internal/testing: bug fix: considering the case when Y is inverted

Closes #2003

internal/atlas/shader_test.go

@@ -21,6 +21,7 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/affine"
 	"github.com/hajimehoshi/ebiten/v2/internal/atlas"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
+	"github.com/hajimehoshi/ebiten/v2/internal/graphicscommand"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
 	etesting "github.com/hajimehoshi/ebiten/v2/internal/testing"
 )
@@ -38,13 +39,13 @@ func TestShaderFillTwice(t *testing.T) {
 		Width:  w,
 		Height: h,
 	}
-	p0 := etesting.ShaderProgramFill(0xff, 0xff, 0xff, 0xff)
+	p0 := etesting.ShaderProgramFill(graphicscommand.NeedsInvertY(), 0xff, 0xff, 0xff, 0xff)
 	s0 := atlas.NewShader(&p0)
 	dst.DrawTriangles([graphics.ShaderImageNum]*atlas.Image{}, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeCopy, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, dr, graphicsdriver.Region{}, [graphics.ShaderImageNum - 1][2]float32{}, s0, nil, false)
 
 	// Vertices must be recreated (#1755)
 	vs = quadVertices(w, h, 0, 0, 1)
-	p1 := etesting.ShaderProgramFill(0x80, 0x80, 0x80, 0xff)
+	p1 := etesting.ShaderProgramFill(graphicscommand.NeedsInvertY(), 0x80, 0x80, 0x80, 0xff)
 	s1 := atlas.NewShader(&p1)
 	dst.DrawTriangles([graphics.ShaderImageNum]*atlas.Image{}, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeCopy, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, dr, graphicsdriver.Region{}, [graphics.ShaderImageNum - 1][2]float32{}, s1, nil, false)
 

internal/graphicscommand/command.go

@@ -32,6 +32,10 @@ func SetGraphicsDriver(driver graphicsdriver.Graphics) {
 	theGraphicsDriver = driver
 }
 
+func NeedsInvertY() bool {
+	return theGraphicsDriver.FramebufferYDirection() != theGraphicsDriver.NDCYDirection()
+}
+
 func NeedsRestoring() bool {
 	return theGraphicsDriver.NeedsRestoring()
 }

internal/graphicscommand/image_test.go

@@ -103,7 +103,7 @@ func TestShader(t *testing.T) {
 	}
 	dst.DrawTriangles([graphics.ShaderImageNum]*graphicscommand.Image{clr}, [graphics.ShaderImageNum - 1][2]float32{}, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeClear, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, dr, graphicsdriver.Region{}, nil, nil, false)
 
-	ir := etesting.ShaderProgramFill(0xff, 0, 0, 0xff)
+	ir := etesting.ShaderProgramFill(graphicscommand.NeedsInvertY(), 0xff, 0, 0, 0xff)
 	s := graphicscommand.NewShader(&ir)
 	dst.DrawTriangles([graphics.ShaderImageNum]*graphicscommand.Image{}, [graphics.ShaderImageNum - 1][2]float32{}, vs, is, affine.ColorMIdentity{}, graphicsdriver.CompositeModeSourceOver, graphicsdriver.FilterNearest, graphicsdriver.AddressUnsafe, dr, graphicsdriver.Region{}, s, nil, false)
 

internal/restorable/images_test.go

@@ -23,12 +23,12 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
 	"github.com/hajimehoshi/ebiten/v2/internal/restorable"
-	t "github.com/hajimehoshi/ebiten/v2/internal/testing"
+	etesting "github.com/hajimehoshi/ebiten/v2/internal/testing"
 )
 
 func TestMain(m *testing.M) {
 	restorable.EnableRestoringForTesting()
-	t.MainWithRunLoop(m)
+	etesting.MainWithRunLoop(m)
 }
 
 func pixelsToColor(p *restorable.Pixels, i, j int) color.RGBA {

internal/restorable/shader_test.go

@@ -20,6 +20,7 @@ import (
 
 	"github.com/hajimehoshi/ebiten/v2/internal/affine"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphics"
+	"github.com/hajimehoshi/ebiten/v2/internal/graphicscommand"
 	"github.com/hajimehoshi/ebiten/v2/internal/graphicsdriver"
 	"github.com/hajimehoshi/ebiten/v2/internal/restorable"
 	etesting "github.com/hajimehoshi/ebiten/v2/internal/testing"
@@ -57,7 +58,7 @@ func TestShader(t *testing.T) {
 	img := restorable.NewImage(1, 1)
 	defer img.Dispose()
 
-	ir := etesting.ShaderProgramFill(0xff, 0, 0, 0xff)
+	ir := etesting.ShaderProgramFill(graphicscommand.NeedsInvertY(), 0xff, 0, 0, 0xff)
 	s := restorable.NewShader(&ir)
 	dr := graphicsdriver.Region{
 		X:      0,
@@ -92,7 +93,7 @@ func TestShaderChain(t *testing.T) {
 
 	imgs[0].ReplacePixels([]byte{0xff, 0, 0, 0xff}, 0, 0, 1, 1)
 
-	ir := etesting.ShaderProgramImages(1)
+	ir := etesting.ShaderProgramImages(graphicscommand.NeedsInvertY(), 1)
 	s := restorable.NewShader(&ir)
 	for i := 0; i < num-1; i++ {
 		dr := graphicsdriver.Region{
@@ -131,7 +132,7 @@ func TestShaderMultipleSources(t *testing.T) {
 
 	dst := restorable.NewImage(1, 1)
 
-	ir := etesting.ShaderProgramImages(3)
+	ir := etesting.ShaderProgramImages(graphicscommand.NeedsInvertY(), 3)
 	s := restorable.NewShader(&ir)
 	var offsets [graphics.ShaderImageNum - 1][2]float32
 	dr := graphicsdriver.Region{
@@ -170,7 +171,7 @@ func TestShaderMultipleSourcesOnOneTexture(t *testing.T) {
 
 	dst := restorable.NewImage(1, 1)
 
-	ir := etesting.ShaderProgramImages(3)
+	ir := etesting.ShaderProgramImages(graphicscommand.NeedsInvertY(), 3)
 	s := restorable.NewShader(&ir)
 	offsets := [graphics.ShaderImageNum - 1][2]float32{
 		{1, 0},
@@ -205,7 +206,7 @@ func TestShaderDispose(t *testing.T) {
 	img := restorable.NewImage(1, 1)
 	defer img.Dispose()
 
-	ir := etesting.ShaderProgramFill(0xff, 0, 0, 0xff)
+	ir := etesting.ShaderProgramFill(graphicscommand.NeedsInvertY(), 0xff, 0, 0, 0xff)
 	s := restorable.NewShader(&ir)
 	dr := graphicsdriver.Region{
 		X:      0,

internal/testing/shader.go

@@ -21,8 +21,17 @@ import (
 	"github.com/hajimehoshi/ebiten/v2/internal/shaderir"
 )
 
-var (
+func projectionMatrix(invertY bool) shaderir.Expr {
-	projectionMatrix = shaderir.Expr{
+	m11s := 1
+	if invertY {
+		m11s = -1
+	}
+	m31 := -1
+	if invertY {
+		m31 = 1
+	}
+
+	return shaderir.Expr{
 		Type: shaderir.Call,
 		Exprs: []shaderir.Expr{
 			{
@@ -79,7 +88,7 @@ var (
 				Exprs: []shaderir.Expr{
 					{
 						Type:      shaderir.NumberExpr,
-						Const:     constant.MakeFloat64(2),
+						Const:     constant.MakeFloat64(float64(m11s) * 2),
 						ConstType: shaderir.ConstTypeFloat,
 					},
 					{
@@ -134,7 +143,7 @@ var (
 			},
 			{
 				Type:      shaderir.NumberExpr,
-				Const:     constant.MakeFloat64(-1),
+				Const:     constant.MakeFloat64(float64(m31)),
 				ConstType: shaderir.ConstTypeFloat,
 			},
 			{
@@ -149,7 +158,10 @@ var (
 			},
 		},
 	}
-	vertexPosition = shaderir.Expr{
+}
+
+func vertexPosition() shaderir.Expr {
+	return shaderir.Expr{
 		Type: shaderir.Call,
 		Exprs: []shaderir.Expr{
 			{
@@ -172,7 +184,10 @@ var (
 			},
 		},
 	}
-	defaultVertexFunc = shaderir.VertexFunc{
+}
+
+func defaultVertexFunc(invertY bool) shaderir.VertexFunc {
+	return shaderir.VertexFunc{
 		Block: &shaderir.Block{
 			LocalVarIndexOffset: 4 + 1,
 			Stmts: []shaderir.Stmt{
@@ -200,8 +215,8 @@ var (
 							Type: shaderir.Binary,
 							Op:   shaderir.Mul,
 							Exprs: []shaderir.Expr{
-								projectionMatrix,
+								projectionMatrix(invertY),
-								vertexPosition,
+								vertexPosition(),
 							},
 						},
 					},
@@ -209,9 +224,9 @@ var (
 			},
 		},
 	}
-)
+}
 
-func defaultProgram() shaderir.Program {
+func defaultProgram(invertY bool) shaderir.Program {
 	p := shaderir.Program{
 		Attributes: []shaderir.Type{
 			{Main: shaderir.Vec2}, // Local var (0) in the vertex shader
@@ -221,7 +236,7 @@ func defaultProgram() shaderir.Program {
 		Varyings: []shaderir.Type{
 			{Main: shaderir.Vec2}, // Local var (4) in the vertex shader, (1) in the fragment shader
 		},
-		VertexFunc: defaultVertexFunc,
+		VertexFunc: defaultVertexFunc(invertY),
 	}
 
 	p.Uniforms = make([]shaderir.Type, graphics.PreservedUniformVariablesNum)
@@ -255,7 +270,7 @@ func defaultProgram() shaderir.Program {
 // Uniform variable's index and its value are:
 //
 //   0: the framebuffer size (Vec2)
-func ShaderProgramFill(r, g, b, a byte) shaderir.Program {
+func ShaderProgramFill(invertY bool, r, g, b, a byte) shaderir.Program {
 	clr := shaderir.Expr{
 		Type: shaderir.Call,
 		Exprs: []shaderir.Expr{
@@ -286,7 +301,7 @@ func ShaderProgramFill(r, g, b, a byte) shaderir.Program {
 		},
 	}
 
-	p := defaultProgram()
+	p := defaultProgram(invertY)
 	p.FragmentFunc = shaderir.FragmentFunc{
 		Block: &shaderir.Block{
 			LocalVarIndexOffset: 2 + 1,
@@ -315,12 +330,12 @@ func ShaderProgramFill(r, g, b, a byte) shaderir.Program {
 //   0:  the framebuffer size (Vec2)
 //
 // The size and region values are actually not used in this shader so far.
-func ShaderProgramImages(imageNum int) shaderir.Program {
+func ShaderProgramImages(invertY bool, imageNum int) shaderir.Program {
 	if imageNum <= 0 {
 		panic("testing: imageNum must be >= 1")
 	}
 
-	p := defaultProgram()
+	p := defaultProgram(invertY)
 	p.TextureNum = imageNum
 
 	// In the fragment shader, local variables are:

internal/ui/init.go

@@ -19,5 +19,10 @@ import (
 )
 
 func init() {
+	// TODO: Should graphics() be moved to the graphicscommand package?
 	graphicscommand.SetGraphicsDriver(graphics())
 }
+
+func NeedsInvertY() bool {
+	return graphicscommand.NeedsInvertY()
+}

internal/ui/ui.go

@@ -67,7 +67,3 @@ const (
 	WindowResizingModeOnlyFullscreenEnabled
 	WindowResizingModeEnabled
 )
-
-func NeedsInvertY() bool {
-	return graphics().FramebufferYDirection() != graphics().NDCYDirection()
-}