Revert "ebiten: panic if a non-existent uniform variable name is given"

This reverts commit 1b8580fab7.

Reason: some existing applications don't work with this fix.

Updates #2710

image.go

@@ -582,8 +582,6 @@ var _ [len(DrawTrianglesShaderOptions{}.Images) - graphics.ShaderImageCount]stru
 //
 // If a specified uniform variable's length or type doesn't match with an expected one, DrawTrianglesShader panics.
 //
-// If a non-existent uniform variable name is specified, DrawTrianglesShader panics.
-//
 // When the image i is disposed, DrawTrianglesShader does nothing.
 func (i *Image) DrawTrianglesShader(vertices []Vertex, indices []uint16, shader *Shader, options *DrawTrianglesShaderOptions) {
 	i.copyCheck()
@@ -736,8 +734,6 @@ var _ [len(DrawRectShaderOptions{}.Images)]struct{} = [graphics.ShaderImageCount
 //
 // If a specified uniform variable's length or type doesn't match with an expected one, DrawRectShader panics.
 //
-// If a non-existent uniform variable name is specified, DrawRectShader panics.
-//
 // In a shader, texCoord in Fragment represents a position in a source image.
 // If no source images are specified, texCoord represents the position from (0, 0) to (width, height) in pixels.
 // If the unit is pixels by a compiler directive `//kage:unit pixelss`, texCoord values are valid.

internal/ui/shader.go

@@ -46,22 +46,6 @@ func (s *Shader) MarkDisposed() {
 }
 
 func (s *Shader) AppendUniforms(dst []uint32, uniforms map[string]any) []uint32 {
-	// Check the given names are valid.
-	// This is a linear search and not efficient, but the number of uniform variables should not be so big.
-	for n := range uniforms {
-		var found bool
-		for _, nn := range s.uniformNames {
-			if n == nn {
-				found = true
-				break
-			}
-		}
-		if found {
-			continue
-		}
-		panic(fmt.Sprintf("ui: unexpected uniform name: %s", n))
-	}
-
 	if s.uniformUint32Count == 0 {
 		for _, typ := range s.uniformTypes {
 			s.uniformUint32Count += typ.Uint32Count()
@@ -82,6 +66,7 @@ func (s *Shader) AppendUniforms(dst []uint32, uniforms map[string]any) []uint32
 	for i, name := range s.uniformNames {
 		typ := s.uniformTypes[i]
 
+		// Ignore if an unused name is specified (#2710).
 		if uv, ok := uniforms[name]; ok {
 			v := reflect.ValueOf(uv)
 			t := v.Type()

shader_test.go

@@ -1942,18 +1942,6 @@ func Fragment(position vec4, texCoord vec2, color vec4) vec4 {
 			},
 			err: true,
 		},
-		{
-			uniforms: map[string]any{
-				"W": 1,
-			},
-			err: true,
-		},
-		{
-			uniforms: map[string]any{
-				"W": []int32{1, 2, 3},
-			},
-			err: true,
-		},
 	}
 	for _, tc := range tests {
 		tc := tc