我正在尝试渲染png图像的纹理，并使用OpenglES 1.0在Swift上绘制字符串作为纹理。但是没有一个例子我用Google搜索并发现在这里工作。我花了足够的时间来完成它，我需要弄明白这一点。
在屏幕上只显示非纹理抽屉，我删除了所有基于三角形的抽屉，没有关于相机角度或视图的问题，问题是关于纹理渲染。
感谢任何人都可以帮助我，这里是我用于绘制png到纹理的简化代码，但没有显示任何内容，甚至没有显示白框;
这是渲染器类;
import GLKit
import SWXMLHash
class MapViewController: GLKViewController {
@IBOutlet var glView: GLKView!
var rViewController : UIViewController? = nil
var context : EAGLContext!
var ratio : Float!
var size : Float!
override func viewDidLoad() {
super.viewDidLoad()
self.context = EAGLContext.init(API: EAGLRenderingAPI.OpenGLES1)
if self.context == nil {
Util.log("failed to create context for self")
}
glView.context = self.context
EAGLContext.setCurrentContext(self.context)
glClearColor(0.95, 0.95, 0.95, 0.5)
glDisable(GLenum(GL_CULL_FACE))
glEnable(GLenum(GL_DEPTH_TEST))
glEnable(GLenum(GL_BLEND))
glBlendFunc(GLenum(GL_SRC_ALPHA), GLenum(GL_ONE_MINUS_SRC_ALPHA))
}
override func viewWillLayoutSubviews() {
if firstInit {
let width = glView.frame.size.width
let height = glView.frame.size.height
glViewport(0, 0, Int32(width), Int32(height))
let fieldOfView = GLKMathDegreesToRadians(60)
glEnable(GLenum(GL_NORMALIZE))
self.ratio = Float(width)/Float(height)
glMatrixMode(GLenum(GL_PROJECTION))
glLoadIdentity()
size = zNear * Float(tan(Double(fieldOfView/2.0)))
glFrustumf(-size, size, -size / (ratio), size / (ratio), zNear, zFar)
glMatrixMode(GLenum(GL_MODELVIEW))
glLoadIdentity()
}
}
override func glkView(view: GLKView, drawInRect rect: CGRect) {
glPushMatrix()
glClear(GLbitfield(GL_COLOR_BUFFER_BIT))
glClear(GLbitfield(GL_DEPTH_BUFFER_BIT))
glMatrixMode(GLenum(GL_MODELVIEW))
glLoadIdentity()
glEnableClientState(GLenum(GL_VERTEX_ARRAY))
glEnableClientState(GLenum(GL_COLOR_ARRAY))
glEnable(GLenum(GL_TEXTURE_2D))
// glEnable(GLenum(GL_BLEND))
// glEnableClientState(GLenum(GL_NORMAL_ARRAY))
glEnableClientState(GLenum(GL_TEXTURE_COORD_ARRAY))
let fl = CGPoint(x: 0, y: 0)
let drawer = IconDrawer(x: 0, y: 0, z: 0, size:150, roomCoords: fl, exampleimage)
drawer.draw()
glDisable(GLenum(GL_TEXTURE_2D))
glDisableClientState(GLenum(GL_TEXTURE_COORD_ARRAY))
glDisableClientState(GLenum(GL_VERTEX_ARRAY));
glDisableClientState(GLenum(GL_COLOR_ARRAY));
glPopMatrix();
}
}
这是抽屉类;
import Foundation
class IconDrawer : Mesh {
let normals : [GLfloat] = [
0.0, 0.0, 1.0,
0.0, 0.0, 1.0,
0.0, 0.0, 1.0,
0.0, 0.0, 1.0 ]
let textureCoordinates : [Float] = [0.0, 1.0,
1.0, 1.0,
1.0, 0.0,
0.0, 0.0]
let indices = [0, 1, 2, 0, 2, 3]
var coordinates : CGPoint? = nil
var texture:GLuint=0
static var currentScreenMid = CGPoint(x: 0, y: 0)
init(x : Float, y : Float, z : Float, size : Int, roomCoords : CGPoint, imageName : String) {
super.init()
// Mapping coordinates for the vertices
self.coordinates = roomCoords
let w = Float((size)/1000);
let h = Float((size)/1000);
let vertices : [Float] = [-w+x, -h+y, z+Zunit,
w+x, -h+y, z+Zunit,
w+x, h+y, z+Zunit,
-w+x, h+y, z+Zunit]
setIndices(indices);
setVertices(vertices);
setTextureCoordinates(textureCoordinates);
//PART 1 LOAD PNG
let image = UIImage(named : imageName)
let iwidth = CGImageGetWidth(image?.CGImage)
let iheight = CGImageGetHeight(image?.CGImage)
let imageData = malloc(iwidth * iheight * 4)
let bitmapInfo = CGBitmapInfo(rawValue: CGImageAlphaInfo.PremultipliedLast.rawValue)
let imageContext : CGContextRef = CGBitmapContextCreate(imageData, iwidth, iheight, 8, iwidth * 4, CGColorSpaceCreateDeviceRGB(), bitmapInfo.rawValue)!
CGContextClearRect(imageContext, CGRectMake(0, 0, CGFloat(iwidth), CGFloat(iheight)))
CGContextTranslateCTM(imageContext, 0, CGFloat((iheight - iheight)))
CGContextDrawImage(imageContext, CGRectMake(0.0, 0.0, CGFloat(iwidth), CGFloat(iheight)), image?.CGImage)
glTexImage2D(GLenum(GL_TEXTURE_2D), GLint(0), GL_RGBA, Int32(iwidth), Int32(iheight), GLint(0), GLenum(GL_RGBA), GLenum(GL_UNSIGNED_BYTE), imageData)
self.w = GLsizei(Int(image!.size.width))
self.h = GLsizei(Int(image!.size.height))
loadBitmap(imageData)
fl.bitmaps.append(imageData)
//PART 2 CREATE TEXTURE WITH THE IMAGE DATA
glGenTextures(1, &texture)
glBindTexture(GLenum(GL_TEXTURE_2D), texture)
glTexImage2D(GLenum(GL_TEXTURE_2D), Int32(0), GL_RGBA, GLsizei(Int(image!.size.width)), GLsizei(Int(image!.size.height)), Int32(0), GLenum(GL_RGBA), GLenum(GL_UNSIGNED_BYTE), imageData)
glTexParameteri(GLenum(GL_TEXTURE_2D), GLenum(GL_TEXTURE_MIN_FILTER), GLint(GL_LINEAR))
glTexParameteri(GLenum(GL_TEXTURE_2D), GLenum(GL_TEXTURE_MAG_FILTER), GLint(GL_LINEAR))
if image != nil {
let imageRect = CGRectMake(0.0, 0.0, image!.size.width, image!.size.height);
UIGraphicsBeginImageContextWithOptions(image!.size, false, UIScreen.mainScreen().scale)
image?.drawInRect(imageRect)
UIGraphicsEndImageContext();
}
}
override func draw() {
//PART 3 RENDER
glEnableClientState(GLenum(GL_VERTEX_ARRAY));
glEnableClientState(GLenum(GL_NORMAL_ARRAY));
glEnableClientState(GLenum(GL_TEXTURE_COORD_ARRAY));
glEnable(UInt32(GL_TEXTURE_2D));
glEnable(UInt32(GL_BLEND));
glBlendFunc(UInt32(GL_SRC_ALPHA), UInt32(GL_ONE_MINUS_SRC_ALPHA));
Drawer.printGLErrors()
glBindTexture(GLenum(GL_TEXTURE_2D), texture)
Drawer.printGLErrors()
glVertexPointer(Int32(2), GLenum(GL_FLOAT), GLsizei(0), self.mVerticesBuffer!)
Drawer.printGLErrors()
glNormalPointer(GLenum(GL_FLOAT), GLsizei(0), normals)
Drawer.printGLErrors()
glTexCoordPointer(Int32(2), GLenum(GL_FLOAT), GLsizei(0), textureCoordinates)
Drawer.printGLErrors()
glDrawArrays(GLenum(GL_TRIANGLE_STRIP), 0, 4)
Drawer.printGLErrors()
}
}
答案 0 :(得分：2)
您面临的问题是不支持开箱即用的非POT（2的幂）纹理。我相信有一些扩展，但我不打扰。
无论如何，纹理尺寸必须是POT（2,4,8,16 ......），所以你有两个选择。您可以在获取原始图像数据指针时创建POT上下文，并将图像大小调整为在过程中缩放图像所需的POT大小。更常见的方法是使用NULL数据指针创建足够大的纹理，然后使用glTexSubImage和原始图像大小参数将数据发送到纹理。此过程还要求您更改纹理坐标，而不是1.0，您将拥有imageWidth/textureWidth，高度相同。第二个过程需要更多的努力，但通常用于升级到纹理图集程序（将多个图像放在同一纹理上）。
然后，最快的程序只是在Photoshop中调整图像大小或者例如128x128。只是POT尺寸的注释不应该是相同的，128x64也应该是有效的。