Feature: Even more cases where math results can be precalculated.

Author: DeanEdisGG

ShaderShrinker/Shrinker.Parser/Optimizations/PerformArithmeticExtension.cs

@@ -354,6 +354,12 @@ private static bool IsSafeToPerformMath(SyntaxNode lhsNumNode, SymbolOperatorTok
                 case TokenExtensions.MathSymbolType.AddSubtract:
                     var prevSymbol = (lhsNumNode.Previous as GenericSyntaxNode)?.Token as SymbolOperatorToken;
                     var nextSymbol = (rhsNumNode.Next is RoundBracketSyntaxNode ? rhsNumNode.Next.Next : rhsNumNode.Next)?.Token as SymbolOperatorToken;
+
+                    if (prevSymbol?.GetMathSymbolType() == TokenExtensions.MathSymbolType.Unknown)
+                        prevSymbol = null;
+                    if (nextSymbol?.GetMathSymbolType() == TokenExtensions.MathSymbolType.Unknown)
+                        nextSymbol = null;
+
                     return new[] { prevSymbol, nextSymbol }.Where(o => o != null).All(o => o.GetMathSymbolType() == symbolType);
 
                 default:

ShaderShrinker/UnitTests/TestFiles/SimplifiedReference/Subway.glsl

@@ -1,4 +1,4 @@
-// Processed by 'GLSL Shader Shrinker' (Shrunk by 1,318 characters)
+// Processed by 'GLSL Shader Shrinker' (Shrunk by 1,322 characters)
 // (https://github.com/deanthecoder/GLSLShaderShrinker)
 
 #define MY_GPU_CAN_TAKE_IT
@@ -79,7 +79,7 @@ vec2 sdStep(vec3 p) {
 	float d2,
 	      d1 = sdBox(p, vec3(1.4, .02, .02));
 	if (d1 > 1.) return vec2(d1, 3.5);
-	p.y += .16 + .02;
+	p.y += .18;
 	d2 = sdBox(p, vec3(1.385, .145, .02));
 	d1 = min(d1, sdBox(p - vec3(0, 0, .015), vec3(1.4, .16, .02)));
 	p.yz += vec2(.18, .32);

ShaderShrinker/UnitTests/TestFiles/SimplifiedReference/Temple.glsl

@@ -1,4 +1,4 @@
-// Processed by 'GLSL Shader Shrinker' (Shrunk by 408 characters)
+// Processed by 'GLSL Shader Shrinker' (Shrunk by 412 characters)
 // (https://github.com/deanthecoder/GLSLShaderShrinker)
 
 #define SKYCOL	vec3(.6, .8, .9)
@@ -48,12 +48,12 @@ float sdTempleColumn(vec3 p) {
 	d = sdColumn(p, r);
 	{
 		vec3 q = p;
-		q.y -= 4. + .16;
+		q.y -= 4.16;
 		d = min(d, sdCube(q, vec3(.7, .16, .7)) - .05);
 	}
 	{
 		vec3 q = p;
-		q.y += 4. - .4;
+		q.y += 3.6;
 		d = min(d, sdCube(q, vec3(.7, .16, .7)) - .05);
 	}
 	return d;

ShaderShrinker/UnitTests/VectorArithmeticTests.cs

@@ -238,7 +238,8 @@ public void CheckArithmeticWithVectorAndScalar(
                     "vec2 main() { return 1. + 3. * vec2(1, 2); }",
                     "vec2 main() { return 1. + vec2(1, 2) * 3.; }",
                     "vec2 main() { return vec2(21, 22) / 7.; }",
-                    "vec3 main() { vec3 v = vec3(.4); float k = 1.; return (v + vec3(.6, .8, 1) * .5 * k) / (1. + k); }")] string code,
+                    "vec3 main() { vec3 v = vec3(.4); float k = 1.; return (v + vec3(.6, .8, 1) * .5 * k) / (1. + k); }",
+                    "p.xy -= 5. * vec2(0.64, 0.7) - 2.5;")] string code,
             [Values("vec2 f = vec2(4.4, 5.5);",
                     "vec3 f = vec3(-3.3, -2.2, -1.1);",
                     "vec4 f = vec4(2.42);",
@@ -258,7 +259,8 @@ public void CheckArithmeticWithVectorAndScalar(
                     "vec2 main() { return vec2(4, 7); }",
                     "vec2 main() { return vec2(4, 7); }",
                     "vec2 main() { return vec2(21, 22) / 7.; }",
-                    "vec3 main() { vec3 v = vec3(.4); float k = 1.; return (v + vec3(.3, .4, .5) * k) / (1. + k); }")] string expected)
+                    "vec3 main() { vec3 v = vec3(.4); float k = 1.; return (v + vec3(.3, .4, .5) * k) / (1. + k); }",
+                    "p.xy -= vec2(.7, 1);")] string expected)
         {
             var lexer = new Lexer();
             lexer.Load(code);