diff --git a/graphics.go b/graphics.go
deleted file mode 100644
index 438167198c9fef294401c3dfc309f17f27d0f21f..0000000000000000000000000000000000000000
--- a/graphics.go
+++ /dev/null
@@ -1,58 +0,0 @@
-package pixel
-
-import "github.com/faiface/pixel/pixelgl"
-
-// Warning: technical stuff below.
-
-// VertexFormat is an internal format of the OpenGL vertex data.
-//
-// You can actually change this and all of the Pixel's functions will use the new format.
-// Only change when you're implementing an OpenGL effect or something similar.
-var VertexFormat = DefaultVertexFormat()
-
-// DefaultVertexFormat returns the default vertex format used by Pixel.
-func DefaultVertexFormat() pixelgl.VertexFormat {
- return pixelgl.VertexFormat{
- {Purpose: pixelgl.Position, Size: 2},
- {Purpose: pixelgl.Color, Size: 4},
- {Purpose: pixelgl.TexCoord, Size: 2},
- }
-}
-
-// ConvertVertexData converts data in the oldFormat to the newFormat. Vertex attributes in the new format
-// will be copied from the corresponding vertex attributes in the old format. If a vertex attribute in the new format
-// has no corresponding attribute in the old format, it will be filled with zeros.
-func ConvertVertexData(oldFormat, newFormat pixelgl.VertexFormat, data []float64) []float64 {
- // calculate the mapping between old and new format
- // if i is a start of a vertex attribute in the new format, then mapping[i] returns
- // the index where the same attribute starts in the old format
- mapping := make(map[int]int)
- i := 0
- for _, newAttr := range newFormat {
- j := 0
- for _, oldAttr := range oldFormat {
- if newAttr == oldAttr {
- mapping[i] = j
- break
- }
- j += oldAttr.Size
- }
- i += newAttr.Size
- }
-
- oldData, newData := data, []float64{}
-
- for i := 0; i < len(oldData); i += oldFormat.Size() {
- j := 0
- for _, attr := range newFormat {
- if oldIndex, ok := mapping[j]; ok { // the attribute was found in the old format
- newData = append(newData, oldData[i+oldIndex:i+oldIndex+attr.Size]...)
- } else { // the attribute wasn't found in the old format, so fill with zeros
- newData = append(newData, make([]float64, attr.Size)...)
- }
- j += attr.Size
- }
- }
-
- return newData
-}
diff --git a/pixelgl/interface.go b/pixelgl/interface.go
index 86ab87f333bac46e613962b394b77434f8fa4ae6..2b7fbd613dff93ee36cd924bd04e60ce5fb03e58 100644
--- a/pixelgl/interface.go
+++ b/pixelgl/interface.go
@@ -12,10 +12,10 @@ package pixelgl
// The recommended way to implement a Doer is to wrap another Doer (vertex array wraps texture and so on), let's call
// it parent. Then the Do method will look like this:
//
-// func (o *MyObject) Do(sub func()) {
-// o.parent.Do(func() {
+// func (o *MyObject) Do(sub func(Context)) {
+// o.parent.Do(func(ctx Context) {
// // enter the object's state
-// sub()
+// sub(ctx)
// // leave the object's state
// })
// }
@@ -23,6 +23,45 @@ package pixelgl
// It might seem difficult to grasp this kind of recursion at first, but it's really simple. What it's basically saying
// is: "Hey parent, enter your state, then let me enter mine, then I'll do whatever I'm supposed to do in the middle.
// After that I'll leave my state and please leave your state too parent."
+//
+// Also notice, that the functions are passing a Context around. This context contains the most important state variables.
+// Usually, you just pass it as you received it. If you want to pass a changed context to your child (e.g. your a shader),
+// use ctx.With* methods.
type Doer interface {
- Do(sub func())
+ Do(sub func(Context))
+}
+
+// Context takes state from one object to another. OpenGL is a state machine, so we have to approach it like that.
+// However, global variables are evil, so we have Context, that transfers important OpenGL state from one object to another.
+//
+// This type does *not* represent an OpenGL context in the OpenGL terminology.
+type Context struct {
+ vertexFormat VertexFormat
+ shader *Shader
+}
+
+// VertexFormat returns the current vertex format.
+func (c Context) VertexFormat() VertexFormat {
+ return c.vertexFormat
+}
+
+// Shader returns the current shader.
+func (c Context) Shader() *Shader {
+ return c.shader
+}
+
+// WithVertexFormat returns a copy of this context with the specified vertex format.
+func (c Context) WithVertexFormat(vf VertexFormat) Context {
+ return Context{
+ vertexFormat: vf,
+ shader: c.shader,
+ }
+}
+
+// WithShader returns a copy of this context with the specified shader.
+func (c Context) WithShader(s *Shader) Context {
+ return Context{
+ vertexFormat: c.vertexFormat,
+ shader: s,
+ }
}
diff --git a/pixelgl/shader.go b/pixelgl/shader.go
index 7c28f786b5292343b51c28283b3b90f646f234a6..134f4c46b3f7bf2aaf19cdc8432b53940411b694 100644
--- a/pixelgl/shader.go
+++ b/pixelgl/shader.go
@@ -22,7 +22,7 @@ func NewShader(parent Doer, vertexShader, fragmentShader string) (*Shader, error
}
var err, glerr error
- parent.Do(func() {
+ parent.Do(func(ctx Context) {
err, glerr = DoErrGLErr(func() error {
var vshader, fshader uint32
@@ -105,7 +105,7 @@ func NewShader(parent Doer, vertexShader, fragmentShader string) (*Shader, error
// Delete deletes a shader program. Don't use a shader after deletion.
func (s *Shader) Delete() {
- s.parent.Do(func() {
+ s.parent.Do(func(ctx Context) {
DoNoBlock(func() {
gl.DeleteProgram(s.program)
})
@@ -113,12 +113,12 @@ func (s *Shader) Delete() {
}
// Do stars using a shader, executes sub, and stops using it.
-func (s *Shader) Do(sub func()) {
- s.parent.Do(func() {
+func (s *Shader) Do(sub func(Context)) {
+ s.parent.Do(func(ctx Context) {
DoNoBlock(func() {
gl.UseProgram(s.program)
})
- sub()
+ sub(ctx.WithShader(s))
DoNoBlock(func() {
gl.UseProgram(0)
})
diff --git a/pixelgl/texture.go b/pixelgl/texture.go
index 29ff28e74128877d398ee6bc38389784d589d470..3f9f8c9020e6c725f82e9f0bbd952b906234b031 100644
--- a/pixelgl/texture.go
+++ b/pixelgl/texture.go
@@ -17,7 +17,7 @@ func NewTexture(parent Doer, width, height int, pixels []uint8) (*Texture, error
texture := &Texture{parent: parent}
var err error
- parent.Do(func() {
+ parent.Do(func(ctx Context) {
err = DoGLErr(func() {
gl.GenTextures(1, &texture.tex)
gl.BindTexture(gl.TEXTURE_2D, texture.tex)
@@ -48,7 +48,7 @@ func NewTexture(parent Doer, width, height int, pixels []uint8) (*Texture, error
// Delete deletes a texture. Don't use a texture after deletion.
func (t *Texture) Delete() {
- t.parent.Do(func() {
+ t.parent.Do(func(ctx Context) {
DoNoBlock(func() {
gl.DeleteTextures(1, &t.tex)
})
@@ -56,12 +56,12 @@ func (t *Texture) Delete() {
}
// Do bind a texture, executes sub, and unbinds the texture.
-func (t *Texture) Do(sub func()) {
- t.parent.Do(func() {
+func (t *Texture) Do(sub func(Context)) {
+ t.parent.Do(func(ctx Context) {
DoNoBlock(func() {
gl.BindTexture(gl.TEXTURE_2D, t.tex)
})
- sub()
+ sub(ctx)
DoNoBlock(func() {
gl.BindTexture(gl.TEXTURE_2D, 0)
})
diff --git a/pixelgl/vertex.go b/pixelgl/vertex.go
index a0ed2f434956698074a1ab1dfdc3d91962048cef..a9c842088db168487f6250083b282f2337e0b2c8 100644
--- a/pixelgl/vertex.go
+++ b/pixelgl/vertex.go
@@ -125,7 +125,7 @@ func NewVertexArray(parent Doer, format VertexFormat, mode VertexDrawMode, usage
}
var err error
- parent.Do(func() {
+ parent.Do(func(ctx Context) {
err = DoGLErr(func() {
gl.GenVertexArrays(1, &va.vao)
gl.BindVertexArray(va.vao)
@@ -161,7 +161,7 @@ func NewVertexArray(parent Doer, format VertexFormat, mode VertexDrawMode, usage
// Delete deletes a vertex array and it's associated vertex buffer. Don't use a vertex array after deletion.
func (va *VertexArray) Delete() {
- va.parent.Do(func() {
+ va.parent.Do(func(ctx Context) {
DoNoBlock(func() {
gl.DeleteVertexArrays(1, &va.vao)
gl.DeleteBuffers(1, &va.vbo)
@@ -193,7 +193,7 @@ func (va *VertexArray) DrawMode() VertexDrawMode {
// Draw draws a vertex array.
func (va *VertexArray) Draw() {
- va.Do(func() {})
+ va.Do(func(Context) {})
}
// Data returns a copy of data inside a vertex array (actually it's vertex buffer).
@@ -233,13 +233,13 @@ func (va *VertexArray) SetVertexAttribute(vertex int, attr VertexAttribute, data
}
// Do binds a vertex arrray and it's associated vertex buffer, executes sub, and unbinds the vertex array and it's vertex buffer.
-func (va *VertexArray) Do(sub func()) {
- va.parent.Do(func() {
+func (va *VertexArray) Do(sub func(Context)) {
+ va.parent.Do(func(ctx Context) {
DoNoBlock(func() {
gl.BindVertexArray(va.vao)
gl.BindBuffer(gl.ARRAY_BUFFER, va.vbo)
})
- sub()
+ sub(ctx)
DoNoBlock(func() {
gl.DrawArrays(uint32(va.mode), 0, int32(va.count))
gl.BindBuffer(gl.ARRAY_BUFFER, 0)
diff --git a/window.go b/window.go
index d06c9b23a87f7339254e604ff5168ae041a3ab93..6b5c85a3b355b27c188d77066326f3eca6c5f207 100644
--- a/window.go
+++ b/window.go
@@ -108,7 +108,7 @@ func NewWindow(config WindowConfig) (*Window, error) {
// Delete destroys a window. The window can't be used any further.
func (w *Window) Delete() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.Destroy()
})
@@ -117,14 +117,14 @@ func (w *Window) Delete() {
// Clear clears the window with a color.
func (w *Window) Clear(c color.Color) {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Clear(colorToRGBA(c))
})
}
// Update swaps buffers and polls events.
func (w *Window) Update() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
if w.config.VSync {
glfw.SwapInterval(1)
@@ -137,7 +137,7 @@ func (w *Window) Update() {
// SetTitle changes the title of a window.
func (w *Window) SetTitle(title string) {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.SetTitle(title)
})
@@ -147,7 +147,7 @@ func (w *Window) SetTitle(title string) {
// SetSize resizes a window to the specified size in pixels.
// In case of a fullscreen window, it changes the resolution of that window.
func (w *Window) SetSize(width, height float64) {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.SetSize(int(width), int(height))
})
@@ -156,7 +156,7 @@ func (w *Window) SetSize(width, height float64) {
// Size returns the size of the client area of a window (the part you can draw on).
func (w *Window) Size() (width, height float64) {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
wi, hi := w.window.GetSize()
width = float64(wi)
@@ -168,7 +168,7 @@ func (w *Window) Size() (width, height float64) {
// Show makes a window visible if it was hidden.
func (w *Window) Show() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.Show()
})
@@ -177,7 +177,7 @@ func (w *Window) Show() {
// Hide hides a window if it was visible.
func (w *Window) Hide() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.Hide()
})
@@ -191,7 +191,7 @@ func (w *Window) Hide() {
func (w *Window) SetFullscreen(monitor *Monitor) {
if w.Monitor() != monitor {
if monitor == nil {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.SetMonitor(
nil,
@@ -204,7 +204,7 @@ func (w *Window) SetFullscreen(monitor *Monitor) {
})
})
} else {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.restore.xpos, w.restore.ypos = w.window.GetPos()
w.restore.width, w.restore.height = w.window.GetSize()
@@ -233,7 +233,7 @@ func (w *Window) IsFullscreen() bool {
// Monitor returns a monitor a fullscreen window is on. If the window is not fullscreen, this function returns nil.
func (w *Window) Monitor() *Monitor {
var monitor *glfw.Monitor
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
monitor = pixelgl.DoVal(func() interface{} {
return w.window.GetMonitor()
}).(*glfw.Monitor)
@@ -248,7 +248,7 @@ func (w *Window) Monitor() *Monitor {
// Focus brings a window to the front and sets input focus.
func (w *Window) Focus() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.Focus()
})
@@ -258,7 +258,7 @@ func (w *Window) Focus() {
// Focused returns true if a window has input focus.
func (w *Window) Focused() bool {
var focused bool
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
focused = pixelgl.DoVal(func() interface{} {
return w.window.GetAttrib(glfw.Focused) == glfw.True
}).(bool)
@@ -268,7 +268,7 @@ func (w *Window) Focused() bool {
// Maximize puts a windowed window to a maximized state.
func (w *Window) Maximize() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.Maximize()
})
@@ -277,7 +277,7 @@ func (w *Window) Maximize() {
// Restore restores a windowed window from a maximized state.
func (w *Window) Restore() {
- w.Do(func() {
+ w.Do(func(pixelgl.Context) {
pixelgl.Do(func() {
w.window.Restore()
})
@@ -290,7 +290,7 @@ var currentWindow struct {
}
// Do makes the context of this window current, if it's not already, and executes sub.
-func (w *Window) Do(sub func()) {
+func (w *Window) Do(sub func(pixelgl.Context)) {
currentWindow.Lock()
defer currentWindow.Unlock()
@@ -302,5 +302,5 @@ func (w *Window) Do(sub func()) {
currentWindow.handler = w
}
- sub()
+ sub(pixelgl.Context{})
}