all: remove Z buffer support

It is no longer needed by any rendering backend.

Signed-off-by: Elias Naur <mail@eliasnaur.com>

app/internal/wm/d3d11_windows.go

@@ -17,7 +17,6 @@ type d3d11Context struct {
 
 	swchain       *d3d11.IDXGISwapChain
 	renderTarget  *d3d11.RenderTargetView
-	depthView     *d3d11.DepthStencilView
 	width, height int
 }
 
@@ -56,8 +55,7 @@ func (c *d3d11Context) API() gpu.API {
 
 func (c *d3d11Context) RenderTarget() gpu.RenderTarget {
 	return gpu.Direct3D11RenderTarget{
-		RenderTarget:     unsafe.Pointer(c.renderTarget),
-		DepthStencilView: unsafe.Pointer(c.depthView),
+		RenderTarget: unsafe.Pointer(c.renderTarget),
 	}
 }
 
@@ -91,10 +89,6 @@ func (c *d3d11Context) Refresh() error {
 	c.width = width
 	c.height = height
 
-	desc, err := c.swchain.GetDesc()
-	if err != nil {
-		return err
-	}
 	backBuffer, err := c.swchain.GetBuffer(0, &d3d11.IID_Texture2D)
 	if err != nil {
 		return err
@@ -105,18 +99,12 @@ func (c *d3d11Context) Refresh() error {
 	if err != nil {
 		return err
 	}
-	depthView, err := d3d11.CreateDepthView(c.dev, int(desc.BufferDesc.Width), int(desc.BufferDesc.Height), 24)
-	if err != nil {
-		d3d11.IUnknownRelease(unsafe.Pointer(renderTarget), renderTarget.Vtbl.Release)
-		return err
-	}
 	c.renderTarget = renderTarget
-	c.depthView = depthView
 	return nil
 }
 
 func (c *d3d11Context) Lock() error {
-	c.ctx.OMSetRenderTargets(c.renderTarget, c.depthView)
+	c.ctx.OMSetRenderTargets(c.renderTarget, nil)
 	return nil
 }
 
@@ -140,10 +128,6 @@ func (c *d3d11Context) Release() {
 }
 
 func (c *d3d11Context) releaseFBO() {
-	if c.depthView != nil {
-		d3d11.IUnknownRelease(unsafe.Pointer(c.depthView), c.depthView.Vtbl.Release)
-		c.depthView = nil
-	}
 	if c.renderTarget != nil {
 		d3d11.IUnknownRelease(unsafe.Pointer(c.renderTarget), c.renderTarget.Vtbl.Release)
 		c.renderTarget = nil

app/internal/wm/gl_ios.go

@@ -27,13 +27,13 @@ import (
 )
 
 type context struct {
-	owner                    *window
-	c                        *gl.Functions
-	ctx                      C.CFTypeRef
-	layer                    C.CFTypeRef
-	init                     bool
-	frameBuffer              gl.Framebuffer
-	colorBuffer, depthBuffer gl.Renderbuffer
+	owner       *window
+	c           *gl.Functions
+	ctx         C.CFTypeRef
+	layer       C.CFTypeRef
+	init        bool
+	frameBuffer gl.Framebuffer
+	colorBuffer gl.Renderbuffer
 }
 
 func init() {
@@ -80,7 +80,6 @@ func (c *context) Release() {
 	C.gio_renderbufferStorage(c.ctx, 0, C.GLenum(gl.RENDERBUFFER))
 	c.c.DeleteFramebuffer(c.frameBuffer)
 	c.c.DeleteRenderbuffer(c.colorBuffer)
-	c.c.DeleteRenderbuffer(c.depthBuffer)
 	C.gio_makeCurrent(0)
 	C.CFRelease(c.ctx)
 	c.ctx = 0
@@ -90,10 +89,6 @@ func (c *context) Present() error {
 	if c.layer == 0 {
 		panic("context is not active")
 	}
-	// Discard depth buffer as recommended in
-	// https://developer.apple.com/library/archive/documentation/3DDrawing/Conceptual/OpenGLES_ProgrammingGuide/WorkingwithEAGLContexts/WorkingwithEAGLContexts.html
-	c.c.BindFramebuffer(gl.FRAMEBUFFER, c.frameBuffer)
-	c.c.InvalidateFramebuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT)
 	c.c.BindRenderbuffer(gl.RENDERBUFFER, c.colorBuffer)
 	if C.gio_presentRenderbuffer(c.ctx, C.GLenum(gl.RENDERBUFFER)) == 0 {
 		return errors.New("presentRenderBuffer failed")
@@ -120,7 +115,6 @@ func (c *context) Refresh() error {
 		c.init = true
 		c.frameBuffer = c.c.CreateFramebuffer()
 		c.colorBuffer = c.c.CreateRenderbuffer()
-		c.depthBuffer = c.c.CreateRenderbuffer()
 	}
 	if !c.owner.isVisible() {
 		// Make sure any in-flight GL commands are complete.
@@ -132,14 +126,9 @@ func (c *context) Refresh() error {
 	if C.gio_renderbufferStorage(c.ctx, c.layer, C.GLenum(gl.RENDERBUFFER)) == 0 {
 		return errors.New("renderbufferStorage failed")
 	}
-	w := c.c.GetRenderbufferParameteri(gl.RENDERBUFFER, gl.RENDERBUFFER_WIDTH)
-	h := c.c.GetRenderbufferParameteri(gl.RENDERBUFFER, gl.RENDERBUFFER_HEIGHT)
-	c.c.BindRenderbuffer(gl.RENDERBUFFER, c.depthBuffer)
-	c.c.RenderbufferStorage(gl.RENDERBUFFER, gl.DEPTH_COMPONENT16, w, h)
 	c.c.BindRenderbuffer(gl.RENDERBUFFER, currentRB)
 	c.c.BindFramebuffer(gl.FRAMEBUFFER, c.frameBuffer)
 	c.c.FramebufferRenderbuffer(gl.FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.RENDERBUFFER, c.colorBuffer)
-	c.c.FramebufferRenderbuffer(gl.FRAMEBUFFER, gl.DEPTH_ATTACHMENT, gl.RENDERBUFFER, c.depthBuffer)
 	if st := c.c.CheckFramebufferStatus(gl.FRAMEBUFFER); st != gl.FRAMEBUFFER_COMPLETE {
 		return fmt.Errorf("framebuffer incomplete, status: %#x\n", st)
 	}

app/internal/wm/gl_macos.m

@@ -13,7 +13,6 @@ CFTypeRef gio_createGLContext(void) {
 		NSOpenGLPixelFormatAttribute attr[] = {
 			NSOpenGLPFAOpenGLProfile, NSOpenGLProfileVersion3_2Core,
 			NSOpenGLPFAColorSize,     24,
-			NSOpenGLPFADepthSize,     16,
 			NSOpenGLPFAAccelerated,
 			// Opt-in to automatic GPU switching. CGL-only property.
 			kCGLPFASupportsAutomaticGraphicsSwitching,