First pass UI Alignment

src/dawn/ui/UIComponent.cpp

@@ -4,29 +4,194 @@
 // https://opensource.org/licenses/MIT
 
 #include "UIComponent.hpp"
+#include "assert/assert.hpp"
 
 using namespace Dawn;
 
+UIComponent::UIComponent() {
+  alignUnit[0] = UIAlignmentUnit::SCALE;
+  alignUnit[1] = UIAlignmentUnit::SCALE;
+  alignUnit[2] = UIAlignmentUnit::SCALE;
+  alignUnit[3] = UIAlignmentUnit::SCALE;
+
+  eventAlignmentUpdated = [&](const glm::vec2 p, const glm::vec2 s) {
+  };
+}
+
+void UIComponent::updateAlignment(
+  const glm::vec2 pPos,
+  const glm::vec2 pSize,
+  const float_t canvasScale
+) {
+  auto valueAxis = [&](
+    const enum UIAlignmentUnit unit,
+    const float_t alignment,
+    const float_t parentSize,
+    const float_t ratioSize
+  ) {
+    switch(unit) {
+      case UIAlignmentUnit::PIXEL:
+        return alignment;
+
+      case UIAlignmentUnit::SCALE:
+        return canvasScale * alignment;
+
+      case UIAlignmentUnit::PERCENT:
+        return parentSize * (alignment / 100.0f);
+
+      case UIAlignmentUnit::RATIO:
+        return (alignment / 100.0f) * ratioSize;
+      
+      default:
+        assertUnreachable("Invalid UIAlignmentType");
+        return 0.0f;
+    }
+  };
+
+  auto alignAxis = [&](
+    const enum UIAlignmentType type,
+    const enum UIAlignmentUnit unit0,
+    const enum UIAlignmentUnit unit1,
+    const float_t alignment0,
+    const float_t alignment1,
+    const float_t parentSize,
+    const float_t ratioSize,
+    float_t &selfPosition,
+    float_t &selfSize
+  ) {
+    switch(type) {
+      case UIAlignmentType::START:
+        selfPosition = valueAxis(
+          unit0,
+          alignment0,
+          parentSize,
+          ratioSize
+        );
+        selfSize = valueAxis(
+          unit1,
+          alignment1,
+          parentSize,
+          ratioSize
+        );
+        break;
+
+      case UIAlignmentType::MIDDLE:
+        selfSize = valueAxis(
+          unit1,
+          alignment1,
+          parentSize,
+          ratioSize
+        );
+        selfPosition = (parentSize / 2.0f) - (selfSize / 2.0f) + valueAxis(
+          unit0,
+          alignment0,
+          parentSize,
+          ratioSize
+        );
+        break;
+
+      case UIAlignmentType::END:
+        selfSize = valueAxis(
+          unit0,
+          alignment0,
+          parentSize,
+          ratioSize
+        );
+        selfPosition = parentSize - selfSize - valueAxis(
+          unit1,
+          alignment1,
+          parentSize,
+          ratioSize
+        );
+        break;
+
+      case UIAlignmentType::STRETCH:
+        selfPosition = valueAxis(
+          unit0,
+          alignment0,
+          parentSize,
+          ratioSize
+        );
+        selfSize = parentSize - (selfPosition + valueAxis(
+          unit1,
+          alignment1,
+          parentSize,
+          ratioSize
+        ));
+        break;
+
+      default:
+        assertUnreachable("Invalid UIAlignmentType");
+    }
+  };
+
+  bool_t heightFirst = (
+    alignUnit[0] == UIAlignmentUnit::RATIO ||
+    alignUnit[2] == UIAlignmentUnit::RATIO
+  );
+
+  if(heightFirst) {
+    // Align height first, this will define size.y which we can use as the ratio
+    // for the width/X axis alignment.
+    alignAxis(
+      alignY,
+      alignUnit[1],
+      alignUnit[3],
+      align[1],
+      align[3],
+      pSize.y,
+      0,
+      position.y,
+      size.y
+    );
+    alignAxis(
+      alignX,
+      alignUnit[0],
+      alignUnit[2],
+      align[0],
+      align[2],
+      pSize.x,
+      size.y,
+      position.x,
+      size.x
+    );
+  } else {
+    alignAxis(
+      alignX,
+      alignUnit[0],
+      alignUnit[2],
+      align[0],
+      align[2],
+      pSize.x,
+      0,
+      position.x,
+      size.x
+    );
+    alignAxis(
+      alignY,
+      alignUnit[1],
+      alignUnit[3],
+      align[1],
+      align[3],
+      pSize.y,
+      size.x,
+      position.y,
+      size.y
+    );
+  }
+
+  this->eventAlignmentUpdated(position, size);
+}
+
 std::vector<std::shared_ptr<UIComponent>> UIComponent::getChildren() {
   return {};
 }
 
-void UIComponent::getQuads(
-  const struct UIAlign alignment,
-  UICanvas &ctx
-) {
-  auto selfAlignment = getSelfAlignment(alignment);
-  this->getSelfQuads(selfAlignment, ctx);
+void UIComponent::getQuads(UICanvas &ctx) {
+  this->getSelfQuads(ctx);
 
   auto children = getChildren();
   for(auto &c : children) {
-    c->getQuads(selfAlignment, ctx);
+    c->getQuads(ctx);
   }
-}
-
-struct UIAlign UIComponent::getSelfAlignment(const struct UIAlign alignment) {
-  return (struct UIAlign){
-    alignment.position + position,
-    alignment.size
-  };
 }

src/dawn/ui/UIComponent.hpp

@@ -8,13 +8,25 @@
 #include "component/ui/UICanvas.hpp"
 
 namespace Dawn {
-  struct UIAlign {
-    glm::vec2 position;
-    glm::vec2 size;
+  enum class UIAlignmentType {
+    START,
+    MIDDLE,
+    END,
+    STRETCH
+  };
+
+  enum class UIAlignmentUnit {
+    PIXEL,
+    SCALE,
+    PERCENT,
+    RATIO
   };
 
   class UIComponent {
     protected:
+      glm::vec2 position;
+      glm::vec2 size;
+
       /**
        * Virtual method overridden by the UIComponent to get the quads for the
        * component.
@@ -22,21 +34,34 @@ namespace Dawn {
        * @param alignment The alignment of this component.
        * @param ctx The canvas to add the quads to.
        */
-      virtual void getSelfQuads(
-        const struct UIAlign alignment,
-        UICanvas &ctx
-      ) = 0;
+      virtual void getSelfQuads(UICanvas &ctx) = 0;
 
       /**
-       * Allows a component to modify its self alignment.
+       * Updates the alignment of this component based on the parent.
        * 
-       * @param alignment Aliugnment to modify.
-       * @return New alignment for this component.
+       * @param parentPosition The position of the parent.
+       * @param parentSize The size of the parent.
        */
-      virtual struct UIAlign getSelfAlignment(const struct UIAlign alignment);
+      void updateAlignment(
+        const glm::vec2 parentPosition,
+        const glm::vec2 parentSize,
+        const float_t canvasScale
+      );
 
     public:
-      glm::vec2 position;
+      glm::vec4 align = glm::vec4(0, 0, 32, 32);
+      enum UIAlignmentType alignX = UIAlignmentType::START;
+      enum UIAlignmentType alignY = UIAlignmentType::START;
+      enum UIAlignmentUnit alignUnit[4];
+
+      std::function<
+        void(const glm::vec2, const glm::vec2)
+      > eventAlignmentUpdated;
+
+      /**
+       * Instantiates a new UIComponent.
+       */
+      UIComponent();
 
       /**
        * Virtual method overridden by the UIComponent to get the children of
@@ -47,12 +72,10 @@ namespace Dawn {
       /**
        * Method called by the UICanvas to get the quads for this component.
        * 
-       * @param alignment The alignment of this component.
        * @param ctx The canvas to add the quads to.
        */
-      void getQuads(
-        const struct UIAlign alignment,
-        UICanvas &ctx
-      );
+      void getQuads(UICanvas &ctx);
+
+      friend class UICanvas;
   };
 }

src/dawn/ui/UILabel.cpp

@@ -7,24 +7,67 @@
 
 using namespace Dawn;
 
-void UILabel::getSelfQuads(
-  const struct UIAlign alignment,
-  UICanvas &ctx
-) {
+void UILabel::getSelfQuads(UICanvas &ctx) {
   std::vector<struct UIShaderQuad> quads;
   if(this->texture == nullptr || this->text.empty()) return;
 
   glm::vec4 quad;
-  glm::vec2 pos = alignment.position;
+  glm::vec2 pos = glm::vec2(0, this->texture->fontSize);
+  bool_t lastCharWasSpace = false;
 
-  for(wchar_t c : text) {
+  for(size_t i = 0; i < text.size(); i++) {
+    wchar_t c = text[i];
     auto info = texture->getCharacterData(c);
+
+    // Newline(s)
+    if(c == L'\n') {
+      pos.x = 0;
+      pos.y += this->texture->fontSize;
+      continue;
+    }
+
+    // Spaces
+    if(c == L' ') {
+      pos.x += info.advance.x;
+      lastCharWasSpace = true;
+      continue;
+    }
+
+    // Word Wrap
+    if(wordWrap) {
+      if(lastCharWasSpace) {
+        // Scan ahead to next space
+        float_t wordWidth = pos.x;// Start at current position and scan ahead.
+        for(size_t j = i; j < text.size(); j++) {
+          wchar_t c2 = text[j];
+          if(c2 == L' ' || c2 == L'\n') {
+            break;// If we hit another space, we are OK.
+          }
+
+          // Will this character fit on the row? If not the whole word will wrap.
+          auto info2 = texture->getCharacterData(c);
+          wordWidth += info.advance.x;
+          if(wordWidth > size.x) {
+            pos.x = 0;
+            pos.y += this->texture->fontSize;
+            break;
+          }
+        }
+
+        lastCharWasSpace = false;
+      }
+    } else if(pos.x + info.size.x > position.x + size.x) {
+      // Not word wrap, but instead just overflow characters.
+      pos.x = 0;
+      pos.y += this->texture->fontSize;
+    }
+
     ctx.addQuad(
       {
-        pos.x + info.offset.x,
-        pos.y + info.offset.y,
-        pos.x + info.size.x + info.offset.x,
-        pos.y + info.size.y + info.offset.y
+        position.x + pos.x + info.offset.x,
+        position.y + pos.y + info.offset.y,
+        position.x + pos.x + info.size.x + info.offset.x,
+        position.y + pos.y + info.size.y + info.offset.y
       },
       {
         info.quad.x,

src/dawn/ui/UILabel.hpp

@@ -14,12 +14,11 @@ namespace Dawn {
       std::wstring text = L"Hello World";
 
     protected:
-      void getSelfQuads(
-        const struct UIAlign alignment,
-        UICanvas &ctx
-      ) override;
+      void getSelfQuads(UICanvas &ctx) override;
 
     public:
+      bool_t wordWrap = true;
+
       /**
        * Returns the font used for this label.
        * 

src/dawn/ui/UIRectangle.cpp

@@ -7,13 +7,10 @@
 
 using namespace Dawn;
 
-void UIRectangle::getSelfQuads(
-  const struct UIAlign alignment,
-  UICanvas &ctx
-) {
+void UIRectangle::getSelfQuads(UICanvas &ctx) {
   std::vector<struct UIShaderQuad> quads;
   ctx.addQuad(
-    glm::vec4(alignment.position, alignment.position + size),
+    glm::vec4(position, position + size),
     uv,
     color,
     UIShaderQuadStyle::TEXTURED,

src/dawn/ui/UIRectangle.hpp

@@ -9,15 +9,11 @@
 namespace Dawn {
   class UIRectangle final : public UIComponent {
     protected:
-      void getSelfQuads(
-        const struct UIAlign alignment,
-        UICanvas &ctx
-      ) override;
+      void getSelfQuads(UICanvas &ctx) override;
 
     public:
       struct Color color = COLOR_WHITE;
       std::shared_ptr<Texture> texture = nullptr;
-      glm::vec2 size = glm::vec2(32, 32);
       glm::vec4 uv = glm::vec4(0,0,1,1);
   };
 }