fixing d3d11 depth buffers, adding depth buffer clear support

include/blah/graphics/framebuffer.h

@@ -14,6 +14,15 @@ namespace Blah
 	class FrameBuffer;
 	typedef std::shared_ptr<FrameBuffer> FrameBufferRef;
 
+	enum class ClearMask
+	{
+		None = 0,
+		Color = 1,
+		Depth = 2,
+		Stencil = 4,
+		All = (int)Color | (int)Depth | (int)Stencil
+	};
+
 	class FrameBuffer
 	{
 	protected:
@@ -56,7 +65,7 @@ namespace Blah
 		virtual int height() const = 0;
 
 		// Clears the FrameBuffer
-		virtual void clear(Color color) = 0;
+		virtual void clear(Color color = Color::black, float depth = 1.0f, uint8_t stencil = 0, ClearMask mask = ClearMask::All) = 0;
 	};
 
 }

include/blah/math/calc.h

@@ -61,6 +61,8 @@ namespace Blah
 
 		float cos(float x);
 
+		float tan(float x);
+
 		float atan2(float y, float x);
 
 		float pow(float x, float n);

include/blah/math/mat4x4.h

@@ -1,4 +1,5 @@
 #pragma once
+#include "vec3.h"
 
 namespace Blah
 {
@@ -36,8 +37,11 @@ namespace Blah
 
 		static Mat4x4 create_ortho(float width, float height, float z_near_plane, float z_far_plane);
 		static Mat4x4 create_ortho_offcenter(float left, float right, float bottom, float top, float z_near_plane, float z_far_plane);
+		static Mat4x4 create_perspective(float field_of_view, float ratio, float z_near_plane, float z_far_plane);
 		static Mat4x4 create_translation(float x, float y, float z);
 		static Mat4x4 create_scale(float x, float y, float z);
+		static Mat4x4 create_lookat(Vec3  position, Vec3 target, Vec3 up);
+
 
 		Mat4x4 operator* (const Mat4x4& rhs);
 	};

include/blah/math/vec3.h

@@ -1,4 +1,5 @@
 #pragma once
+#include "calc.h"
 
 namespace Blah
 {
@@ -19,5 +20,37 @@ namespace Blah
 			, y(y)
 			, z(z)
 		{}
+
+		inline Vec3 operator +(const Vec3 rhs) const
+		{
+			return Vec3(x + rhs.x, y + rhs.y, z + rhs.z);
+		}
+
+		inline Vec3 operator -(const Vec3 rhs) const
+		{
+			return Vec3(x + rhs.x, y + rhs.y, z + rhs.z);
+		}
+
+		inline Vec3 normal() const
+		{
+			float ls = x * x + y * y + z * z;
+			float length = (float)Calc::sqrt(ls);
+			return Vec3(x / length, y / length, z / length);
+		}
+
+		static inline float dot(Vec3 a, Vec3 b)
+		{
+			return a.x * b.x +
+				a.y * b.y +
+				a.z * b.z;
+		}
+
+		static inline Vec3 cross(Vec3 a, Vec3 b)
+		{
+			return Vec3(
+				a.y * b.z - a.z * b.y,
+				a.z * b.x - a.x * b.z,
+				a.x * b.y - a.y * b.x);
+		}
 	};
 }