From cb8d30543ec5197c0bea496eda8550b76c135642 Mon Sep 17 00:00:00 2001
From: Dave Smith <davesmith.00000@gmail.com>
Date: Tue, 2 Jan 2024 12:28:14 +0000
Subject: [PATCH] Fixed #103: Missing != operator

---
 .../ultraviolet/macros/CreateShaderAST.scala  | 36 +++++++++++++++++--
 .../acceptance/GLSLIfStatementTests.scala     | 26 ++++++++++++++
 2 files changed, 60 insertions(+), 2 deletions(-)

diff --git a/ultraviolet/shared/src/main/scala/ultraviolet/macros/CreateShaderAST.scala b/ultraviolet/shared/src/main/scala/ultraviolet/macros/CreateShaderAST.scala
index 7d18638..526481a 100644
--- a/ultraviolet/shared/src/main/scala/ultraviolet/macros/CreateShaderAST.scala
+++ b/ultraviolet/shared/src/main/scala/ultraviolet/macros/CreateShaderAST.scala
@@ -1184,7 +1184,23 @@ class CreateShaderAST[Q <: Quotes](using val qq: Q) extends ShaderMacroUtils:
 
       case Apply(Select(term, op), xs) =>
         op match
-          case "+" | "-" | "*" | "/" | "<" | ">" | "==" | "<=" | ">=" | "&&" | "||" =>
+          case "<" | "<=" | ">" | ">=" | "==" | "!=" =>
+            // Vector Relational Functions, according to the spec TL;DR: the left and right side types must be the same.
+            // However, we don't have a nice way to do that check yet.
+            val lhs = walkTerm(term, envVarName)
+            val rhs = xs.headOption.map(tt => walkTerm(tt, envVarName)).getOrElse(ShaderAST.Empty())
+            val rt  = findReturnType(lhs)
+            ShaderAST.Infix(op, lhs, rhs, rt)
+
+          case "+" | "-" | "*" | "/" =>
+            // Math operators.
+            val lhs = walkTerm(term, envVarName)
+            val rhs = xs.headOption.map(tt => walkTerm(tt, envVarName)).getOrElse(ShaderAST.Empty())
+            val rt  = findReturnType(lhs)
+            ShaderAST.Infix(op, lhs, rhs, rt)
+
+          case "&&" | "||" =>
+            // Logical operators.
             val lhs = walkTerm(term, envVarName)
             val rhs = xs.headOption.map(tt => walkTerm(tt, envVarName)).getOrElse(ShaderAST.Empty())
             val rt  = findReturnType(lhs)
@@ -1210,7 +1226,23 @@ class CreateShaderAST[Q <: Quotes](using val qq: Q) extends ShaderMacroUtils:
 
       case Apply(Apply(Ident(op), List(l)), List(r)) =>
         op match
-          case "+" | "-" | "*" | "/" | "<" | ">" | "==" | "<=" | ">=" | "&&" | "||" =>
+          case "<" | "<=" | ">" | ">=" | "==" | "!=" =>
+            // Vector Relational Functions, according to the spec. TL;DR: the left and right side types must be the same.
+            // However, we don't have a nice way to do that check yet.
+            val lhs = walkTerm(l, envVarName)
+            val rhs = walkTerm(r, envVarName)
+            val rt  = findReturnType(lhs)
+            ShaderAST.Infix(op, lhs, rhs, rt)
+
+          case "+" | "-" | "*" | "/" =>
+            // Math operators.
+            val lhs = walkTerm(l, envVarName)
+            val rhs = walkTerm(r, envVarName)
+            val rt  = findReturnType(lhs)
+            ShaderAST.Infix(op, lhs, rhs, rt)
+
+          case "&&" | "||" =>
+            // Logical operators.
             val lhs = walkTerm(l, envVarName)
             val rhs = walkTerm(r, envVarName)
             val rt  = findReturnType(lhs)
diff --git a/ultraviolet/shared/src/test/scala/ultraviolet/acceptance/GLSLIfStatementTests.scala b/ultraviolet/shared/src/test/scala/ultraviolet/acceptance/GLSLIfStatementTests.scala
index 5d5c646..1213324 100644
--- a/ultraviolet/shared/src/test/scala/ultraviolet/acceptance/GLSLIfStatementTests.scala
+++ b/ultraviolet/shared/src/test/scala/ultraviolet/acceptance/GLSLIfStatementTests.scala
@@ -371,4 +371,30 @@ class GLSLIfStatementTests extends munit.FunSuite {
     )
   }
 
+  test("if statement with not operator comparison") {
+    inline def fragment: Shader[FragEnv, vec4] =
+      Shader { _ =>
+        val x = 1.0f
+        if x != 2.0f then vec4(10.0f) else vec4(20.0f)
+      }
+
+    val actual =
+      fragment.toGLSL[WebGL2].toOutput.code
+
+    // DebugAST.toAST(fragment)
+    // println(actual)
+
+    assertEquals(
+      actual,
+      s"""
+      |float x=1.0;
+      |if(x!=2.0){
+      |  vec4(10.0);
+      |}else{
+      |  vec4(20.0);
+      |}
+      |""".stripMargin.trim
+    )
+  }
+
 }