Improve TextFieldElement

src/kekengine/cpp/render/fonts.cpp

@@ -2,9 +2,11 @@
 
 #include <GL/glew.h>
 #include <GLFW/glfw3.h>
+#include <algorithm>
 #include <glm/gtc/type_ptr.hpp>
 #include <iostream>
 #include <stb_image_write.h>
+#include <string>
 
 #include "constants.h"
 #include "engine.h"
@@ -16,7 +18,7 @@ namespace kek {
 
 Shader *fontShader = nullptr;
 
-TextObject::TextObject(Font *font, std::string text) {
+TextObject::TextObject(std::shared_ptr<Font> font, std::string text) {
 	assert(text.length() > 0);
 
 	this->font = font;
@@ -52,7 +54,7 @@ TextObject &TextObject::operator=(TextObject &&other) {
 	return *this;
 }
 
-Font *TextObject::getFont() {
+std::shared_ptr<Font> TextObject::getFont() {
 	return font;
 }
 
@@ -65,26 +67,17 @@ std::string TextObject::getText() {
 	return text;
 }
 
+TextMetrics TextObject::getMetrics(unsigned int offset, unsigned int length, int sizePixels) {
+	TextMetrics metrics = measureChars(Unicode::convertStdToU32(text), offset, length, nullptr);
+	float sizeRatio = (float) sizePixels / KEK_FONT_RESOLUTION;
+	return TextMetrics((int) (sizeRatio * metrics.offsetX), (int) (sizeRatio * metrics.offsetY), (int) (sizeRatio * metrics.width), (int) (sizeRatio * metrics.height));
+}
+
 TextMetrics TextObject::getMetrics(int sizePixels) {
 	float sizeRatio = (float) sizePixels / KEK_FONT_RESOLUTION;
-	return TextMetrics((int) (sizeRatio * offsetX), (int) (sizeRatio * offsetY), (int) (sizeRatio * width), (int) (sizeRatio * height));
+	return TextMetrics((int) (sizeRatio * unscaledMetrics.offsetX), (int) (sizeRatio * unscaledMetrics.offsetY), (int) (sizeRatio * unscaledMetrics.width), (int) (sizeRatio * unscaledMetrics.height));
 }
 
-struct RenderChar {
-	float data[24];
-
-	RenderChar(float xPos, float yPos, float w, float h, float texL, float texR, float texU, float texD) {
-		float coords[] = {
-			xPos, yPos, texL, texU,
-			xPos, yPos + h, texL, texD,
-			xPos + w, yPos, texR, texU,
-			xPos + w, yPos, texR, texU,
-			xPos, yPos + h, texL, texD,
-			xPos + w, yPos + h, texR, texD};
-		for(int i = 0; i < 24; i++) data[i] = coords[i];
-	}
-};
-
 void TextObject::allocateBuffer(TextBlock *block, int numChars) {
 	unsigned int targetSize = (numChars + KEK_TEXT_BLOCK_SIZE - 1) / KEK_TEXT_BLOCK_SIZE * KEK_TEXT_BLOCK_SIZE; // ceil(numChars / KEK_TEXT_BLOCK_SIZE) * KEK_TEXT_BLOCK_SIZE
 	block->bufferSize = targetSize;
@@ -106,9 +99,11 @@ void TextObject::allocateBuffer(TextBlock *block, int numChars) {
 	glBindVertexArray(0);
 }
 
-void TextObject::loadChars() {
+TextMetrics TextObject::measureChars(std::u32string str, unsigned int offset, unsigned int length, std::map<unsigned int, std::vector<RenderChar>> *chars) {
-	std::map<unsigned int, std::vector<RenderChar>> chars;
+	if(offset != 0 || length != str.length()) {
-	std::u32string str = Unicode::convertStdToU32(text);
+		length = std::min(length, (unsigned int) (str.length() - offset));
+		str = str.substr(offset, length);
+	}
 
 	float x = 0, y = 0;
 	int lineHeight = font->getDefaultMetrics().lineHeight;
@@ -132,6 +127,9 @@ void TextObject::loadChars() {
 		float h = ch.size.y;
 		if(h > maxH) maxH = h;
 
+		if(chars != nullptr) {
+			auto &_chars = *chars;
+
 			float texL = (ch.textureX) / (float) KEK_FONT_BITMAP_WIDTH;
 			float texR = (ch.textureX + ch.size.x) / (float) KEK_FONT_BITMAP_WIDTH;
 			float texU = (ch.textureY) / (float) KEK_FONT_BITMAP_HEIGHT;
@@ -139,22 +137,28 @@ void TextObject::loadChars() {
 
 			RenderChar rCh = RenderChar(xPos, yPos, w, h, texL, texR, texU, texD);
 
-		auto charsForBlock = chars.find(charBlock);
+			auto charsForBlock = _chars.find(charBlock);
-		if(charsForBlock != chars.end()) {
+			if(charsForBlock != _chars.end()) {
 				charsForBlock->second.push_back(rCh);
 			} else {
 				std::vector<RenderChar> chs;
 				chs.push_back(rCh);
-			chars[charBlock] = chs;
+				_chars[charBlock] = chs;
+			}
 		}
 
 		x += (ch.advance >> 6); // == ch.advance / 64
 	}
 
-	this->offsetX = offX;
+	return TextMetrics(offX, offY, x, maxH);
-	this->offsetY = offY;
+}
-	this->width = x;
+
-	this->height = maxH;
+void TextObject::loadChars() {
+	std::map<unsigned int, std::vector<RenderChar>> chars;
+	std::u32string str = Unicode::convertStdToU32(text);
+
+	TextMetrics metrics = measureChars(str, 0, str.length(), &chars);
+	this->unscaledMetrics = metrics;
 
 	auto it = chars.begin();
 	while(it != chars.end()) {
@@ -284,10 +288,6 @@ CharacterBlock Font::generateCharacterBlock(unsigned int block) {
 	return chBlock;
 }
 
-TextObject *Font::createText(std::string text) {
-	return new TextObject(this, text);
-}
-
 FontMetrics Font::getDefaultMetrics() {
 	return FontMetrics(lineHeight >> 6, ascender >> 6, descender >> 6);
 }
@@ -340,4 +340,18 @@ void Font::drawTextCentered(TextObject *textObject, glm::mat4 projection, int x,
 	Font::drawText(textObject, projection, x - metrics.offsetX + metrics.width / 2, y + metrics.offsetY - metrics.height / 2, sizePixels, color);
 }
 
+std::shared_ptr<Font> Font::load(std::string fontPath) {
+	std::shared_ptr<Font> ret = nullptr;
+
+	auto iter = kekData.loadedFonts.find(fontPath);
+	if(iter != kekData.loadedFonts.end()) ret = iter->second.lock();
+
+	if(!ret) {
+		ret = std::make_shared<Font>(fontPath);
+		kekData.loadedFonts.emplace(fontPath, ret);
+	}
+
+	return ret;
+}
+
 }

src/kekengine/cpp/render/texture.cpp

@@ -56,7 +56,7 @@ void Texture::use(GLenum texture) {
 }
 
 std::shared_ptr<Texture> Texture::load(std::string texturePath) {
-	std::shared_ptr<Texture> ret;
+	std::shared_ptr<Texture> ret = nullptr;
 
 	auto iter = kekData.loadedTextures.find(texturePath);
 	if(iter != kekData.loadedTextures.end()) ret = iter->second.lock();

src/kekengine/cpp/ui/ui.cpp

@@ -244,12 +244,12 @@ UIElement *UIElement::dragEnterAll(UIPoint pos, UIPoint screenPos) {
 
 void UI::init() {
 	kekData.ui = new UIData();
-	kekData.ui->defaultFont = new Font(KEK_DEFAULT_FONT);
+	kekData.ui->defaultFont = Font::load(KEK_DEFAULT_FONT);
 	kekData.ui->rectangleShader = new Shader("shader/rectangle/vertex.glsl", "shader/rectangle/fragment.glsl");
 }
 
 void UI::destroy() {
-	delete kekData.ui->defaultFont;
+	kekData.ui->defaultFont = nullptr;
 	delete kekData.ui->rectangleShader;
 	delete kekData.ui;
 }

src/kekengine/cpp/ui/uielements.cpp

@@ -2,8 +2,10 @@
 
 #include <GLFW/glfw3.h>
 #include <glm/gtc/type_ptr.hpp>
+#include <string>
 
 #include "constants.h"
+#include "fonts.h"
 #include "input.h"
 #include "internal.h"
 #include "internal/ui.h"
@@ -13,7 +15,7 @@
 
 namespace kek {
 
-TextElement::TextElement(UIValue x, UIValue y, Font *font)
+TextElement::TextElement(UIValue x, UIValue y, std::shared_ptr<Font> font)
 	: UIElement(x, y) {
 	this->text = new TextObject(font, "Text");
 	this->sizePixels = KEK_DEFAULT_FONT_SIZE_PIXELS;
@@ -195,7 +197,7 @@ void ButtonElement::draw(UIPoint screenPos, glm::mat4 projection) {
 	RectangleElement::draw(screenPos, projection);
 }
 
-TextFieldElement::TextFieldElement(UIValue x, UIValue y, UIValue w, Font *font)
+TextFieldElement::TextFieldElement(UIValue x, UIValue y, UIValue w, std::shared_ptr<Font> font)
 	: RectangleElement(x, y, w, uiPx(0)) {
 	this->enableClipping = true;
 	this->focusable = true;
@@ -233,6 +235,14 @@ TextFieldElement::~TextFieldElement() {
 	delete cursor;
 }
 
+void TextFieldElement::updateText(std::u32string newText) {
+	this->text = Unicode::convertU32ToStd(newText);
+	this->textElement->setText(this->text);
+
+	TextMetrics m = textElement->text->getMetrics(0, newText.length() - cursorPos, textElement->sizePixels);
+	this->cursor->x = uiPx(m.width);
+}
+
 UIElementType TextFieldElement::getType() {
 	return UIElementType::TEXT_FIELD;
 }
@@ -247,23 +257,43 @@ void TextFieldElement::focusEnter() {
 
 			std::u32string str = Unicode::convertStdToU32(_this->text);
 			if(event.codepoint == KEK_INPUT_DELETE) {
-				if(str.length() == 0) return;
+				if(_this->cursorPos == str.length()) return;
-				str = str.substr(0, str.length() - 1);
+				str = str.erase(str.length() - _this->cursorPos - 1, 1);
 			} else {
-				str.push_back(event.codepoint);
+				str.insert(str.length() - _this->cursorPos, 1, event.codepoint);
 			}
 
-			_this->text = Unicode::convertU32ToStd(str);
-			_this->textElement->setText(_this->text);
-
 			_this->lastCharTyped = glfwGetTime();
-			_this->cursor->x = uiPx(_this->textElement->getBounds().w);
+			_this->updateText(str);
 		},
 			this),
 		KeyCallback([](KeyEvent event, void *data) {
 			TextFieldElement *_this = (TextFieldElement *) data;
-			if(event.key == GLFW_KEY_ENTER && event.action == GLFW_PRESS) {
+
+			if(event.action == GLFW_PRESS || event.action == GLFW_REPEAT) {
+				switch(event.key) {
+					case GLFW_KEY_ENTER:
 						Input::uncaptureKeyboardInput(_this->capture);
+						break;
+					case GLFW_KEY_LEFT: {
+						std::u32string str = Unicode::convertStdToU32(_this->text);
+						if(_this->cursorPos < str.length()) {
+							_this->cursorPos++;
+							_this->updateText(str);
+							_this->lastCharTyped = glfwGetTime();
+						}
+						break;
+					}
+					case GLFW_KEY_RIGHT: {
+						std::u32string str = Unicode::convertStdToU32(_this->text);
+						if(_this->cursorPos > 0) {
+							_this->cursorPos--;
+							_this->updateText(str);
+							_this->lastCharTyped = glfwGetTime();
+						}
+						break;
+					}
+				}
 			}
 		},
 			this),

src/kekengine/include/fonts.h

@@ -1,6 +1,7 @@
 #pragma once
 
 #include <ft2build.h>
+#include <memory>
 #include FT_FREETYPE_H
 #include <glm/glm.hpp>
 
@@ -31,12 +32,17 @@ struct TextMetrics {
 	int width;
 	int height;
 
-	TextMetrics(int offsetX, int offsetY, unsigned int width, unsigned int height) {
+	TextMetrics()
-		this->offsetX = offsetX;
+		: offsetX(0),
-		this->offsetY = offsetY;
+		  offsetY(0),
-		this->width = width;
+		  width(0),
-		this->height = height;
+		  height(0) {}
-	}
+
+	TextMetrics(int offsetX, int offsetY, unsigned int width, unsigned int height)
+		: offsetX(offsetX),
+		  offsetY(offsetY),
+		  width(width),
+		  height(height) {}
 };
 
 struct FontMetrics {
@@ -62,21 +68,33 @@ struct TextBlock {
 	unsigned int vbo;
 };
 
+struct RenderChar {
+	float data[24];
+
+	RenderChar(float xPos, float yPos, float w, float h, float texL, float texR, float texU, float texD) {
+		float coords[] = {
+			xPos, yPos, texL, texU,
+			xPos, yPos + h, texL, texD,
+			xPos + w, yPos, texR, texU,
+			xPos + w, yPos, texR, texU,
+			xPos, yPos + h, texL, texD,
+			xPos + w, yPos + h, texR, texD};
+		for(int i = 0; i < 24; i++) data[i] = coords[i];
+	}
+};
+
 class TextObject {
 
   private:
-	Font *font;
+	std::shared_ptr<Font> font;
 	std::string text;
 
-	int offsetX;
+	TextMetrics unscaledMetrics;
-	int offsetY;
-	int width;
-	int height;
 
   public:
 	std::map<unsigned int, TextBlock> blocks;
 
-	TextObject(Font *font, std::string text);
+	TextObject(std::shared_ptr<Font> font, std::string text);
 
 	~TextObject();
 
@@ -88,12 +106,14 @@ class TextObject {
 
 	TextObject &operator=(TextObject &&other);
 
-	Font *getFont();
+	std::shared_ptr<Font> getFont();
 
 	void setText(std::string text);
 
 	std::string getText();
 
+	TextMetrics getMetrics(unsigned int offset, unsigned int length, int sizePixels);
+
 	TextMetrics getMetrics(int sizePixels);
 
   private:
@@ -101,6 +121,8 @@ class TextObject {
 
 	void allocateBuffer(TextBlock *block, int numChars);
 
+	TextMetrics measureChars(std::u32string str, unsigned int offset, unsigned int length, std::map<unsigned int, std::vector<RenderChar>> *chars);
+
 	void loadChars();
 };
 
@@ -123,8 +145,6 @@ class Font {
 
 	CharacterBlock getCharacterBlock(unsigned int block);
 
-	TextObject *createText(std::string text);
-
 	FontMetrics getDefaultMetrics();
 
 	FontMetrics getMetrics(int sizePixels);
@@ -149,6 +169,9 @@ class Font {
 	// Draws text centered around (x,y)
 	void drawTextCentered(TextObject *textObject, glm::mat4 projection, int x, int y, int sizePixels, Color color);
 
+	// Loads a font from resources
+	static std::shared_ptr<Font> load(std::string path);
+
   private:
 	CharacterBlock generateCharacterBlock(unsigned int block);
 };

src/kekengine/include/internal.h

@@ -33,6 +33,7 @@ struct KekData {
 	float lastFrameTime;
 
 	std::map<std::string, std::weak_ptr<Texture>> loadedTextures;
+	std::map<std::string, std::weak_ptr<Font>> loadedFonts;
 
 	FT_Library freetype;
 

src/kekengine/include/internal/ui.h

@@ -7,7 +7,7 @@ namespace kek {
 struct UIData {
 	std::vector<UIElement *> elements;
 	UIElement *focusedElement;
-	Font *defaultFont;
+	std::shared_ptr<Font> defaultFont;
 	Shader *rectangleShader;
 };
 

src/kekengine/include/uielements.h

@@ -30,16 +30,15 @@ enum class TextBounds {
 
 class TextElement: public UIElement {
 
-  protected:
+  public:
 	TextObject *text;
 
-  public:
 	int sizePixels;
 	Color color;
 	TextMode textMode;
 	TextBounds textBounds;
 
-	TextElement(UIValue x, UIValue y, Font *font);
+	TextElement(UIValue x, UIValue y, std::shared_ptr<Font> font);
 
 	TextElement(UIValue x, UIValue y);
 
@@ -109,9 +108,12 @@ class TextFieldElement: public RectangleElement {
 
 	KeyboardCapture capture;
 	float lastCharTyped = 0;
+	unsigned int cursorPos = 0; // Cursor offset from the back of the string
+
+	void updateText(std::u32string newText);
 
   public:
-	TextFieldElement(UIValue x, UIValue y, UIValue w, Font *font);
+	TextFieldElement(UIValue x, UIValue y, UIValue w, std::shared_ptr<Font> font);
 
 	TextFieldElement(UIValue x, UIValue y, UIValue w);