DrawRectangle.hlsl

matrix orthoProjMatrix;
float4 elementSize;
float4 strokeWidth;

struct VertexShaderInput
{
	float3 position : POSITION0;
	float4 color : COLOR0;
	float2 texCoord : TEXCOORD0;
};

struct PixelShaderInput
{
	float4 position : POSITION0;
	float2 texCoord : TEXCOORD0;
	float4 color : TEXCOORD1;
};

void VertexMain(in VertexShaderInput vsInput, out PixelShaderInput output)
{
	output = (PixelShaderInput)0;

	output.position = mul(float4(vsInput.position, 1), orthoProjMatrix);
	output.texCoord = vsInput.texCoord;
	output.color = vsInput.color;
}

void PixelMain(in PixelShaderInput input, out float4 color : COLOR0)
{
	float texStepSizeX = strokeWidth.x / elementSize.x;
	float texStepSizeY = strokeWidth.x / elementSize.y;
	float2 tex = input.texCoord;

	if(tex.x <= texStepSizeX || tex.y <= texStepSizeY || (1.0f - tex.x) <= texStepSizeX || (1.0f - tex.y) <= texStepSizeY)
		color = input.color;
	else
		color = float4(0, 0, 0, 0);
}