Added rect draw api

Added some new maths types
Updated shaders to use new D_Rect structure
Added rect buffers to frames
Misc cleanup

code/vulkan/shaders/basic.frag

@@ -4,12 +4,12 @@
 
 layout(location = 0) in vec2 frag_uv;
 layout(location = 1) in vec4 frag_c;
-layout(location = 2) in flat uint idx;
+layout(location = 2) in flat uint texid;
 
 layout(location = 0) out vec4 framebuffer;
 
-layout(binding = 1) uniform sampler2D u_image[];
+layout(binding = 1) uniform sampler2D u_images[];
 
 void main() {
-	framebuffer = frag_c * texture(u_image[idx], frag_uv);
+	framebuffer = frag_c * texture(u_images[texid], frag_uv);
 }

code/vulkan/shaders/basic.vert

@@ -2,6 +2,28 @@
 
 #extension GL_EXT_scalar_block_layout : enable
 
+uint indices[6] = { 0, 1, 3, 0, 3, 2 };
+
+vec2 verticies[4] = vec2[](
+		vec2(-0.5, -0.5),
+		vec2( 0.5, -0.5),
+		vec2(-0.5,  0.5),
+		vec2( 0.5,  0.5)
+);
+
+struct G_Rect {
+	uint id;
+
+	uint   c[4];
+	float uv[4];
+
+	float angle;
+	float x, y;
+	float w, h;
+
+	float _pad0, _pad1;
+};
+
 struct Vertex {
 	vec4 p;
 	vec2 uv;
@@ -15,22 +37,28 @@ uniform Global {
 };
 
 layout(binding = 0, scalar)
-readonly buffer Vertices {
-	Vertex vtx[];
+readonly buffer Rect {
+	G_Rect rects[];
 };
 
 layout(location = 0) out vec2 frag_uv;
 layout(location = 1) out vec4 frag_c;
-layout(location = 2) out flat uint idx;
+layout(location = 2) out flat uint texid;
+
+vec4 unorm_colour(uint c) {
+	vec4 result = vec4((c >> 0) & 0xFF, (c >> 8) & 0xFF, (c >> 16) & 0xFF, (c >> 24) & 0xFF) / 255.0f;
+	return result;
+}
 
 void main() {
-	Vertex v = vtx[gl_VertexIndex];
+	G_Rect rect = rects[gl_InstanceIndex];
+	uint   idx  = indices[gl_VertexIndex];
 
-	gl_Position = proj * v.p;
+	vec2 p = (verticies[idx] * vec2(rect.w, rect.h)) + vec2(rect.x, rect.y);
 
-	frag_uv = v.uv;
-	frag_c  = vec4((v.c >> 24) & 0xFF, (v.c >> 16) & 0xFF, (v.c >> 8) & 0xFF, (v.c >> 0) & 0xFF) / 255.0f;
-	frag_c  = frag_c.abgr;
+	gl_Position = proj * vec4(p, 1.0f, 1.0f);
 
-	idx = v.pad;
+	frag_uv = vec2(rect.uv[(idx & 1) << 1], rect.uv[1 + (uint(idx / 2) << 1)]);
+	frag_c  = unorm_colour(rect.c[idx]);
+	texid   = rect.id;
 }