sucre

README

sucre

An easy to use library made for 2D drawing using OpenGL 3.2

Installation

go get github.com/atrika/sucre

Documentation

https://godoc.org/github.com/atrika/sucre

Requirements

The textures used must be squares, and they must all have the same sizes. For example:

   /home/username/Images/textures
      texture1.png (512x512)
      texture2.png (512x512)

Example using glfw

package main

import "github.com/atrika/sucre"
import "github.com/go-gl/glfw/v3.1/glfw"
import "github.com/go-gl/gl/v3.2-core/gl"
import "runtime"
import "math"

func init() {
   runtime.LockOSThread()
}

func main() {

   err := glfw.Init()
   if err != nil {
      panic(err)
   }
   defer glfw.Terminate()
   
   
   glfw.WindowHint(glfw.ContextVersionMajor, 3)
   glfw.WindowHint(glfw.ContextVersionMinor, 2)
   glfw.WindowHint(glfw.OpenGLProfile, glfw.OpenGLCoreProfile)
   
   window, err := glfw.CreateWindow(800, 800, "Testing", nil, nil)
   if err != nil {
      panic(err)
   }
   
   window.MakeContextCurrent()
   
   if err := gl.Init(); err != nil {
      panic(err)
   }

   var context sucre.Context   
   context.Initialize("/home/username/Images/textures/512")
   context.SetCameraPosition(0.0, 0.0)
   context.SetCameraAngle(0.0)
   context.SetCameraSize(10.0, 10.0)
   context.SetClearColor(sucre.Color{0.4, 0.1, 0.1})
      
   tex7, _  := context.GetTextureId("7.png")
   tex5, _  := context.GetTextureId("5.png")
   
   for !window.ShouldClose() {
      context.ClearScene()
      
      basic := sucre.BasicRectData{
         Width:  3.0,
         Height: 3.0,
         Angle:  0.0,
         PosX:   3.0,
         PosY:   3.0,
         Depth:  0.5,
      }      
      rect := sucre.RectData{basic, tex7}
      
      // Square of size 3 at (3,3) using 7.png
      context.AddRect(rect)
      
      rect.PosX    = -3.0
      rect.PosY    = -3.0
      rect.Height  =  2.0
      rect.Angle   = float32(math.Pi / 6.0)
      rect.Texture = tex5
      
      // Rotated 3x2 rectangle at (-3, -3) using 5.png
      context.AddRect(rect)
      
      rect.Width   = 1.0
      rect.Height  = 1.0
      rect.Depth   = 0.6 
      rect.Texture = tex7
      
      // Rotated square of size 1 at (-3, -3), behind the
      //  3x2 rectangle and using 7.png
      context.AddRect(rect)
      
      context.Draw()
      
      window.SwapBuffers()
      glfw.PollEvents()
   }
}

Documentation

Index

• type BasicRectData
• type Color
• type Context
  • func (this *Context) AddRect(data RectData)
  • func (this *Context) ClearScene()
  • func (this *Context) Draw()
  • func (this *Context) GetTextureId(name string) (Texture, bool)
  • func (this *Context) Initialize(textureLocation string)
  • func (this *Context) SetCameraAngle(rad float64)
  • func (this *Context) SetCameraPosition(posX, posY float32)
  • func (this *Context) SetCameraSize(width, height float32)
  • func (this *Context) SetClearColor(bg Color)
• type RectData
• type Texture

Types

type BasicRectData

type BasicRectData struct {
	PosX, PosY    float32
	Width, Height float32
	Angle         float32 // in radians
	Depth         float32 // 0.0 <= Depth < 1.0
}

type Color

type Color struct {
	R, G, B float32
}

type Context

type Context struct {
	// contains filtered or unexported fields
}

func (*Context) AddRect

func (this *Context) AddRect(data RectData)

Adds a Rect to be drawn in the next Draw call

func (*Context) ClearScene

func (this *Context) ClearScene()

Clears the scene of all Rects

func (*Context) Draw

func (this *Context) Draw()

Draws the Rects

func (*Context) GetTextureId

func (this *Context) GetTextureId(name string) (Texture, bool)

Gets the ID of a texture

func (*Context) Initialize

func (this *Context) Initialize(textureLocation string)

Initializes OpenGL and loads the textures from disk

func (*Context) SetCameraAngle

func (this *Context) SetCameraAngle(rad float64)

Sets the angle of the camera in radians (default is 0)

func (*Context) SetCameraPosition

func (this *Context) SetCameraPosition(posX, posY float32)

Sets the position of the camera (default is [0;0])

func (*Context) SetCameraSize

func (this *Context) SetCameraSize(width, height float32)

Sets the size of the camera (default 1.0 for w and h)

func (*Context) SetClearColor

func (this *Context) SetClearColor(bg Color)

Sets the color used to clear the screen (default is black)

type RectData

type RectData struct {
	BasicRectData
	Texture
}

type Texture

type Texture struct {
	Id          uint32
	Transparent bool
}