video

Documentation

Overview

Package video takes care on the game display. It also creates the window using GLFW. It exports the Refresh callback used by the libretro implementation.

Index

• func NewImage(file string) uint32
• func XYWHTo4points(x, y, w, h, fbh float32) (x1, y1, x2, y2, x3, y3, x4, y4 float32)
• type Color
• type Video
  • func Init(fullscreen bool) *Video
  • func (video *Video) Configure(fullscreen bool)
  • func (video *Video) DrawBorder(x, y, w, h, borderWidth float32, c Color)
  • func (video *Video) DrawCircle(x, y, r float32, c Color)
  • func (video *Video) DrawImage(image uint32, x, y, w, h float32, scale float32, c Color)
  • func (video *Video) DrawRect(x, y, w, h, r float32, c Color)
  • func (video *Video) Reconfigure(fullscreen bool)
  • func (video *Video) Refresh(data unsafe.Pointer, width int32, height int32, pitch int32)
  • func (video *Video) Render()
  • func (video *Video) ResetPitch()
  • func (video *Video) ResetRot()
  • func (video *Video) ResizeViewport()
  • func (video *Video) ScissorEnd()
  • func (video *Video) ScissorStart(x, y, w, h int32)
  • func (video *Video) SetPixelFormat(format uint32) bool
  • func (video *Video) SetRotation(rot uint) bool
  • func (video *Video) TakeScreenshot(name string) error
  • func (video *Video) UpdateFilter(filter string)
• type WindowInterface

Functions

func NewImage

func NewImage(file string) uint32

NewImage opens an image file, upload it the the GPU and returns the texture id

func XYWHTo4points

func XYWHTo4points(x, y, w, h, fbh float32) (x1, y1, x2, y2, x3, y3, x4, y4 float32)

XYWHTo4points converts coordinates from (x, y, width, height) to (x1, y1, x2, y2, x3, y3, x4, y4)

Types

type Color

type Color struct {
	R, G, B, A float32
}

Color is an RGBA type that we use in the menu

type Video

type Video struct {
	Window WindowInterface
	Geom   libretro.GameGeometry
	Font   *glfont.Font
	// contains filtered or unexported fields
}

Video holds the state of the video package

func Init

func Init(fullscreen bool) *Video

Init instanciates the video package

func (*Video) Configure

func (video *Video) Configure(fullscreen bool)

Configure instanciates the video package

func (*Video) DrawBorder

func (video *Video) DrawBorder(x, y, w, h, borderWidth float32, c Color)

DrawBorder draws a colored rectangle border

func (*Video) DrawCircle

func (video *Video) DrawCircle(x, y, r float32, c Color)

DrawCircle draws a circle

func (*Video) DrawImage

func (video *Video) DrawImage(image uint32, x, y, w, h float32, scale float32, c Color)

DrawImage draws an image with x, y, w, h

func (*Video) DrawRect

func (video *Video) DrawRect(x, y, w, h, r float32, c Color)

DrawRect draws a rectangle and supports rounded corners

func (*Video) Reconfigure

func (video *Video) Reconfigure(fullscreen bool)

Reconfigure destroys and recreates the window with new attributes

func (*Video) Refresh

func (video *Video) Refresh(data unsafe.Pointer, width int32, height int32, pitch int32)

Refresh the texture framebuffer

func (*Video) Render

func (video *Video) Render()

Render the current frame

func (*Video) ResetPitch

func (video *Video) ResetPitch()

ResetPitch should be called when unloading a game so that the next game won't be rendered with the wrong pitch

func (*Video) ResetRot

func (video *Video) ResetRot()

ResetRot should be called when unloading a game so that the next game won't be rendered with the wrong rotation

func (*Video) ResizeViewport

func (video *Video) ResizeViewport()

ResizeViewport resizes the GL viewport to the framebuffer size

func (*Video) ScissorEnd

func (video *Video) ScissorEnd()

ScissorEnd closes a GL scissor box

func (*Video) ScissorStart

func (video *Video) ScissorStart(x, y, w, h int32)

ScissorStart starts a GL scissor box, don't forget to call ScissorEnd

func (*Video) SetPixelFormat

func (video *Video) SetPixelFormat(format uint32) bool

SetPixelFormat is a callback passed to the libretro implementation. It allows the core or the game to tell us which pixel format should be used for the display.

func (*Video) SetRotation

func (video *Video) SetRotation(rot uint) bool

SetRotation rotates the game image as requested by the core

func (*Video) TakeScreenshot

func (video *Video) TakeScreenshot(name string) error

TakeScreenshot captures the ouput of video.Render and writes it to a file

func (*Video) UpdateFilter

func (video *Video) UpdateFilter(filter string)

UpdateFilter configures the game texture filter and shader. We currently support 4 modes: Raw: nearest Smooth: linear Pixel Perfect: sharp-bilinear CRT: zfast-crt

type WindowInterface

type WindowInterface interface {
	GetFramebufferSize() (width, height int)
	Destroy()
	MakeContextCurrent()
	SetSizeLimits(minw, minh, maxw, maxh int)
	SetInputMode(mode glfw.InputMode, value int)
	GetKey(key glfw.Key) glfw.Action
	SetShouldClose(bool)
	ShouldClose() bool
	SetTitle(string)
	SwapBuffers()
}

WindowInterface lists all the methods from glfw.Window that we are using. It is there only to allow mocking during tests.