From a6a419fdff1c3d1b1b2de32dfd86458eb715f966 Mon Sep 17 00:00:00 2001
From: EmaMaker <emamaker0@gmail.com>
Date: Sun, 17 Sep 2023 15:50:54 +0200
Subject: [PATCH] hud: crosshair with fragment shader

---
 shaders/shader-quad.fs | 18 ++++++++++++++++++
 src/renderer.cpp       |  3 +++
 2 files changed, 21 insertions(+)

diff --git a/shaders/shader-quad.fs b/shaders/shader-quad.fs
index c4dc9a6..de35cc8 100644
--- a/shaders/shader-quad.fs
+++ b/shaders/shader-quad.fs
@@ -4,7 +4,25 @@ in vec2 TexCoord;
 out vec4 FragColor;
 
 uniform sampler2D renderTex;
+uniform int screenWidth;
+uniform int screenHeight;
+uniform int crosshairType;
 
 void main(){
+    float crosshair_alpha = 0.8;
+
+    float dist = length(gl_FragCoord.xy-vec2(screenWidth/2, screenHeight/2));
+
     FragColor = texture(renderTex, TexCoord);
+    /*float crosshair_color = (FragColor.x + FragColor.y + FragColor.z) / 3;
+    /*if(crosshair_color <= 0.5) crosshair_color = 1.0;
+    /*else crosshair_color = 0.0;*/
+    float crosshair_color = 1.0;
+
+    if(dist <= 7){
+	if( (crosshairType == 0 && dist >= 5) ||
+		(crosshairType == 1 && ( int(gl_FragCoord.x) == int(screenWidth / 2) ||
+		 int(gl_FragCoord.y) == int(screenHeight / 2)) )
+	    ) FragColor = vec4(vec3(crosshair_color), crosshair_alpha);
+	}
 }
diff --git a/src/renderer.cpp b/src/renderer.cpp
index eeaae93..ddd8a28 100644
--- a/src/renderer.cpp
+++ b/src/renderer.cpp
@@ -217,6 +217,9 @@ namespace renderer{
 	glDisable(GL_DEPTH_TEST);
 	glBindTexture(GL_TEXTURE_2D, renderTex);
 	quadShader->use();
+	quadShader->setInt("screenWidth", screenWidth);
+	quadShader->setInt("screenHeight", screenHeight);
+	quadShader->setInt("crosshairType", 1);
 	glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
 	glBindVertexArray(0);
     }