add opengl2 sdl2 imgui implementation
This commit is contained in:
parent
0089093c7f
commit
7a8338c19d
309
platform/imgui_sdl2_gl2.go
Normal file
309
platform/imgui_sdl2_gl2.go
Normal file
@ -0,0 +1,309 @@
|
||||
package platform
|
||||
|
||||
import (
|
||||
"unsafe"
|
||||
|
||||
"github.com/FooSoft/imgui-go"
|
||||
"github.com/go-gl/gl/v2.1/gl"
|
||||
"github.com/veandco/go-sdl2/sdl"
|
||||
)
|
||||
|
||||
type imguiSdl2Gl2 struct {
|
||||
renderer *rendererGl2
|
||||
platform *platformSdl2
|
||||
}
|
||||
|
||||
func newImguiSdl2Gl2(window *sdl.Window) *imguiSdl2Gl2 {
|
||||
return &imguiSdl2Gl2{
|
||||
renderer: newRendererGl2(window),
|
||||
platform: newPlatformSdl2(window),
|
||||
}
|
||||
}
|
||||
|
||||
func (impl *imguiSdl2Gl2) NewFrame() {
|
||||
impl.platform.newFrame()
|
||||
impl.renderer.newFrame()
|
||||
}
|
||||
|
||||
func (impl *imguiSdl2Gl2) Render(drawData imgui.DrawData) {
|
||||
impl.renderer.render(drawData)
|
||||
}
|
||||
|
||||
func (impl *imguiSdl2Gl2) ProcessEvent(event sdl.Event) bool {
|
||||
return impl.platform.processEvent(event)
|
||||
}
|
||||
|
||||
func (impl *imguiSdl2Gl2) Shutdown() {
|
||||
impl.renderer.shutdown()
|
||||
}
|
||||
|
||||
type platformSdl2 struct {
|
||||
window *sdl.Window
|
||||
time uint64
|
||||
buttonsDown [3]bool
|
||||
}
|
||||
|
||||
func newPlatformSdl2(window *sdl.Window) *platformSdl2 {
|
||||
keys := map[int]int{
|
||||
imgui.KeyTab: sdl.SCANCODE_TAB,
|
||||
imgui.KeyLeftArrow: sdl.SCANCODE_LEFT,
|
||||
imgui.KeyRightArrow: sdl.SCANCODE_RIGHT,
|
||||
imgui.KeyUpArrow: sdl.SCANCODE_UP,
|
||||
imgui.KeyDownArrow: sdl.SCANCODE_DOWN,
|
||||
imgui.KeyPageUp: sdl.SCANCODE_PAGEUP,
|
||||
imgui.KeyPageDown: sdl.SCANCODE_PAGEDOWN,
|
||||
imgui.KeyHome: sdl.SCANCODE_HOME,
|
||||
imgui.KeyEnd: sdl.SCANCODE_END,
|
||||
imgui.KeyInsert: sdl.SCANCODE_INSERT,
|
||||
imgui.KeyDelete: sdl.SCANCODE_DELETE,
|
||||
imgui.KeyBackspace: sdl.SCANCODE_BACKSPACE,
|
||||
imgui.KeySpace: sdl.SCANCODE_BACKSPACE,
|
||||
imgui.KeyEnter: sdl.SCANCODE_RETURN,
|
||||
imgui.KeyEscape: sdl.SCANCODE_ESCAPE,
|
||||
imgui.KeyA: sdl.SCANCODE_A,
|
||||
imgui.KeyC: sdl.SCANCODE_C,
|
||||
imgui.KeyV: sdl.SCANCODE_V,
|
||||
imgui.KeyX: sdl.SCANCODE_X,
|
||||
imgui.KeyY: sdl.SCANCODE_Y,
|
||||
imgui.KeyZ: sdl.SCANCODE_Z,
|
||||
}
|
||||
|
||||
// Keyboard mapping. ImGui will use those indices to peek into the io.KeysDown[] array.
|
||||
io := imgui.CurrentIO()
|
||||
for imguiKey, nativeKey := range keys {
|
||||
io.KeyMap(imguiKey, nativeKey)
|
||||
}
|
||||
|
||||
return &platformSdl2{window: window}
|
||||
}
|
||||
|
||||
func (plat *platformSdl2) newFrame() {
|
||||
io := imgui.CurrentIO()
|
||||
|
||||
// Setup display size (every frame to accommodate for window resizing)
|
||||
windowWidth, windowHeight := plat.window.GetSize()
|
||||
io.SetDisplaySize(imgui.Vec2{X: float32(windowWidth), Y: float32(windowHeight)})
|
||||
|
||||
// Setup time step (we don't use SDL_GetTicks() because it is using millisecond resolution)
|
||||
frequency := sdl.GetPerformanceFrequency()
|
||||
currentTime := sdl.GetPerformanceCounter()
|
||||
if plat.time > 0 {
|
||||
io.SetDeltaTime(float32(currentTime-plat.time) / float32(frequency))
|
||||
} else {
|
||||
io.SetDeltaTime(1.0 / 60.0)
|
||||
}
|
||||
plat.time = currentTime
|
||||
|
||||
// If a mouse press event came, always pass it as "mouse held this frame", so we don't miss click-release events that are shorter than 1 frame.
|
||||
x, y, state := sdl.GetMouseState()
|
||||
for i, button := range []uint32{sdl.BUTTON_LEFT, sdl.BUTTON_RIGHT, sdl.BUTTON_MIDDLE} {
|
||||
io.SetMouseButtonDown(i, plat.buttonsDown[i] || (state&sdl.Button(button)) != 0)
|
||||
plat.buttonsDown[i] = false
|
||||
}
|
||||
|
||||
io.SetMousePosition(imgui.Vec2{X: float32(x), Y: float32(y)})
|
||||
}
|
||||
|
||||
// You can read the io.WantCaptureMouse, io.WantCaptureKeyboard flags to tell if dear imgui wants to use your inputs.
|
||||
// - When io.WantCaptureMouse is true, do not dispatch mouse input data to your main application.
|
||||
// - When io.WantCaptureKeyboard is true, do not dispatch keyboard input data to your main application.
|
||||
// Generally you may always pass all inputs to dear imgui, and hide them from your application based on those two flags.
|
||||
// If you have multiple SDL events and some of them are not meant to be used by dear imgui, you may need to filter events based on their windowID field.
|
||||
func (plat *platformSdl2) processEvent(event sdl.Event) bool {
|
||||
switch io := imgui.CurrentIO(); event.GetType() {
|
||||
case sdl.MOUSEWHEEL:
|
||||
wheelEvent := event.(*sdl.MouseWheelEvent)
|
||||
var deltaX, deltaY float32
|
||||
if wheelEvent.X > 0 {
|
||||
deltaX++
|
||||
} else if wheelEvent.X < 0 {
|
||||
deltaX--
|
||||
}
|
||||
if wheelEvent.Y > 0 {
|
||||
deltaY++
|
||||
} else if wheelEvent.Y < 0 {
|
||||
deltaY--
|
||||
}
|
||||
return true
|
||||
case sdl.MOUSEBUTTONDOWN:
|
||||
buttonEvent := event.(*sdl.MouseButtonEvent)
|
||||
switch buttonEvent.Button {
|
||||
case sdl.BUTTON_LEFT:
|
||||
plat.buttonsDown[0] = true
|
||||
break
|
||||
case sdl.BUTTON_RIGHT:
|
||||
plat.buttonsDown[1] = true
|
||||
break
|
||||
case sdl.BUTTON_MIDDLE:
|
||||
plat.buttonsDown[2] = true
|
||||
break
|
||||
}
|
||||
return true
|
||||
case sdl.TEXTINPUT:
|
||||
inputEvent := event.(*sdl.TextInputEvent)
|
||||
io.AddInputCharacters(string(inputEvent.Text[:]))
|
||||
return true
|
||||
case sdl.KEYDOWN:
|
||||
keyEvent := event.(*sdl.KeyboardEvent)
|
||||
io.KeyPress(int(keyEvent.Keysym.Scancode))
|
||||
modState := int(sdl.GetModState())
|
||||
io.KeyShift(modState&sdl.KMOD_LSHIFT, modState&sdl.KMOD_RSHIFT)
|
||||
io.KeyCtrl(modState&sdl.KMOD_LCTRL, modState&sdl.KMOD_RCTRL)
|
||||
io.KeyAlt(modState&sdl.KMOD_LALT, modState&sdl.KMOD_RALT)
|
||||
case sdl.KEYUP:
|
||||
keyEvent := event.(*sdl.KeyboardEvent)
|
||||
io.KeyRelease(int(keyEvent.Keysym.Scancode))
|
||||
modState := int(sdl.GetModState())
|
||||
io.KeyShift(modState&sdl.KMOD_LSHIFT, modState&sdl.KMOD_RSHIFT)
|
||||
io.KeyCtrl(modState&sdl.KMOD_LCTRL, modState&sdl.KMOD_RCTRL)
|
||||
io.KeyAlt(modState&sdl.KMOD_LALT, modState&sdl.KMOD_RALT)
|
||||
return true
|
||||
}
|
||||
|
||||
return false
|
||||
}
|
||||
|
||||
type rendererGl2 struct {
|
||||
window *sdl.Window
|
||||
context *sdl.GLContext
|
||||
fontTexture uint32
|
||||
}
|
||||
|
||||
func newRendererGl2(window *sdl.Window) *rendererGl2 {
|
||||
return &rendererGl2{window: window}
|
||||
}
|
||||
|
||||
func (rend *rendererGl2) newFrame() {
|
||||
if rend.fontTexture == 0 {
|
||||
rend.createFontsTexture()
|
||||
}
|
||||
|
||||
imgui.NewFrame()
|
||||
}
|
||||
|
||||
// OpenGL2 Render function.
|
||||
// Note that this implementation is little overcomplicated because we are saving/setting up/restoring every OpenGL state explicitly, in order to be able to run within any OpenGL engine that doesn't do so.
|
||||
func (rend *rendererGl2) render(drawData imgui.DrawData) {
|
||||
displayWidth, displayHeight := rend.window.GetSize()
|
||||
fbWidth, fbHeight := rend.window.GLGetDrawableSize()
|
||||
drawData.ScaleClipRects(imgui.Vec2{X: float32(fbWidth) / float32(displayWidth), Y: float32(fbHeight) / float32(displayHeight)})
|
||||
|
||||
// We are using the OpenGL fixed pipeline to make the example code simpler to read!
|
||||
// Setup render state: alpha-blending enabled, no face culling, no depth testing, scissor enabled, vertex/texcoord/color pointers, polygon fill.
|
||||
var lastTexture int32
|
||||
gl.GetIntegerv(gl.TEXTURE_BINDING_2D, &lastTexture)
|
||||
var lastPolygonMode [2]int32
|
||||
gl.GetIntegerv(gl.POLYGON_MODE, &lastPolygonMode[0])
|
||||
var lastViewport [4]int32
|
||||
gl.GetIntegerv(gl.VIEWPORT, &lastViewport[0])
|
||||
var lastScissorBox [4]int32
|
||||
gl.GetIntegerv(gl.SCISSOR_BOX, &lastScissorBox[0])
|
||||
gl.PushAttrib(gl.ENABLE_BIT | gl.COLOR_BUFFER_BIT | gl.TRANSFORM_BIT)
|
||||
gl.Enable(gl.BLEND)
|
||||
gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
|
||||
gl.Disable(gl.CULL_FACE)
|
||||
gl.Disable(gl.DEPTH_TEST)
|
||||
gl.Disable(gl.LIGHTING)
|
||||
gl.Disable(gl.COLOR_MATERIAL)
|
||||
gl.Enable(gl.SCISSOR_TEST)
|
||||
gl.EnableClientState(gl.VERTEX_ARRAY)
|
||||
gl.EnableClientState(gl.TEXTURE_COORD_ARRAY)
|
||||
gl.EnableClientState(gl.COLOR_ARRAY)
|
||||
gl.Enable(gl.TEXTURE_2D)
|
||||
gl.PolygonMode(gl.FRONT_AND_BACK, gl.FILL)
|
||||
|
||||
// You may want this if using this code in an OpenGL 3+ context where shaders may be bound
|
||||
// gl.UseProgram(0)
|
||||
|
||||
// Setup viewport, orthographic projection matrix
|
||||
// Our visible imgui space lies from draw_data->DisplayPos (top left) to draw_data->DisplayPos+data_data->DisplaySize (bottom right). DisplayMin is typically (0,0) for single viewport apps.
|
||||
gl.Viewport(0, 0, int32(fbWidth), int32(fbHeight))
|
||||
gl.MatrixMode(gl.PROJECTION)
|
||||
gl.PushMatrix()
|
||||
gl.LoadIdentity()
|
||||
gl.Ortho(0, float64(displayWidth), float64(displayHeight), 0, -1, 1)
|
||||
gl.MatrixMode(gl.MODELVIEW)
|
||||
gl.PushMatrix()
|
||||
gl.LoadIdentity()
|
||||
|
||||
vertexSize, vertexOffsetPos, vertexOffsetUv, vertexOffsetCol := imgui.VertexBufferLayout()
|
||||
indexSize := imgui.IndexBufferLayout()
|
||||
|
||||
drawType := gl.UNSIGNED_SHORT
|
||||
if indexSize == 4 {
|
||||
drawType = gl.UNSIGNED_INT
|
||||
}
|
||||
|
||||
// Render command lists
|
||||
for _, commandList := range drawData.CommandLists() {
|
||||
vertexBuffer, _ := commandList.VertexBuffer()
|
||||
indexBuffer, _ := commandList.IndexBuffer()
|
||||
indexBufferOffset := uintptr(indexBuffer)
|
||||
|
||||
gl.VertexPointer(2, gl.FLOAT, int32(vertexSize), unsafe.Pointer(uintptr(vertexBuffer)+uintptr(vertexOffsetPos)))
|
||||
gl.TexCoordPointer(2, gl.FLOAT, int32(vertexSize), unsafe.Pointer(uintptr(vertexBuffer)+uintptr(vertexOffsetUv)))
|
||||
gl.ColorPointer(4, gl.UNSIGNED_BYTE, int32(vertexSize), unsafe.Pointer(uintptr(vertexBuffer)+uintptr(vertexOffsetCol)))
|
||||
|
||||
for _, command := range commandList.Commands() {
|
||||
if command.HasUserCallback() {
|
||||
command.CallUserCallback(commandList)
|
||||
} else {
|
||||
clipRect := command.ClipRect()
|
||||
gl.Scissor(int32(clipRect.X), int32(fbHeight)-int32(clipRect.W), int32(clipRect.Z-clipRect.X), int32(clipRect.W-clipRect.Y))
|
||||
gl.BindTexture(gl.TEXTURE_2D, uint32(command.TextureID()))
|
||||
gl.DrawElements(gl.TRIANGLES, int32(command.ElementCount()), uint32(drawType), unsafe.Pointer(indexBufferOffset))
|
||||
}
|
||||
|
||||
indexBufferOffset += uintptr(command.ElementCount() * indexSize)
|
||||
}
|
||||
}
|
||||
|
||||
// Restore modified state
|
||||
gl.DisableClientState(gl.COLOR_ARRAY)
|
||||
gl.DisableClientState(gl.TEXTURE_COORD_ARRAY)
|
||||
gl.DisableClientState(gl.VERTEX_ARRAY)
|
||||
gl.BindTexture(gl.TEXTURE_2D, uint32(lastTexture))
|
||||
gl.MatrixMode(gl.MODELVIEW)
|
||||
gl.PopMatrix()
|
||||
gl.MatrixMode(gl.PROJECTION)
|
||||
gl.PopMatrix()
|
||||
gl.PopAttrib()
|
||||
gl.PolygonMode(gl.FRONT, uint32(lastPolygonMode[0]))
|
||||
gl.PolygonMode(gl.BACK, uint32(lastPolygonMode[1]))
|
||||
gl.Viewport(lastViewport[0], lastViewport[1], lastViewport[2], lastViewport[3])
|
||||
gl.Scissor(lastScissorBox[0], lastScissorBox[1], lastScissorBox[2], lastScissorBox[3])
|
||||
}
|
||||
|
||||
func (rend *rendererGl2) shutdown() {
|
||||
rend.destroyFontsTexture()
|
||||
}
|
||||
|
||||
func (rend *rendererGl2) createFontsTexture() {
|
||||
// Build texture atlas
|
||||
io := imgui.CurrentIO()
|
||||
image := io.Fonts().TextureDataRGBA32()
|
||||
|
||||
// Upload texture to graphics system
|
||||
var lastTexture int32
|
||||
gl.GetIntegerv(gl.TEXTURE_BINDING_2D, &lastTexture)
|
||||
gl.GenTextures(1, &rend.fontTexture)
|
||||
gl.BindTexture(gl.TEXTURE_2D, rend.fontTexture)
|
||||
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
|
||||
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
|
||||
gl.PixelStorei(gl.UNPACK_ROW_LENGTH, 0)
|
||||
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, int32(image.Width), int32(image.Height), 0, gl.RGBA, gl.UNSIGNED_BYTE, image.Pixels)
|
||||
|
||||
// Store our identifier
|
||||
io.Fonts().SetTextureID(imgui.TextureID(rend.fontTexture))
|
||||
|
||||
// Restore state
|
||||
gl.BindTexture(gl.TEXTURE_2D, uint32(lastTexture))
|
||||
}
|
||||
|
||||
func (rend *rendererGl2) destroyFontsTexture() {
|
||||
if rend.fontTexture != 0 {
|
||||
gl.DeleteTextures(1, &rend.fontTexture)
|
||||
imgui.CurrentIO().Fonts().SetTextureID(0)
|
||||
rend.fontTexture = 0
|
||||
}
|
||||
}
|
||||
@ -2,6 +2,8 @@ package platform
|
||||
|
||||
import (
|
||||
"errors"
|
||||
"runtime"
|
||||
"time"
|
||||
|
||||
"github.com/FooSoft/imgui-go"
|
||||
"github.com/go-gl/gl/v2.1/gl"
|
||||
@ -19,6 +21,8 @@ func Init() error {
|
||||
return errors.New("platform is already initialized")
|
||||
}
|
||||
|
||||
runtime.LockOSThread()
|
||||
|
||||
if err := sdl.Init(sdl.INIT_VIDEO); err != nil {
|
||||
return err
|
||||
}
|
||||
@ -31,9 +35,27 @@ func Init() error {
|
||||
return nil
|
||||
}
|
||||
|
||||
func ProcessEvents() error {
|
||||
var terminate bool
|
||||
|
||||
for !terminate {
|
||||
for event := sdl.PollEvent(); event != nil; event = sdl.PollEvent() {
|
||||
switch event.(type) {
|
||||
case *sdl.QuitEvent:
|
||||
terminate = true
|
||||
break
|
||||
}
|
||||
}
|
||||
|
||||
<-time.After(time.Millisecond * 25)
|
||||
}
|
||||
|
||||
return nil
|
||||
}
|
||||
|
||||
func Shutdown() error {
|
||||
if !platformIsInit {
|
||||
return errors.New("platform is not yet initialized")
|
||||
return errors.New("platform was not initialized")
|
||||
}
|
||||
|
||||
for _, w := range platformWindows {
|
||||
|
||||
Loading…
Reference in New Issue
Block a user