internal/shader: refactoring

image.go

@@ -18,6 +18,7 @@ import (
 	"fmt"
 	"image"
 	"image/color"
+	"unsafe"
 
 	"github.com/hajimehoshi/ebiten/v2/internal/affine"
 	"github.com/hajimehoshi/ebiten/v2/internal/atlas"
@@ -296,6 +297,8 @@ type Vertex struct {
 	ColorA float32
 }
 
+var _ [0]byte = [unsafe.Sizeof(Vertex{}) - unsafe.Sizeof(float32(0))*graphics.VertexFloatCount]byte{}
+
 // Address represents a sampler address mode.
 type Address int
 

internal/shader/shader.go

@@ -56,11 +56,11 @@ type compileState struct {
 	ir shaderir.Program
 
 	funcs            []function
+	vertexOutParams  []shaderir.Type
+	fragmentInParams []shaderir.Type
 
 	global block
 
-	varyingParsed bool
-
 	errs []string
 }
 
@@ -348,6 +348,29 @@ func (cs *compileState) parse(f *ast.File) {
 		return
 	}
 
+	// Parse varying veraibles.
+	// In testings, there might not be vertex and fragment entry points.
+	if cs.ir.VertexFunc.Block != nil && cs.ir.FragmentFunc.Block != nil {
+		if len(cs.fragmentInParams) != len(cs.vertexOutParams) {
+			cs.addError(0, "the number of vertex entry point's returning values and the number of fragment entry point's params must be the same")
+		}
+		for i, t := range cs.vertexOutParams {
+			if !t.Equal(&cs.fragmentInParams[i]) {
+				cs.addError(0, "vertex entry point's returning value types and fragment entry point's param types must match")
+			}
+		}
+	}
+
+	if cs.ir.VertexFunc.Block != nil {
+		// TODO: Check that these params are not arrays or structs
+		// The 0th argument is a special variable for position and is not included in varying variables.
+		cs.ir.Varyings = append(cs.ir.Varyings, cs.vertexOutParams[1:]...)
+	}
+
+	if len(cs.errs) > 0 {
+		return
+	}
+
 	for _, f := range cs.funcs {
 		cs.ir.Funcs = append(cs.ir.Funcs, f.ir)
 	}
@@ -460,8 +483,10 @@ func (cs *compileState) parseDecl(b *block, fname string, d ast.Decl) ([]shaderi
 		switch d.Name.Name {
 		case cs.vertexEntry:
 			cs.ir.VertexFunc.Block = f.ir.Block
+			cs.vertexOutParams = f.ir.OutParams
 		case cs.fragmentEntry:
 			cs.ir.FragmentFunc.Block = f.ir.Block
+			cs.fragmentInParams = f.ir.InParams
 		default:
 			// The function is already registered for their names.
 			for i := range cs.funcs {
@@ -767,18 +792,6 @@ func (cs *compileState) parseFunc(block *block, d *ast.FuncDecl) (function, bool
 
 	inParams, outParams, returnType := cs.parseFuncParams(block, d.Name.Name, d)
 
-	checkVaryings := func(vs []variable) {
-		if len(cs.ir.Varyings) != len(vs) {
-			cs.addError(d.Pos(), "the number of vertex entry point's returning values and the number of fragment entry point's params must be the same")
-			return
-		}
-		for i, t := range cs.ir.Varyings {
-			if t.Main != vs[i].typ.Main {
-				cs.addError(d.Pos(), "vertex entry point's returning value types and fragment entry point's param types must match")
-			}
-		}
-	}
-
 	if block == &cs.global {
 		switch d.Name.Name {
 		case cs.vertexEntry:
@@ -802,15 +815,6 @@ func (cs *compileState) parseFunc(block *block, d *ast.FuncDecl) (function, bool
 				return function{}, false
 			}
 
-			if cs.varyingParsed {
-				checkVaryings(outParams[1:])
-			} else {
-				for _, v := range outParams[1:] {
-					// TODO: Check that these params are not arrays or structs
-					cs.ir.Varyings = append(cs.ir.Varyings, v.typ)
-				}
-			}
-			cs.varyingParsed = true
 		case cs.fragmentEntry:
 			if len(inParams) == 0 {
 				cs.addError(d.Pos(), "fragment entry point must have at least one vec4 parameter for a position")
@@ -825,15 +829,6 @@ func (cs *compileState) parseFunc(block *block, d *ast.FuncDecl) (function, bool
 				cs.addError(d.Pos(), "fragment entry point must have one returning vec4 value for a color")
 				return function{}, false
 			}
-
-			if cs.varyingParsed {
-				checkVaryings(inParams[1:])
-			} else {
-				for _, v := range inParams[1:] {
-					cs.ir.Varyings = append(cs.ir.Varyings, v.typ)
-				}
-			}
-			cs.varyingParsed = true
 		}
 	}
 

internal/shaderir/type.go

@@ -25,7 +25,7 @@ type Type struct {
 	Length int
 }
 
-func (t *Type) Equal(rhs *Type) bool {
+func (t Type) Equal(rhs *Type) bool {
 	if t.Main != rhs.Main {
 		return false
 	}
@@ -43,7 +43,7 @@ func (t *Type) Equal(rhs *Type) bool {
 	return true
 }
 
-func (t *Type) String() string {
+func (t Type) String() string {
 	switch t.Main {
 	case None:
 		return "none"
@@ -87,7 +87,7 @@ func (t *Type) String() string {
 	}
 }
 
-func (t *Type) Uint32Count() int {
+func (t Type) Uint32Count() int {
 	switch t.Main {
 	case Int:
 		return 1
@@ -118,7 +118,7 @@ func (t *Type) Uint32Count() int {
 	}
 }
 
-func (t *Type) IsFloatVector() bool {
+func (t Type) IsFloatVector() bool {
 	switch t.Main {
 	case Vec2, Vec3, Vec4:
 		return true
@@ -126,7 +126,7 @@ func (t *Type) IsFloatVector() bool {
 	return false
 }
 
-func (t *Type) IsIntVector() bool {
+func (t Type) IsIntVector() bool {
 	switch t.Main {
 	case IVec2, IVec3, IVec4:
 		return true
@@ -134,7 +134,7 @@ func (t *Type) IsIntVector() bool {
 	return false
 }
 
-func (t *Type) VectorElementCount() int {
+func (t Type) VectorElementCount() int {
 	switch t.Main {
 	case Vec2:
 		return 2
@@ -153,7 +153,7 @@ func (t *Type) VectorElementCount() int {
 	}
 }
 
-func (t *Type) IsMatrix() bool {
+func (t Type) IsMatrix() bool {
 	switch t.Main {
 	case Mat2, Mat3, Mat4:
 		return true