1 files changed, 59 insertions, 0 deletions
diff --git a/kernel/framebuffer.cpp b/kernel/framebuffer.cpp
new file mode 100644
index 0000000..a115e0b
--- /dev/null
+++ b/kernel/framebuffer.cpp
@@ -0,0 +1,59 @@
+#include <mercury/kernel/framebuffer.hpp>
+
+namespace mercury::kernel::framebuffer {
+
+  uint32_t *vaddr;
+  int width;
+  int height;
+  int dword_pitch;
+
+  void init_framebuffer(
+    uint64_t vaddr, uint64_t width, uint64_t height, uint64_t pitch
+  ) {
+    //TODO: assumes 32-bpp rgb
+    framebuffer::vaddr = (uint32_t *)vaddr;
+    framebuffer::width = width;
+    framebuffer::height = height;
+    dword_pitch = pitch / 4;
+  }
+
+  color encode_color(uint8_t r, uint8_t g, uint8_t b) {
+    return ((uint32_t)r << 16) | ((uint32_t)g << 8) | (uint32_t)b;
+  }
+
+  void set_pixel(int x, int y, color c) {
+    vaddr[y * dword_pitch + x] = c;
+  }
+
+  void move_region(
+    int from_start_x, int from_start_y, int from_end_x,
+    int from_end_y, int to_start_x, int to_start_y
+  ) {
+
+    int region_width = from_end_x - from_start_x;
+    int region_height = from_end_y - from_start_y;
+
+    int from_start_offset = from_start_y * dword_pitch + from_start_x;
+    int to_start_offset = to_start_y * dword_pitch + to_start_x;
+
+    if (from_start_offset > to_start_offset)
+      for (int y = 0; y < region_height; ++y)
+        for (int x = 0; x < region_width; ++x)
+          vaddr[to_start_offset + y * dword_pitch + x] =
+            vaddr[from_start_offset + y * dword_pitch + x];
+
+    else if (from_start_offset < to_start_offset)
+      for (int y = region_height - 1; y >= 0; --y)
+        for (int x = region_width - 1; x >= 0; --x)
+          vaddr[to_start_offset + y * dword_pitch + x] =
+            vaddr[from_start_offset + y * dword_pitch + x];
+
+  }
+
+  void fill_region(int start_x, int start_y, int end_x, int end_y, color c) {
+    for (int y = start_y; y < end_y; ++y)
+      for (int x = start_x; x < end_x; ++x)
+        vaddr[y * dword_pitch + x] = c;
+  }
+
+}