Golang gl.BindTexture函数代码示例

func (r *EffectsRenderer) initFramebuffer(w, h int) (fb uint32, tex uint32, err error) {
	gl.GenFramebuffers(1, &fb)
	gl.BindFramebuffer(gl.FRAMEBUFFER, fb)

	gl.GenTextures(1, &tex)
	gl.BindTexture(gl.TEXTURE_2D, tex)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, int32(w), int32(h), 0, gl.RGBA, gl.UNSIGNED_BYTE, nil)

	gl.FramebufferTexture2D(gl.DRAW_FRAMEBUFFER, gl.COLOR_ATTACHMENT0, gl.TEXTURE_2D, tex, 0)
	if err = r.GetError(); err != nil {
		return
	}
	buffers := []uint32{gl.COLOR_ATTACHMENT0}
	gl.DrawBuffers(1, &buffers[0])

	var rb uint32
	gl.GenRenderbuffers(1, &rb)
	gl.BindRenderbuffer(gl.RENDERBUFFER, rb)
	gl.RenderbufferStorage(gl.RENDERBUFFER, gl.STENCIL_INDEX8, int32(w), int32(h))
	gl.FramebufferRenderbuffer(gl.FRAMEBUFFER, gl.STENCIL_ATTACHMENT, gl.RENDERBUFFER, rb)

	gl.BindTexture(gl.TEXTURE_2D, 0)
	gl.BindFramebuffer(gl.FRAMEBUFFER, 0)
	gl.BindRenderbuffer(gl.RENDERBUFFER, 0)
	return
}

func (r *GlowRenderer) Draw() (err error) {
	gl.UseProgram(r.shader)
	gl.Uniform1i(r.textureUnitLoc, 0)
	gl.BindBuffer(gl.ARRAY_BUFFER, r.coords)
	gl.EnableVertexAttribArray(r.positionLoc)
	gl.VertexAttribPointer(r.positionLoc, 3, gl.FLOAT, false, 5*4, gl.PtrOffset(0))
	gl.EnableVertexAttribArray(r.textureLoc)
	gl.VertexAttribPointer(r.textureLoc, 2, gl.FLOAT, false, 5*4, gl.PtrOffset(3*4))
	gl.Uniform1i(r.blurAmountLoc, int32(r.blur))
	gl.Uniform1f(r.blurScaleLoc, r.scale)
	gl.Uniform1f(r.blurStrengthLoc, r.strength)
	gl.Uniform2f(r.bufferDimensionsLoc, float32(r.width), float32(r.height))

	gl.BindFramebuffer(gl.FRAMEBUFFER, r.BlurFb)
	gl.Viewport(0, 0, int32(r.width), int32(r.height))
	gl.ActiveTexture(gl.TEXTURE0)
	gl.BindTexture(gl.TEXTURE_2D, r.GlowTex)
	gl.Uniform1i(r.orientationLoc, 0)
	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
	gl.BindFramebuffer(gl.FRAMEBUFFER, 0)

	gl.Viewport(0, 0, int32(r.oldwidth), int32(r.oldheight))
	gl.BlendFunc(gl.ONE, gl.ONE)
	gl.BindTexture(gl.TEXTURE_2D, r.BlurTex)
	gl.Uniform1i(r.orientationLoc, 1)
	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)

	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	return nil
}

func getGLTexture(img image.Image, smoothing TextureSmoothing) (t uint32, err error) {
	var (
		data   *bytes.Buffer
		bounds image.Rectangle
		width  int
		height int
	)
	if data, err = imageBytes(img); err != nil {
		return
	}
	bounds = img.Bounds()
	width = bounds.Max.X - bounds.Min.X
	height = bounds.Max.Y - bounds.Min.Y
	gl.GenTextures(1, &t)
	gl.BindTexture(gl.TEXTURE_2D, t)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, int32(smoothing))
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, int32(smoothing))
	gl.TexImage2D(
		gl.TEXTURE_2D,
		0,
		gl.RGBA,
		int32(width),
		int32(height),
		0,
		gl.RGBA,
		gl.UNSIGNED_INT_8_8_8_8,
		gl.Ptr(data.Bytes()),
	)
	gl.GenerateMipmap(gl.TEXTURE_2D)
	gl.BindTexture(gl.TEXTURE_2D, 0)
	return
}

func LoadText(f *Font) (t *Text) {
	t = new(Text)
	t.font = f

	// text hover values
	// "resting state" of a text object is the min scale
	t.ScaleMin = 1.0
	t.ScaleMax = 1.1
	t.SetScale(1)

	// size of glfloat
	glfloat_size := int32(4)

	// stride of the buffered data
	xy_count := int32(2)
	stride := xy_count + int32(2)

	gl.GenVertexArrays(1, &t.vao)
	gl.GenBuffers(1, &t.vbo)
	gl.GenBuffers(1, &t.ebo)

	// vao
	gl.BindVertexArray(t.vao)

	gl.ActiveTexture(gl.TEXTURE0)
	gl.BindTexture(gl.TEXTURE_2D, t.font.textureID)

	// vbo
	// specify the buffer for which the VertexAttribPointer calls apply
	gl.BindBuffer(gl.ARRAY_BUFFER, t.vbo)

	gl.EnableVertexAttribArray(t.font.centeredPosition)
	gl.VertexAttribPointer(
		t.font.centeredPosition,
		2,
		gl.FLOAT,
		false,
		glfloat_size*stride,
		gl.PtrOffset(0),
	)

	gl.EnableVertexAttribArray(t.font.uv)
	gl.VertexAttribPointer(
		t.font.uv,
		2,
		gl.FLOAT,
		false,
		glfloat_size*stride,
		gl.PtrOffset(int(glfloat_size*xy_count)),
	)

	// ebo
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, t.ebo)

	// i am guessing that order is important here
	gl.BindVertexArray(0)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, 0)
	return t
}

func (t *Text) Draw() {
	if t.IsDebug {
		t.BoundingBox.Draw()
	}
	gl.UseProgram(t.font.program)

	gl.ActiveTexture(gl.TEXTURE0)
	gl.BindTexture(gl.TEXTURE_2D, t.font.textureID)

	// uniforms
	gl.Uniform1i(t.font.fragmentTextureUniform, 0)
	gl.Uniform4fv(t.font.colorUniform, 1, &t.color[0])
	gl.Uniform2fv(t.font.finalPositionUniform, 1, &t.finalPosition[0])
	gl.UniformMatrix4fv(t.font.orthographicMatrixUniform, 1, false, &t.font.OrthographicMatrix[0])
	gl.UniformMatrix4fv(t.font.scaleMatrixUniform, 1, false, &t.scaleMatrix[0])

	// draw
	drawCount := int32(t.RuneCount * 6)
	if drawCount > int32(t.eboIndexCount) {
		drawCount = int32(t.eboIndexCount)
	}
	if drawCount < 0 {
		drawCount = 0
	}
	gl.Enable(gl.BLEND)
	gl.BlendFunc(gl.SRC_ALPHA, gl.ONE_MINUS_SRC_ALPHA)
	gl.BindVertexArray(t.vao)
	gl.DrawElements(gl.TRIANGLES, drawCount, gl.UNSIGNED_INT, nil)
	gl.BindVertexArray(0)
	gl.Disable(gl.BLEND)
}

func newTexture(file string, texNum uint32) (uint32, error) {
	imgFile, err := os.Open(file)
	if err != nil {
		return 0, err
	}
	img, _, err := image.Decode(imgFile)

	rgba := image.NewRGBA(img.Bounds())
	if rgba.Stride != rgba.Rect.Size().X*4 {
		return 0, fmt.Errorf("unsupported stride")
	}
	draw.Draw(rgba, rgba.Bounds(), img, image.ZP, draw.Src)

	var texture uint32
	gl.GenTextures(1, &texture)
	gl.ActiveTexture(texNum)
	gl.BindTexture(gl.TEXTURE_2D, texture)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA,
		int32(rgba.Rect.Size().X), int32(rgba.Rect.Size().Y),
		0, gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(rgba.Pix))

	return texture, nil
}

func (t *Texture) Delete() {
	if t.id != 0 {
		gl.BindTexture(gl.TEXTURE_2D, 0)
		gl.DeleteTextures(1, &t.id)
		t.id = 0
	}
}

func (tr *TextRenderer) Draw(tex *Texture, x, y, scale float32) (err error) {
	gl.ActiveTexture(gl.TEXTURE0)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR: %X", e)
	}
	gl.BindTexture(gl.TEXTURE_2D, tex.Texture)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR: %X", e)
	}
	gl.Uniform3f(tr.ScaleLoc, float32(tex.Width)*scale, float32(tex.Height)*scale, 1)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR: %X", e)
	}
	gl.Uniform3f(tr.TransLoc, x, y, 0)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR: %X", e)
	}
	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR: %X", e)
	}
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	if e := gl.GetError(); e != 0 {
		return fmt.Errorf("ERROR: %X", e)
	}
	return nil
}

func (texture Texture) Bind(textureSlot int) {
	if textureSlot > int(gl.TEXTURE31) {
		tlog.Panic("active texture slot too large: ", textureSlot)
	}
	gl.ActiveTexture(uint32(gl.TEXTURE0 + textureSlot))
	Check()
	gl.BindTexture(gl.TEXTURE_2D, uint32(texture))
	Check()
}

func GetGLTexture(img image.Image, smoothing TextureSmoothing) (t uint32, err error) {
	var (
		data   *bytes.Buffer
		bounds image.Rectangle
		width  int
		height int
	)
	if data, err = imageBytes(img); err != nil {
		return
	}
	bounds = img.Bounds()
	width = bounds.Max.X - bounds.Min.X
	height = bounds.Max.Y - bounds.Min.Y
	gl.GenTextures(1, &t)
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt1 ERROR: %s\n", e)
	}
	gl.BindTexture(gl.TEXTURE_2D, t)
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt2 ERROR: %s\n", e)
	}
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, int32(smoothing))
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt3 ERROR: %s\n", e)
	}
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, int32(smoothing))
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt4 ERROR: %s\n", e)
	}
	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, int32(width), int32(height), 0, gl.RGBA, gl.UNSIGNED_INT_8_8_8_8, gl.Ptr(data.Bytes()))
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt5 ERROR: %s\n", e)
	}
	gl.GenerateMipmap(gl.TEXTURE_2D)
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt6 ERROR: %s\n", e)
	}
	gl.BindTexture(gl.TEXTURE_2D, 0)
	if e := gl.GetError(); e != 0 {
		fmt.Printf("ggt7 ERROR: %s\n", e)
	}
	return
}

func (r *EffectsRenderer) Delete() error {
	gl.BindTexture(gl.TEXTURE_2D, 0)
	gl.BindFramebuffer(gl.FRAMEBUFFER, 0)
	gl.BindRenderbuffer(gl.RENDERBUFFER, 0)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	gl.DeleteFramebuffers(1, &r.framebuffer)
	gl.DeleteTextures(1, &r.texture)
	gl.DeleteBuffers(1, &r.coords)
	return r.GetError()
}

func (r *GlowRenderer) Delete() error {
	gl.BindTexture(gl.TEXTURE_2D, 0)
	gl.BindFramebuffer(gl.FRAMEBUFFER, 0)
	gl.BindRenderbuffer(gl.RENDERBUFFER, 0)
	gl.BindBuffer(gl.ARRAY_BUFFER, 0)
	gl.DeleteFramebuffers(1, &r.GlowFb)
	gl.DeleteTextures(1, &r.GlowTex)
	gl.DeleteFramebuffers(1, &r.BlurFb)
	gl.DeleteTextures(1, &r.BlurTex)
	gl.DeleteBuffers(1, &r.coords)
	return r.GetError()
}

func (renderObject *RenderObject) Render() {
	gl.BindVertexArray(renderObject.vao)
	gl.BindBuffer(gl.ARRAY_BUFFER, renderObject.vbo)
	gl.BindBuffer(gl.ELEMENT_ARRAY_BUFFER, renderObject.ebo)
	gl.UseProgram(renderObject.shaderProgram)

	// Binding the texture.
	gl.ActiveTexture(gl.TEXTURE0)
	gl.BindTexture(gl.TEXTURE_2D, renderObject.texture)
	gl.BindFragDataLocation(renderObject.shaderProgram, 0, gl.Str("outputColor\x00"))

	// Drawing the object.
	gl.DrawElements(gl.TRIANGLES, 6, gl.UNSIGNED_INT, nil)
}

func createTexture(textureUnit uint32, rgba *image.RGBA) (uint32, error) {
	var texture uint32
	gl.GenTextures(1, &texture)
	gl.ActiveTexture(textureUnit)
	gl.BindTexture(gl.TEXTURE_2D, texture)

	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)

	gl.TexImage2D(gl.TEXTURE_2D, 0, gl.RGBA, int32(rgba.Rect.Size().X), int32(rgba.Rect.Size().Y), 0, gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(rgba.Pix))

	return texture, nil
}

// Attempting to load a Texture from a given location on the disk.
func LoadTexture(path string) (Texture, error) {
	// Loading the image data.
	imgFile, err := os.Open(path)
	if err != nil {
		return 0, err
	}

	img, _, err := image.Decode(imgFile)
	if err != nil {
		return 0, err
	}

	rgba := image.NewRGBA(img.Bounds())
	if rgba.Stride != rgba.Rect.Size().X*4 {
		return 0, errors.New("Unsupported stride.")
	}
	draw.Draw(rgba, rgba.Bounds(), img, image.Point{0, 0}, draw.Src)

	// Generating and populating the texture.
	var texture uint32

	gl.GenTextures(1, &texture)
	gl.ActiveTexture(gl.TEXTURE0)
	gl.BindTexture(gl.TEXTURE_2D, texture)

	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.LINEAR)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.LINEAR)

	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.CLAMP_TO_EDGE)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.CLAMP_TO_EDGE)

	gl.TexImage2D(
		gl.TEXTURE_2D,
		0,
		gl.RGBA,
		int32(rgba.Rect.Size().X),
		int32(rgba.Rect.Size().Y),
		0,
		gl.RGBA,
		gl.UNSIGNED_BYTE,
		gl.Ptr(rgba.Pix))

	return Texture(texture), nil
}