout, VK_SHADER_STAGE_VERTEX_BIT | VK_SHADER_STAGE_FRAGMENT_BIT, 0, sizeof(TextPushConstants), &pc);
            VkBuffer vertexBuffers[] = {quad.vertexBuffer};
            VkDeviceSize offsets[] = {0};
            vkCmdBindVertexBuffers(cmdBuffer, 0, 1, vertexBuffers, offsets);
            vkCmdBindIndexBuffer(cmdBuffer, quad.indexBuffer, 0, VK_INDEX_TYPE_UINT16);
            vkCmdBindDescriptorSets(cmdBuffer, VK_PIPELINE_BIND_POINT_GRAPHICS, pipelineLayout, 0, 1, &quad.descriptorSet, 0, nullptr);
 
            vkCmdDrawIndexed(cmdBuffer, quad.indexCount, 1, 0, 0, 0);
        }
    }

setDescriptorSetLayout()

void mxvk::VK_Text::setDescriptorSetLayout ( VkDescriptorSetLayout layout )

inline

Assign an external descriptor-set layout.

Definition at line 161 of file mxvk_text.hpp.

{ descriptorSetLayout = layout; }

setFont()

void mxvk::VK_Text::setFont	(	const std::string &	fontPath,
		int	fontSize )

Change the active font.

Parameters

fontPath	New font file path.
fontSize	New point size.

Definition at line 260 of file mxvk_text.cpp.

                                                                 {
        vkDeviceWaitIdle(device);
        clearQueue();
        clearCache();
        if (font) {
            TTF_CloseFont(font);
            font = nullptr;
        }
        if (fontSampler != VK_NULL_HANDLE) {
            vkDestroySampler(device, fontSampler, nullptr);
            fontSampler = VK_NULL_HANDLE;
        }
        initFont(fontPath, fontSize);
    }

Member Data Documentation

fontSampler

VkSampler mxvk::VK_Text::fontSampler = VK_NULL_HANDLE

Sampler used for all text textures.

Definition at line 184 of file mxvk_text.hpp.

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The documentation for this class was generated from the following files:

• mxvk/include/mxvk/mxvk_text.hpp
• mxvk/src/mxvk_text.cpp