ui/app: split extension string before matching

Avoids false matches for extensions whose names are substrings of
other extensions.

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

ui/app/egl.go

@@ -176,6 +176,15 @@ func (c *context) MakeCurrent() error {
 	return nil
 }
 
+func hasExtension(exts []string, ext string) bool {
+	for _, e := range exts {
+		if ext == e {
+			return true
+		}
+	}
+	return false
+}
+
 func createContext(disp _EGLNativeDisplayType) (*eglContext, error) {
 	eglDisp := eglGetDisplay(disp)
 	if eglDisp == 0 {
@@ -186,8 +195,8 @@ func createContext(disp _EGLNativeDisplayType) (*eglContext, error) {
 		return nil, fmt.Errorf("eglInitialize failed: 0x%x", eglGetError())
 	}
 	// sRGB framebuffer support on EGL 1.5 or if EGL_KHR_gl_colorspace is supported.
-	exts := eglQueryString(eglDisp, _EGL_EXTENSIONS)
+	exts := strings.Split(eglQueryString(eglDisp, _EGL_EXTENSIONS), " ")
-	srgb := minor >= 5 || strings.Contains(exts, "EGL_KHR_gl_colorspace")
+	srgb := minor >= 5 || hasExtension(exts, "EGL_KHR_gl_colorspace")
 	attribs := []_EGLint{
 		_EGL_RENDERABLE_TYPE, _EGL_OPENGL_ES2_BIT,
 		_EGL_SURFACE_TYPE, _EGL_WINDOW_BIT,

ui/app/internal/gpu/context.go

@@ -34,7 +34,7 @@ func newContext(glctx gl.Context) (*context, error) {
 	ctx := &context{
 		Functions: glctx.Functions(),
 	}
-	exts := ctx.GetString(gl.EXTENSIONS)
+	exts := strings.Split(ctx.GetString(gl.EXTENSIONS), " ")
 	glVer := ctx.GetString(gl.VERSION)
 	ver, err := gl.ParseGLVersion(glVer)
 	if err != nil {
@@ -49,7 +49,7 @@ func newContext(glctx gl.Context) (*context, error) {
 		return nil, err
 	}
 	ctx.caps = caps{
-		EXT_disjoint_timer_query: strings.Contains(exts, "GL_EXT_disjoint_timer_query"),
+		EXT_disjoint_timer_query: hasExtension(exts, "GL_EXT_disjoint_timer_query"),
 		floatTriple:              floatTriple,
 		alphaTriple:              alphaTripleFor(ver),
 		srgbaTriple:              srgbaTriple,
@@ -57,11 +57,11 @@ func newContext(glctx gl.Context) (*context, error) {
 	return ctx, nil
 }
 
-func srgbaTripleFor(ver [2]int, exts string) (textureTriple, error) {
+func srgbaTripleFor(ver [2]int, exts []string) (textureTriple, error) {
 	switch {
 	case ver[0] >= 3:
 		return textureTriple{gl.SRGB8_ALPHA8, gl.Enum(gl.RGBA), gl.Enum(gl.UNSIGNED_BYTE)}, nil
-	case strings.Contains(exts, "GL_EXT_sRGB"):
+	case hasExtension(exts, "GL_EXT_sRGB"):
 		return textureTriple{gl.SRGB_ALPHA_EXT, gl.Enum(gl.SRGB_ALPHA_EXT), gl.Enum(gl.UNSIGNED_BYTE)}, nil
 	default:
 		return textureTriple{}, errors.New("no sRGB texture formats found")
@@ -77,15 +77,24 @@ func alphaTripleFor(ver [2]int) textureTriple {
 	return textureTriple{intf, f, gl.UNSIGNED_BYTE}
 }
 
-func floatTripleFor(ver [2]int, exts string) (textureTriple, error) {
+func floatTripleFor(ver [2]int, exts []string) (textureTriple, error) {
 	switch {
 	case ver[0] >= 3:
 		return textureTriple{gl.R16F, gl.Enum(gl.RED), gl.Enum(gl.HALF_FLOAT)}, nil
-	case strings.Contains(exts, "GL_OES_texture_half_float"):
+	case hasExtension(exts, "GL_OES_texture_half_float") || hasExtension(exts, "EXT_color_buffer_half_float"):
 		return textureTriple{gl.RGBA, gl.Enum(gl.RGBA), gl.Enum(gl.HALF_FLOAT_OES)}, nil
-	case strings.Contains(exts, "GL_OES_texture_float"):
+	case hasExtension(exts, "GL_OES_texture_float") || hasExtension(exts, "GL_EXT_color_buffer_float"):
 		return textureTriple{gl.RGBA, gl.Enum(gl.RGBA), gl.Enum(gl.FLOAT)}, nil
 	default:
 		return textureTriple{}, errors.New("floating point texture not supported")
 	}
 }
+
+func hasExtension(exts []string, ext string) bool {
+	for _, e := range exts {
+		if ext == e {
+			return true
+		}
+	}
+	return false
+}