Esempio n. 1
0
// Arrays mode uses vertex arrays which involves gl*Pointer calls and
// directly passing in the vertex data on every render pass. This is slower
// than using VBO's, because the data has to be uploaded to the GPU on every
// render pass, but it is useful for older systems where glBufferData is
// not available.
func (mb *MeshBuffer) renderArrays(mode gl.GLenum, m Mesh, pa, ca, na, ta, ia *Attr) {
	ps, pc := m[mbPositionKey][0], m[mbPositionKey][1]
	is, ic := m[mbIndexKey][0], m[mbIndexKey][1]
	cc := m[mbColorKey][1]
	nc := m[mbNormalKey][1]
	tc := m[mbTexCoordKey][1]

	gl.PushClientAttrib(gl.CLIENT_VERTEX_ARRAY_BIT)
	defer gl.PopClientAttrib()

	if pc > 0 {
		gl.EnableClientState(gl.VERTEX_ARRAY)
		defer gl.DisableClientState(gl.VERTEX_ARRAY)
		gl.VertexPointer(pa.size, pa.typ, 0, pa.ptr(0))
	}

	if cc > 0 {
		gl.EnableClientState(gl.COLOR_ARRAY)
		defer gl.DisableClientState(gl.COLOR_ARRAY)
		gl.ColorPointer(ca.size, ca.typ, 0, ca.ptr(0))
	}

	if nc > 0 {
		gl.EnableClientState(gl.NORMAL_ARRAY)
		defer gl.DisableClientState(gl.NORMAL_ARRAY)
		gl.NormalPointer(na.typ, 0, na.ptr(0))
	}

	if tc > 0 {
		gl.EnableClientState(gl.TEXTURE_COORD_ARRAY)
		defer gl.DisableClientState(gl.TEXTURE_COORD_ARRAY)
		gl.TexCoordPointer(ta.size, ta.typ, 0, ta.ptr(0))
	}

	if ic > 0 {
		gl.EnableClientState(gl.INDEX_ARRAY)
		defer gl.DisableClientState(gl.INDEX_ARRAY)
		gl.IndexPointer(ia.typ, 0, ia.ptr(0))
		gl.DrawElements(mode, ic, ia.typ, ia.ptr(is*ia.size))
	} else {
		gl.DrawArrays(mode, ps, pc)
	}
}
Esempio n. 2
0
// renderBuffered uses VBO's. This is the preferred mode for systems
// where shader support is not present or deemed necessary.
func (mb *MeshBuffer) renderBuffered(mode gl.GLenum, m Mesh, pa, ca, na, ta, ia *Attr) {
	ps, pc := m[mbPositionKey][0], m[mbPositionKey][1]
	is, ic := m[mbIndexKey][0], m[mbIndexKey][1]
	cc := m[mbColorKey][1]
	nc := m[mbNormalKey][1]
	tc := m[mbTexCoordKey][1]

	if pc > 0 {
		gl.EnableClientState(gl.VERTEX_ARRAY)
		defer gl.DisableClientState(gl.VERTEX_ARRAY)

		pa.bind()
		if pa.Invalid() {
			pa.buffer()
		}
		gl.VertexPointer(pa.size, pa.typ, 0, uintptr(0))
		pa.unbind()
	}

	if cc > 0 {
		gl.EnableClientState(gl.COLOR_ARRAY)
		defer gl.DisableClientState(gl.COLOR_ARRAY)

		ca.bind()
		if ca.Invalid() {
			ca.buffer()
		}
		gl.ColorPointer(ca.size, ca.typ, 0, uintptr(0))
		ca.unbind()
	}

	if nc > 0 {
		gl.EnableClientState(gl.NORMAL_ARRAY)
		defer gl.DisableClientState(gl.NORMAL_ARRAY)

		na.bind()
		if na.Invalid() {
			na.buffer()
		}
		gl.NormalPointer(na.typ, 0, uintptr(0))
		na.unbind()
	}

	if tc > 0 {
		gl.EnableClientState(gl.TEXTURE_COORD_ARRAY)
		defer gl.DisableClientState(gl.TEXTURE_COORD_ARRAY)

		ta.bind()
		if ta.Invalid() {
			ta.buffer()
		}
		gl.TexCoordPointer(ta.size, ta.typ, 0, uintptr(0))
		ta.unbind()
	}

	if ic > 0 {
		ia.bind()

		if ia.Invalid() {
			ia.buffer()
		}

		gl.PushClientAttrib(gl.CLIENT_VERTEX_ARRAY_BIT)
		gl.DrawElements(mode, ic, ia.typ, uintptr(is*ia.stride))
		gl.PopClientAttrib()
		ia.unbind()
	} else {
		pa.bind()
		gl.PushClientAttrib(gl.CLIENT_VERTEX_ARRAY_BIT)
		gl.DrawArrays(mode, ps, pc)
		gl.PopClientAttrib()
		pa.unbind()
	}
}
Esempio n. 3
0
func (r *RenderTarget) Render(verts []Vertex, primType PrimitiveType, states RenderStates) {
	// Nothing to draw?
	if len(verts) == 0 {
		return
	}

	// First set the persistent OpenGL states if it's the very first call
	if !r.glStatesSet {
		r.resetGlStates()
	}

	// Check if the vertex count is low enough so that we can pre-transform them
	useVertexCache := len(verts) <= vertexCacheSize
	if useVertexCache {
		// Pre-transform the vertices and store them into the vertex cache
		for i := 0; i < len(verts); i++ {
			r.vpCache[i] = states.Transform.TransformPoint(verts[i].Pos)
			r.vcCache[i] = verts[i].Color
			r.vtCache[i] = verts[i].TexCoords
		}

		// Since vertices are transformed, we must use an identity transform to render them
		if !r.useVertexCache {
			r.applyTransform(IdentityTransform())
		}
	} else {
		r.applyTransform(states.Transform)
	}

	// Apply the view
	if r.viewChanged {
		r.applyCurrentView()
	}

	// Apply the blend mode
	if states.BlendMode != r.lastBlendMode {
		r.applyBlendMode(states.BlendMode)
	}

	// Apply the texture
	var textureId uint64
	if states.Texture != nil {
		textureId = states.Texture.cacheId
	}
	if textureId != r.lastTextureId {
		r.applyTexture(states.Texture)
	}

	// Apply the shader
	// TODO
	/*if states.shader {
		applyShader(states.shader);
	}*/

	// #########################################

	if !useVertexCache {
		// Find the OpenGL primitive type
		modes := [...]gl.GLenum{gl.POINTS, gl.LINES, gl.LINE_STRIP, gl.TRIANGLES,
			gl.TRIANGLE_STRIP, gl.TRIANGLE_FAN, gl.QUADS}
		mode := modes[primType]

		gl.Begin(mode)

		for i, _ := range verts {
			gl.TexCoord2f(verts[i].TexCoords.X, verts[i].TexCoords.Y)
			gl.Color4f(float32(verts[i].Color.R)/255, float32(verts[i].Color.G)/255,
				float32(verts[i].Color.B)/255, float32(verts[i].Color.A)/255)
			gl.Vertex2f(verts[i].Pos.X, verts[i].Pos.Y)
		}

		gl.End()
	}

	// #########################################

	// Setup the pointers to the vertices' components
	// ... and if we already used it previously, we don't need to set the pointers again
	if useVertexCache {
		if !r.useVertexCache {
			gl.VertexPointer(2, gl.FLOAT, 0, r.vpCache[:])
			gl.ColorPointer(4, gl.UNSIGNED_BYTE, 0, r.vcCache[:])
			gl.TexCoordPointer(2, gl.FLOAT, 0, r.vtCache[:])
		}

		// Find the OpenGL primitive type
		modes := [...]gl.GLenum{gl.POINTS, gl.LINES, gl.LINE_STRIP, gl.TRIANGLES,
			gl.TRIANGLE_STRIP, gl.TRIANGLE_FAN, gl.QUADS}
		mode := modes[primType]

		// Draw the primitives
		gl.DrawArrays(mode, 0, len(verts))
	}

	// Unbind the shader, if any
	// TODO
	/*if (states.shader) {
		r.applyShader(nil)
	}*/

	// Update the cache
	r.useVertexCache = useVertexCache
}