// Draw actually renders the shape on the surface.
func (box *Box) Draw() {
box.program.Use()
gl.VertexAttribPointer(box.posId, 2, gl.FLOAT, false, 0, &box.vertices[0])
gl.EnableVertexAttribArray(box.posId)
gl.VertexAttribPointer(box.colorId, 4, gl.FLOAT, false, 0, &box.vColor[0])
gl.EnableVertexAttribArray(box.colorId)
gl.UniformMatrix4fv(int32(box.modelMatrixId), 1, false, (*float32)(&box.modelMatrix[0]))
gl.UniformMatrix4fv(int32(box.projMatrixId), 1, false, (*float32)(&box.projMatrix[0]))
gl.UniformMatrix4fv(int32(box.viewMatrixId), 1, false, (*float32)(&box.viewMatrix[0]))
gl.Uniform1f(int32(box.texRatioId), 0.0)
// Texture
if len(box.texCoords) > 0 {
gl.Uniform1f(int32(box.texRatioId), 1.0)
gl.VertexAttribPointer(box.texInId, 2, gl.FLOAT, false, 0, &box.texCoords[0])
gl.EnableVertexAttribArray(box.texInId)
gl.ActiveTexture(gl.TEXTURE0)
gl.BindTexture(gl.TEXTURE_2D, box.texBuffer)
gl.Uniform1i(int32(box.textureId), 0)
}
gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
gl.Flush()
gl.Finish()
}
func (renderState *renderState) init(window gorgasm.Window) {
window.MakeContextCurrent()
renderState.window = window
width, height := window.GetSize()
// Set the viewport
gl.Viewport(0, 0, gl.Sizei(width), gl.Sizei(height))
check()
// Compile the shaders
program := Program(FragmentShader(fsh), VertexShader(vsh))
gl.UseProgram(program)
check()
// Get attributes
attrPos = uint32(gl.GetAttribLocation(program, "pos"))
attrTexIn = uint32(gl.GetAttribLocation(program, "texIn"))
unifTexture = gl.GetUniformLocation(program, "texture")
gl.EnableVertexAttribArray(attrPos)
gl.EnableVertexAttribArray(attrTexIn)
check()
// Upload vertices data
gl.GenBuffers(1, &verticesArrayBuffer)
gl.BindBuffer(gl.ARRAY_BUFFER, verticesArrayBuffer)
gl.BufferData(gl.ARRAY_BUFFER, gl.SizeiPtr(len(vertices))*4, gl.Void(&vertices[0]), gl.STATIC_DRAW)
check()
// Upload texture data
img, err := loadImage(GOPHER_PNG)
if err != nil {
panic(err)
}
// Prepare the image to be placed on a texture.
bounds := img.Bounds()
imgWidth, imgHeight := bounds.Size().X, bounds.Size().Y
buffer := make([]byte, imgWidth*imgHeight*4)
index := 0
for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
for x := bounds.Min.X; x < bounds.Max.X; x++ {
r, g, b, a := img.At(x, y).RGBA()
buffer[index] = byte(r)
buffer[index+1] = byte(g)
buffer[index+2] = byte(b)
buffer[index+3] = byte(a)
index += 4
}
}
gl.GenTextures(1, &textureBuffer)
gl.BindTexture(gl.TEXTURE_2D, textureBuffer)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.Sizei(imgWidth), gl.Sizei(imgHeight), 0, gl.RGBA, gl.UNSIGNED_BYTE, gl.Void(&buffer[0]))
check()
gl.ClearColor(0.0, 0.0, 0.0, 1.0)
}
func (renderState *renderState) init(window mandala.Window) {
window.MakeContextCurrent()
renderState.window = window
width, height := window.GetSize()
// Set the viewport
gl.Viewport(0, 0, gl.Sizei(width), gl.Sizei(height))
check()
// Compile the shaders
program := shaders.NewProgram(fsh, vsh)
program.Use()
check()
// Get attributes
attrPos = program.GetAttribute("pos")
attrTexIn = program.GetAttribute("texIn")
unifTexture = program.GetUniform("texture")
gl.EnableVertexAttribArray(attrPos)
gl.EnableVertexAttribArray(attrTexIn)
check()
// Upload texture data
img, err := loadImage(GOPHER_PNG)
if err != nil {
panic(err)
}
// Prepare the image to be placed on a texture.
bounds := img.Bounds()
imgWidth, imgHeight := bounds.Size().X, bounds.Size().Y
buffer := make([]byte, imgWidth*imgHeight*4)
index := 0
for y := bounds.Min.Y; y < bounds.Max.Y; y++ {
for x := bounds.Min.X; x < bounds.Max.X; x++ {
r, g, b, a := img.At(x, y).RGBA()
buffer[index] = byte(r)
buffer[index+1] = byte(g)
buffer[index+2] = byte(b)
buffer[index+3] = byte(a)
index += 4
}
}
gl.GenTextures(1, &textureBuffer)
gl.BindTexture(gl.TEXTURE_2D, textureBuffer)
gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, gl.Sizei(imgWidth), gl.Sizei(imgHeight), 0, gl.RGBA, gl.UNSIGNED_BYTE, gl.Void(&buffer[0]))
check()
gl.ClearColor(0.0, 0.0, 0.0, 1.0)
}
// Draw actually renders the segment on the surface.
func (segment *Segment) Draw() {
segment.program.Use()
gl.VertexAttribPointer(segment.posId, 2, gl.FLOAT, false, 0, &segment.vertices[0])
gl.EnableVertexAttribArray(segment.posId)
gl.VertexAttribPointer(segment.colorId, 4, gl.FLOAT, false, 0, &segment.vColor[0])
gl.EnableVertexAttribArray(segment.colorId)
gl.UniformMatrix4fv(int32(segment.modelMatrixId), 1, false, (*float32)(&segment.modelMatrix[0]))
gl.UniformMatrix4fv(int32(segment.projMatrixId), 1, false, (*float32)(&segment.projMatrix[0]))
gl.UniformMatrix4fv(int32(segment.viewMatrixId), 1, false, (*float32)(&segment.viewMatrix[0]))
gl.DrawArrays(gl.LINES, 0, 2)
gl.Flush()
gl.Finish()
}
func NewCube() *Cube {
cube := new(Cube)
cube.model = mathgl.Ident4f()
cube.Vertices = NewBufferFloat([]float32{
// Front
1, -1, 1, 1, TEX_COORD_MAX, 0,
1, 1, 1, 1, TEX_COORD_MAX, TEX_COORD_MAX,
-1, 1, 1, 1, 0, TEX_COORD_MAX,
-1, -1, 1, 1, 0, 0,
// Back
1, 1, -1, 1, TEX_COORD_MAX, 0,
-1, -1, -1, 1, 0, TEX_COORD_MAX,
1, -1, -1, 1, TEX_COORD_MAX, TEX_COORD_MAX,
-1, 1, -1, 1, 0, 0,
// Left
-1, -1, 1, 1, TEX_COORD_MAX, 0,
-1, 1, 1, 1, TEX_COORD_MAX, TEX_COORD_MAX,
-1, 1, -1, 1, 0, TEX_COORD_MAX,
-1, -1, -1, 1, 0, 0,
// Right
1, -1, -1, 1, TEX_COORD_MAX, 0,
1, 1, -1, 1, TEX_COORD_MAX, TEX_COORD_MAX,
1, 1, 1, 1, 0, TEX_COORD_MAX,
1, -1, 1, 1, 0, 0,
// Top
1, 1, 1, 1, TEX_COORD_MAX, 0,
1, 1, -1, 1, TEX_COORD_MAX, TEX_COORD_MAX,
-1, 1, -1, 1, 0, TEX_COORD_MAX,
-1, 1, 1, 1, 0, 0,
// Bottom
1, -1, -1, 1, TEX_COORD_MAX, 0,
1, -1, 1, 1, TEX_COORD_MAX, TEX_COORD_MAX,
-1, -1, 1, 1, 0, TEX_COORD_MAX,
-1, -1, -1, 1, 0, 0,
})
cube.indices = NewBufferByte([]byte{
// Front
0, 1, 2,
2, 3, 0,
// Back
4, 5, 6,
4, 5, 7,
// Left
8, 9, 10,
10, 11, 8,
// Right
12, 13, 14,
14, 15, 12,
// Top
16, 17, 18,
18, 19, 16,
// Bottom
20, 21, 22,
22, 23, 20,
})
fragmentShader := (FragmentShader)(`
precision highp float;
varying vec2 texOut;
uniform sampler2D texture;
void main() {
gl_FragColor = texture2D(texture, texOut);
}
`)
vertexShader := (VertexShader)(`
uniform mat4 model;
uniform mat4 projection_view;
attribute vec4 pos;
attribute vec2 texIn;
varying vec2 texOut;
void main() {
gl_Position = projection_view*model*pos;
texOut = texIn;
}
`)
fsh := fragmentShader.Compile()
vsh := vertexShader.Compile()
cube.Program.Link(fsh, vsh)
cube.Program.Use()
cube.attrPos = cube.Program.GetAttribute("pos")
cube.attrColor = cube.Program.GetAttribute("color")
cube.attrTexIn = cube.Program.GetAttribute("texIn")
cube.uniformTexture = cube.Program.GetUniform("texture")
cube.uniformModel = cube.Program.GetUniform("model")
cube.uniformProjectionView = cube.Program.GetUniform("projection_view")
gl.EnableVertexAttribArray(cube.attrPos)
gl.EnableVertexAttribArray(cube.attrColor)
gl.EnableVertexAttribArray(cube.attrTexIn)
return cube
}
