From e52ee3ba9a59ebff7477099bbe791e39406fa8d9 Mon Sep 17 00:00:00 2001
From: faiface <faiface@ksp.sk>
Date: Wed, 23 Nov 2016 18:50:49 +0100
Subject: [PATCH] encapsulate error handling
add functions DoGLErr, DoErrGLErr and DoValGLErr to handle OpenGL errors
---
pixelgl/error.go | 41 --------------------------
pixelgl/texture.go | 4 +--
pixelgl/thread.go | 73 ++++++++++++++++++++++++++++++++++++++++++++--
pixelgl/vertex.go | 7 ++---
4 files changed, 74 insertions(+), 51 deletions(-)
delete mode 100644 pixelgl/error.go
diff --git a/pixelgl/error.go b/pixelgl/error.go
deleted file mode 100644
index 48e5e90..0000000
--- a/pixelgl/error.go
+++ /dev/null
@@ -1,41 +0,0 @@
-package pixelgl
-
-import (
- "github.com/go-gl/gl/v3.3-core/gl"
- "github.com/pkg/errors"
-)
-
-// getLastError returns (and consumes) the last error generated by OpenGL inside the current Do, DoErr or DoVal.
-// If no error has been generated, this function returns nil.
-//
-// Call this function only inside the OpenGL thread (Do, DoErr or DoVal function). It's not guaranteed
-// to work correctly outside of it, because the thread swallows extra unchecked errors.
-func getLastError() error {
- err := uint32(gl.NO_ERROR)
- for e := gl.GetError(); e != gl.NO_ERROR; e = gl.GetError() {
- err = e
- }
- if err == gl.NO_ERROR {
- return nil
- }
- switch err {
- case gl.INVALID_ENUM:
- return errors.New("invalid enum")
- case gl.INVALID_VALUE:
- return errors.New("invalid value")
- case gl.INVALID_OPERATION:
- return errors.New("invalid operation")
- case gl.STACK_OVERFLOW:
- return errors.New("stack overflow")
- case gl.STACK_UNDERFLOW:
- return errors.New("stack underflow")
- case gl.OUT_OF_MEMORY:
- return errors.New("out of memory")
- case gl.INVALID_FRAMEBUFFER_OPERATION:
- return errors.New("invalid framebuffer operation")
- case gl.CONTEXT_LOST:
- return errors.New("context lost")
- default:
- return errors.New("unknown error")
- }
-}
diff --git a/pixelgl/texture.go b/pixelgl/texture.go
index 7d02e5e..d9cad7b 100644
--- a/pixelgl/texture.go
+++ b/pixelgl/texture.go
@@ -15,7 +15,7 @@ type Texture struct {
// The pixels must be a sequence of RGBA values.
func NewTexture(parent BeginEnder, width, height int, pixels []uint8) (*Texture, error) {
texture := &Texture{parent: parent}
- err := DoErr(func() error {
+ err := DoGLErr(func() {
gl.GenTextures(1, &texture.tex)
gl.BindTexture(gl.TEXTURE_2D, texture.tex)
@@ -33,8 +33,6 @@ func NewTexture(parent BeginEnder, width, height int, pixels []uint8) (*Texture,
gl.GenerateMipmap(gl.TEXTURE_2D)
gl.BindTexture(gl.TEXTURE_2D, 0)
-
- return getLastError()
})
if err != nil {
return nil, errors.Wrap(err, "failed to create a texture")
diff --git a/pixelgl/thread.go b/pixelgl/thread.go
index 03597da..b4b5800 100644
--- a/pixelgl/thread.go
+++ b/pixelgl/thread.go
@@ -1,6 +1,11 @@
package pixelgl
-import "runtime"
+import (
+ "errors"
+ "runtime"
+
+ "github.com/go-gl/gl/v2.1/gl"
+)
// Due to the existance and usage of thread-local variables by OpenGL, it's recommended to
// execute all OpenGL calls from a single dedicated thread. This file defines functions to make
@@ -16,7 +21,7 @@ func init() {
go func() {
runtime.LockOSThread()
for f := range callQueue {
- getLastError() // swallow unchecked errors
+ getLastGLErr() // swallow unchecked errors
f()
}
}()
@@ -58,3 +63,67 @@ func DoVal(f func() interface{}) interface{} {
}
return <-val
}
+
+// DoGLErr is same as Do, but also return an error generated by OpenGL.
+func DoGLErr(f func()) (gl error) {
+ glerr := make(chan error)
+ callQueue <- func() {
+ f()
+ glerr <- getLastGLErr()
+ }
+ return <-glerr
+}
+
+// DoErrGLErr is same as DoErr, but also returns an error generated by OpenGL.
+func DoErrGLErr(f func() error) (_, gl error) {
+ err := make(chan error)
+ glerr := make(chan error)
+ callQueue <- func() {
+ err <- f()
+ glerr <- getLastGLErr()
+ }
+ return <-err, <-glerr
+}
+
+// DoValGLErr is same as DoVal, but also returns an error generated by OpenGL.
+func DoValGLErr(f func() interface{}) (_ interface{}, gl error) {
+ val := make(chan interface{})
+ glerr := make(chan error)
+ callQueue <- func() {
+ val <- f()
+ glerr <- getLastGLErr()
+ }
+ return <-val, <-glerr
+}
+
+// getLastGLErr returns (and consumes) the last error generated by OpenGL.
+// Don't use outside DoGLErr, DoErrGLErr and DoValGLErr.
+func getLastGLErr() error {
+ err := uint32(gl.NO_ERROR)
+ for e := gl.GetError(); e != gl.NO_ERROR; e = gl.GetError() {
+ err = e
+ }
+ if err == gl.NO_ERROR {
+ return nil
+ }
+ switch err {
+ case gl.INVALID_ENUM:
+ return errors.New("invalid enum")
+ case gl.INVALID_VALUE:
+ return errors.New("invalid value")
+ case gl.INVALID_OPERATION:
+ return errors.New("invalid operation")
+ case gl.STACK_OVERFLOW:
+ return errors.New("stack overflow")
+ case gl.STACK_UNDERFLOW:
+ return errors.New("stack underflow")
+ case gl.OUT_OF_MEMORY:
+ return errors.New("out of memory")
+ case gl.INVALID_FRAMEBUFFER_OPERATION:
+ return errors.New("invalid framebuffer operation")
+ case gl.CONTEXT_LOST:
+ return errors.New("context lost")
+ default:
+ return errors.New("unknown error")
+ }
+}
diff --git a/pixelgl/vertex.go b/pixelgl/vertex.go
index 8c0c09d..63cc498 100644
--- a/pixelgl/vertex.go
+++ b/pixelgl/vertex.go
@@ -105,7 +105,7 @@ func NewVertexArray(parent BeginEnder, format VertexFormat, mode VertexDrawMode,
format: format,
mode: mode,
}
- err := DoErr(func() error {
+ err := DoGLErr(func() {
gl.GenVertexArrays(1, &va.vao)
gl.BindVertexArray(va.vao)
@@ -132,8 +132,6 @@ func NewVertexArray(parent BeginEnder, format VertexFormat, mode VertexDrawMode,
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
gl.BindVertexArray(0)
-
- return getLastError()
})
if err != nil {
return nil, errors.Wrap(err, "failed to create a vertex array")
@@ -173,11 +171,10 @@ func (va *VertexArray) Draw() {
//
// Offset is not a number of bytes, instead, it's an index in the array.
func (va *VertexArray) UpdateData(offset int, data []float64) error {
- err := DoErr(func() error {
+ err := DoGLErr(func() {
gl.BindBuffer(gl.ARRAY_BUFFER, va.vbo)
gl.BufferSubData(gl.ARRAY_BUFFER, 8*offset, 8*len(data), gl.Ptr(data))
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
- return getLastError()
})
if err != nil {
return errors.Wrap(err, "failed to update vertex array")
--
GitLab