// Samplers for textures
uniform sampler2D m_Texture;
uniform sampler2D m_OutlineDepthTexture;
uniform sampler2D m_DepthTexture;

// Input texture coordinates from the vertex shader
in vec2 texCoord;

// Resolution of the screen and outline settings
uniform vec2 m_Resolution;
uniform vec4 m_OutlineColor;
uniform float m_OutlineWidth;

// Output color of the fragment
out vec4 fragColor;

void main() {
    // Sample depth textures
    vec4 depth = texture(m_OutlineDepthTexture, texCoord);
    vec4 depth1 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(m_OutlineWidth, m_OutlineWidth)) / m_Resolution);
    vec4 depth2 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(m_OutlineWidth, -m_OutlineWidth)) / m_Resolution);
    vec4 depth3 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(-m_OutlineWidth, m_OutlineWidth)) / m_Resolution);
    vec4 depth4 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(-m_OutlineWidth, -m_OutlineWidth)) / m_Resolution);
    vec4 depth5 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(0.0, m_OutlineWidth)) / m_Resolution);
    vec4 depth6 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(0.0, -m_OutlineWidth)) / m_Resolution);
    vec4 depth7 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(m_OutlineWidth, 0.0)) / m_Resolution);
    vec4 depth8 = texture(m_OutlineDepthTexture, ((texCoord * m_Resolution) + vec2(-m_OutlineWidth, 0.0)) / m_Resolution);

    // Sample the main texture
    vec4 color = texture(m_Texture, texCoord);

    // Determine whether to apply the outline color
    if (depth == vec4(0.0) &&
       (depth1 != depth || depth2 != depth || depth3 != depth || depth4 != depth ||
        depth5 != depth || depth6 != depth || depth7 != depth || depth8 != depth)) {
        fragColor = m_OutlineColor; // Apply outline color
    } else {
        fragColor = color; // Use the original texture color
    }
}