add: RenderTarget

frame/src/render/RenderTarget.cpp

@@ -0,0 +1,49 @@
+#include "RenderTarget.hpp"
+
+namespace frame::render
+{
+
+    RenderTarget::RenderTarget(Size size)
+        : image(size)
+    {
+    }
+
+    void RenderTarget::DrawPixel(Vector const& position, Color color)
+    {
+        image.at(position.x, position.y) = color;
+    }
+
+    void RenderTarget::DrawLine(Vector const& start,
+                                Vector const& end,
+                                Color color)
+    {
+        auto const deltaX = std::abs(start.x - end.x);
+        auto const deltaY = std::abs(start.y - end.y);
+
+        auto const rX = start.x < end.x ? 1 : -1;
+        auto const rY = start.y < end.y ? 1 : -1;
+
+        auto pos = start;
+        auto E   = 2 * deltaY - deltaX;
+
+        DrawPixel(pos, color);
+
+        while(pos != end)
+        {
+            if(E <= 0)
+            {
+                pos.x += rX;
+
+                E += 2 * deltaY;
+            } else
+            {
+                pos.x += rX;
+                pos.y += rY;
+
+                E += 2 * deltaY - 2 * deltaX;
+            }
+            DrawPixel(pos, color);
+        }
+    }
+
+} // namespace frame::render