Introduce Widget and Screen classes

src/Widget.cpp

@@ -0,0 +1,46 @@
+#include "Widget.h"
+#include "VertexArray.h"
+
+Widget::Widget(Texture *texture, float x, float y, float w, float h) :
+    x(x), y(y), w(w), h(h)
+{
+    widgetTextures.push_back(texture);
+    
+    const double ofst = 0.005;
+    
+    double widgetVerticesData[12] = {
+        x + w + ofst,       -1.0f + 2*y - ofst, 0.0f,   // Bottom right
+        -1.0f + 2*x - ofst, y + h + ofst,       0.0f,   // Top left
+        -1.0f + 2*x-ofst,   -1.0f + 2*y - ofst, 0.0f,   // Bottom left
+        x + w + ofst,       y + h + ofst,       0.0f    // Top right
+    };
+    
+    unsigned int widgetIndicesData[6] = {
+        0, 1, 2,
+        0, 3, 1
+    };
+    
+    float widgetTextureCoordinates[8] = {
+        1.0f, 0.0f,
+        0.0f, 1.0f,
+        0.0f, 0.0f,
+        1.0f, 1.0f
+    };
+    
+    widgetVertices = VertexArray::createVertices(widgetVerticesData, 12, widgetTextureCoordinates);
+    widgetIndices.assign(widgetIndicesData, widgetIndicesData + 6);
+    widgetMesh = new Mesh(widgetVertices, widgetIndices, widgetTextures);
+}
+
+Widget::~Widget()
+{
+    delete widgetMesh;
+}
+
+void Widget::draw(ShaderProgram *shaderProgram)
+{
+    shaderProgram->bind();
+    widgetMesh->draw(shaderProgram);
+    shaderProgram->unbind();
+}
+