src dir for reasons

src/draw.h

@@ -0,0 +1,79 @@
+#ifndef DRAW_H
+#define DRAW_H
+
+#define DISPLAY_SCALE 0.8889
+
+#include "util.h"
+#include <stdint.h>
+
+typedef struct SDL_Window SDL_Window;
+
+// Call before window creation to setup backend-specific
+// hints and attributes.
+void DrawWindowHints(void);
+
+// Initialise the drawing subsystem.
+//
+// Params:
+//   window - The application's SDL window.
+//
+// Returns:
+//   0 on success, -1 on failure.
+int InitDraw(SDL_Window* window);
+
+// Quit the drawing subsystem.
+//
+// This is safe (but pointless) to call when the drawing
+// subsystem is uninitialised.
+void QuitDraw(void);
+
+// Get the actual size of the canvas in pixels.
+//
+// Returns:
+//   size struct with 'w' and 'h' set to the width &
+//   height of the canvas in actual pixels.
+size GetDrawSizeInPixels(void);
+
+// Call on resize for backends that need manual viewport resizing.
+void SetDrawViewport(size size);
+
+// Set the current draw colour.
+//
+// Params:
+//   c - Colour in the unsigned 32-bit int packed format of:
+//       0xFF000000 - red channel
+//       0x00FF0000 - blue channel
+//       0x0000FF00 - green channel
+//       0x000000FF - alpha channel
+void SetDrawColour(uint32_t c);
+
+// Clear the entire screen using the current draw colour.
+void DrawClear(void);
+
+// Draw a single pixel point at x, y w/ the draw colour.
+void DrawPoint(int x, int y);
+
+// Draw rectangle outline.
+void DrawRect(int x, int y, int w, int h);
+
+// Draw straight line between x1,y1 and x2,y2.
+void DrawLine(int x1, int y1, int x2, int y2);
+
+// Draw outline circle.
+void DrawCircle(int x, int y, int r);
+
+// Draw outline circle made of lines w/ a discrete number of steps.
+//
+// Can be used to draw regular convex polygons such as an octagon.
+void DrawCircleSteps(int x, int y, int r, int steps);
+
+// Draw an arc.
+void DrawArc(int x, int y, int r, int startAng, int endAng);
+
+// Draw an arc with a discrete number of steps.
+void DrawArcSteps(int x, int y, int r, int startAng, int endAng, int steps);
+
+// Present the current buffer to the screen.
+void DrawPresent(void);
+
+#endif//DRAW_H