From 36759cc253dcb99d9d3462fb96485cee55821ac0 Mon Sep 17 00:00:00 2001
From: Babz <babz@tfnux.org>
Date: Sat, 16 Jan 2021 14:30:11 +0100
Subject: [PATCH 1/2] switch to GLES 3.1 (should improve compatibility)

---
 glc/buffer.go  |  2 +-
 glc/init.go    |  2 +-
 glc/program.go |  2 +-
 glc/shader.go  | 15 +++++++++++----
 glc/sync.go    |  2 +-
 go.mod         |  1 +
 go.sum         |  3 ++-
 7 files changed, 18 insertions(+), 9 deletions(-)

diff --git a/glc/buffer.go b/glc/buffer.go
index 5ee5226..799b6ef 100644
--- a/glc/buffer.go
+++ b/glc/buffer.go
@@ -5,7 +5,7 @@ import (
 	"runtime"
 	"unsafe"
 
-	"github.com/go-gl/gl/v4.3-core/gl"
+	gl "github.com/adraenwan/opengl-es-go/v3.1/gl"
 )
 
 // const (
diff --git a/glc/init.go b/glc/init.go
index 71ef0fc..b420b7f 100644
--- a/glc/init.go
+++ b/glc/init.go
@@ -1,7 +1,7 @@
 package glc
 
 import (
-	"github.com/go-gl/gl/v4.3-core/gl"
+	gl "github.com/adraenwan/opengl-es-go/v3.1/gl"
 	"github.com/remogatto/egl"
 
 	"fmt"
diff --git a/glc/program.go b/glc/program.go
index bc668b4..94b81d1 100644
--- a/glc/program.go
+++ b/glc/program.go
@@ -5,7 +5,7 @@ import (
 	"runtime"
 	"strings"
 
-	"github.com/go-gl/gl/v4.3-core/gl"
+	gl "github.com/adraenwan/opengl-es-go/v3.1/gl"
 )
 
 // Hight-level wrapper for shader programs
diff --git a/glc/shader.go b/glc/shader.go
index e88a197..a2a54b7 100644
--- a/glc/shader.go
+++ b/glc/shader.go
@@ -6,9 +6,15 @@ import (
 	"runtime"
 	"strings"
 
-	"github.com/go-gl/gl/v4.3-core/gl"
+	gl "github.com/adraenwan/opengl-es-go/v3.1/gl"
 )
 
+/*
+#include <stdlib.h>
+*/
+import "C"
+import "unsafe"
+
 // wrapper for shaders
 // not necessary since Program
 // handles the creation/deletion
@@ -58,10 +64,11 @@ func (s *Shader) check() error {
 }
 
 func (s *Shader) CompileStr(source string) error {
-	csource, csourceFree := gl.Strs(source)
-	defer csourceFree()
+	csource := C.CString(source)
+	defer C.free(unsafe.Pointer(csource))
+
 	ln := int32(len(source))
-	gl.ShaderSource(s.id, 1, csource, &ln)
+	gl.ShaderSource(s.id, 1, (**uint8)(unsafe.Pointer(&csource)), &ln)
 	gl.CompileShader(s.id)
 
 	err := s.check()
diff --git a/glc/sync.go b/glc/sync.go
index cc7ec13..c86adae 100644
--- a/glc/sync.go
+++ b/glc/sync.go
@@ -3,7 +3,7 @@ package glc
 import (
 	"time"
 
-	"github.com/go-gl/gl/v4.3-core/gl"
+	gl "github.com/adraenwan/opengl-es-go/v3.1/gl"
 )
 
 // memory barrier
diff --git a/go.mod b/go.mod
index c6a0a57..0f564d1 100644
--- a/go.mod
+++ b/go.mod
@@ -3,6 +3,7 @@ module github.com/adraenwan/glcompute
 go 1.15
 
 require (
+	github.com/adraenwan/opengl-es-go v0.0.0-20150603063834-39b7066af7c2
 	github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7
 	github.com/remogatto/egl v0.0.0-20140203134355-fea5ba3496ba
 )
diff --git a/go.sum b/go.sum
index 4780910..f9abddf 100644
--- a/go.sum
+++ b/go.sum
@@ -1,4 +1,5 @@
-github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7 h1:SCYMcCJ89LjRGwEa0tRluNRiMjZHalQZrVrvTbPh+qw=
+github.com/adraenwan/opengl-es-go v0.0.0-20150603063834-39b7066af7c2 h1:Yzm59/hcTu6zRrJzR5rmsuGiwB1g8jbHR4cIr9hwPKg=
+github.com/adraenwan/opengl-es-go v0.0.0-20150603063834-39b7066af7c2/go.mod h1:uSgZwepxb/uB8Sat8WRdDEr9uJ2N/0QUeQBm++q8YyU=
 github.com/go-gl/gl v0.0.0-20190320180904-bf2b1f2f34d7/go.mod h1:482civXOzJJCPzJ4ZOX/pwvXBWSnzD4OKMdH4ClKGbk=
 github.com/remogatto/egl v0.0.0-20140203134355-fea5ba3496ba h1:0EE2haDQAnaldV7OhCWqltUPcgsZUZttKOGcHKZyxdM=
 github.com/remogatto/egl v0.0.0-20140203134355-fea5ba3496ba/go.mod h1:/SxS0px6zZIo/owvUHed3K8JBZQ10aIpTdMOkjeWlmo=

From ab8367a6cf43bae304a962c7cdfd6d783bdc4422 Mon Sep 17 00:00:00 2001
From: Babz <babz@tfnux.org>
Date: Sat, 16 Jan 2021 15:23:24 +0100
Subject: [PATCH 2/2] readme : gl 4.3 -> gles 3.1

---
 README.md | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/README.md b/README.md
index e35b5a5..c78eb9b 100644
--- a/README.md
+++ b/README.md
@@ -1,7 +1,7 @@
 # GLcompute
 [![Documentation](https://godoc.org/github.com/adraenwan/glcompute?status.svg)](https://godoc.org/github.com/adraenwan/glcompute)
 
-GLcompute (aka glc) is a Go library  for GPGPU using OpenGL 4.3 compute shaders as the backend.
+GLcompute (aka glc) is a Go library  for GPGPU using OpenGL ES 3.1 compute shaders as the backend.
 
 * `glc/` contains the actual library
 * `demo/` contains a short example to get started with glc