Exemplo n.º 1
0
func (polyline *polyLine) drawTriangles(is_looping bool) {
	var overdraw []mgl32.Vec2
	if polyline.overdraw {
		overdraw = polyline.renderOverdraw(is_looping)
	}

	numindices := int(math.Max(float64(len(polyline.vertices)/4), float64(len(overdraw)/4)))
	indices := newAltQuadIndices(numindices)

	prepareDraw(nil)
	bindTexture(gl_state.defaultTexture)
	useVertexAttribArrays(attribflag_pos)
	gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(polyline.vertices))
	gl.DrawElements(gl.TRIANGLES, (len(polyline.vertices)/4)*6, gl.UNSIGNED_SHORT, gl.Ptr(indices))
	if polyline.overdraw {
		c := GetColor()
		colors := polyline.generateColorArray(len(overdraw), c)
		useVertexAttribArrays(attribflag_pos | attribflag_color)
		gl.VertexAttribPointer(attrib_color, 4, gl.UNSIGNED_BYTE, true, 0, gl.Ptr(colors))
		gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(overdraw))
		gl.DrawElements(gl.TRIANGLES, (len(overdraw)/4)*6, gl.UNSIGNED_SHORT, gl.Ptr(indices))
		SetColorC(c)
	}

	indices.Release()
}
Exemplo n.º 2
0
// drawv will take in verticies from the public draw calls and draw the texture
// with the verticies and the model matrix
func (texture *Texture) drawv(model *mgl32.Mat4, vertices []float32) {
	prepareDraw(model)
	bindTexture(texture.getHandle())
	useVertexAttribArrays(attribflag_pos | attribflag_texcoord)

	gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 4*4, gl.Ptr(vertices))
	gl.VertexAttribPointer(attrib_texcoord, 2, gl.FLOAT, false, 4*4, gl.Ptr(&vertices[2]))

	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, 4)
}
Exemplo n.º 3
0
// Point will draw a point on the screen at x, y position. The size of the point
// is dependant on the point size set with SetPointSize.
func Point(x, y float32) {
	prepareDraw(nil)
	bindTexture(gl_state.defaultTexture)
	useVertexAttribArrays(attribflag_pos)
	gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr([]float32{x, y}))
	gl.DrawArrays(gl.POINTS, 0, 1)
}
Exemplo n.º 4
0
// Circlep will draw a circle at x, y with a radius as specified.
// radiusx and radiusy will specify how much the width will be along those axis
// points specifies how many points should be generated in the arc.
// If it is lower it will look jagged. If it is higher it will hit performace.
// The drawmode specifies either a fill or line draw
func Ellipsep(mode DrawMode, x, y, radiusx, radiusy float32, points int) {
	two_pi := math.Pi * 2.0
	if points <= 0 {
		points = 1
	}

	angle_shift := float32(two_pi) / float32(points)
	phi := float32(0.0)

	coords := make([]float32, 2*(points+1))
	for i := 0; i < points; i++ {
		phi += angle_shift
		coords[2*i+0] = x + radiusx*float32(math.Cos(float64(phi)))
		coords[2*i+1] = y + radiusy*float32(math.Sin(float64(phi)))
	}

	coords[2*points+0] = coords[0]
	coords[2*points+1] = coords[1]

	if mode == LINE {
		PolyLine(coords)
	} else {
		prepareDraw(nil)
		bindTexture(gl_state.defaultTexture)
		useVertexAttribArrays(attribflag_pos)
		gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(coords))
		gl.DrawArrays(gl.TRIANGLE_FAN, 0, len(coords)/2-1)
	}
}
Exemplo n.º 5
0
func (buffer *vertexBuffer) bufferStatic() {
	if buffer.modified_size == 0 {
		return
	}
	// Upload the mapped data to the buffer.
	gl.BufferSubData(gl.ARRAY_BUFFER, buffer.modified_offset*4, buffer.modified_size*4, gl.Ptr(&buffer.data[buffer.modified_offset]))
}
Exemplo n.º 6
0
func (buffer *vertexBuffer) loadVolatile() bool {
	buffer.vbo = gl.CreateBuffer()
	buffer.bind()
	defer buffer.unbind()
	gl.BufferData(gl.ARRAY_BUFFER, len(buffer.data)*4, gl.Ptr(buffer.data), uint32(buffer.usage))
	return true
}
Exemplo n.º 7
0
func (polyline *polyLine) drawTriangleStrip(is_looping bool) {
	prepareDraw(nil)
	bindTexture(gl_state.defaultTexture)
	useVertexAttribArrays(attribflag_pos)
	gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(polyline.vertices))
	gl.DrawArrays(gl.TRIANGLE_STRIP, 0, len(polyline.vertices))
	if polyline.overdraw { // prepare colors:
		c := GetColor()
		overdraw := polyline.renderOverdraw(is_looping)
		colors := polyline.generateColorArray(len(overdraw), c)
		useVertexAttribArrays(attribflag_pos | attribflag_color)
		gl.VertexAttribPointer(attrib_color, 4, gl.UNSIGNED_BYTE, true, 0, gl.Ptr(colors))
		gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(overdraw))
		gl.DrawArrays(gl.TRIANGLE_STRIP, 0, len(overdraw))
		SetColorC(c)
	}
}
Exemplo n.º 8
0
// Polygon will draw a closed polygon with an array in the form of x1, y1, x2, y2, x3, y3, ..... xn, yn
// The drawmode specifies either a fill or line draw
func Polygon(mode DrawMode, coords []float32) {
	coords = append(coords, coords[0], coords[1])
	if mode == LINE {
		PolyLine(coords)
	} else {
		prepareDraw(nil)
		bindTexture(gl_state.defaultTexture)
		useVertexAttribArrays(attribflag_pos)
		gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(coords))
		gl.DrawArrays(gl.TRIANGLE_FAN, 0, len(coords)/2-1)
	}
}
Exemplo n.º 9
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// Set the 'default' texture (id 0) as a repeating white pixel. Otherwise,
// texture2D calls inside a shader would return black when drawing graphics
// primitives, which would create the need to use different "passthrough"
// shaders for untextured primitives vs images.
func createDefaultTexture() {
	gl_state.defaultTexture = gl.CreateTexture()
	bindTexture(gl_state.defaultTexture)

	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MIN_FILTER, gl.NEAREST)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_MAG_FILTER, gl.NEAREST)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_S, gl.REPEAT)
	gl.TexParameteri(gl.TEXTURE_2D, gl.TEXTURE_WRAP_T, gl.REPEAT)

	pix := []byte{255, 255, 255, 255}
	gl.TexImage2D(gl.TEXTURE_2D, 0, 1, 1, gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(pix))
}
Exemplo n.º 10
0
// Arcp is like Arc except that you can define how many points you want to generate
// the arc.
// If it is lower it will look jagged. If it is higher it will hit performace.
// The drawmode specifies either a fill or line draw
func Arcp(mode DrawMode, x, y, radius, angle1, angle2 float32, points int) {
	// Nothing to display with no points or equal angles. (Or is there with line mode?)
	if points <= 0 || angle1 == angle2 {
		return
	}

	// Oh, you want to draw a circle?
	if math.Abs(float64(angle1-angle2)) >= (2.0 * math.Pi) {
		Circlep(mode, x, y, radius, points)
		return
	}

	angle_shift := (angle2 - angle1) / float32(points)
	// Bail on precision issues.
	if angle_shift == 0.0 {
		return
	}

	phi := angle1
	num_coords := (points + 3) * 2
	coords := make([]float32, num_coords)
	coords[0] = x
	coords[num_coords-2] = x
	coords[1] = y
	coords[num_coords-1] = y

	for i := 0; i <= points; i++ {
		phi = phi + angle_shift
		coords[2*(i+1)] = x + radius*float32(math.Cos(float64(phi)))
		coords[2*(i+1)+1] = y + radius*float32(math.Sin(float64(phi)))
	}

	if mode == LINE {
		PolyLine(coords)
	} else {
		prepareDraw(nil)
		bindTexture(gl_state.defaultTexture)
		useVertexAttribArrays(attribflag_pos)
		gl.VertexAttribPointer(attrib_pos, 2, gl.FLOAT, false, 0, gl.Ptr(coords))
		gl.DrawArrays(gl.TRIANGLE_FAN, 0, len(coords)/2-1)
	}
}
Exemplo n.º 11
0
// newImageTexture will generate a texture from an image. It will automatically
// upload the image data to the texture.
func newImageTexture(img image.Image, mipmaps bool) (*Texture, error) {
	bounds := img.Bounds()
	new_texture := newTexture(int32(bounds.Dx()), int32(bounds.Dy()), mipmaps)
	//generate a uniform image and upload to vram
	rgba := image.NewRGBA(img.Bounds())
	draw.Draw(rgba, bounds, img, image.Point{0, 0}, draw.Src)
	bindTexture(new_texture.getHandle())
	gl.TexImage2D(gl.TEXTURE_2D, 0, bounds.Dx(), bounds.Dy(), gl.RGBA, gl.UNSIGNED_BYTE, gl.Ptr(rgba.Pix))

	if new_texture.mipmaps {
		new_texture.generateMipmaps()
	}
	return new_texture, nil
}
Exemplo n.º 12
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func (buffer *vertexBuffer) bufferStream() {
	// "orphan" current buffer to avoid implicit synchronisation on the GPU:
	// http://www.seas.upenn.edu/~pcozzi/OpenGLInsights/OpenGLInsights-AsynchronousBufferTransfers.pdf
	gl.BufferData(gl.ARRAY_BUFFER, len(buffer.data)*4, gl.Ptr(nil), uint32(buffer.usage))
	gl.BufferData(gl.ARRAY_BUFFER, len(buffer.data)*4, gl.Ptr(buffer.data), uint32(buffer.usage))
}
Exemplo n.º 13
0
func (buffer *indexBuffer) drawElementsLocal(mode uint32, offset, size int) {
	gl.DrawElements(gl.Enum(mode), size, gl.UNSIGNED_INT, gl.Ptr(&buffer.data[offset]))
}