所以我一直在创建游戏，我想用着色器支持opengl 2.1版。我根据在线教程实现了我的能力，当我运行游戏时没有任何显示，注意：如果着色器更改为最新版本，我支持一切正常..（我使用VBO）
以下是着色器：
片段着色器：
uniform sampler2D texture1;
varying vec4 pass_Color;
varying vec2 pass_TextureCoord;
void main(void) {
gl_FragColor = pass_Color;
vec2 texcoord = vec2(pass_TextureCoord.xy);
vec4 color = texture2D(texture1, texcoord) * pass_Color ;
gl_FragColor = color;
}
* 顶点着色器：*
attribute vec4 in_Position;
attribute vec4 in_Color;
attribute vec2 in_TextureCoord;
varying vec4 pass_Color;
varying vec2 pass_TextureCoord;
uniform vec4 cameraPos;
uniform mat4 projection;
void main(void) {
gl_Position = ( (vec4(cameraPos.x*projection[0][0],cameraPos.y*projection[1][1],cameraPos.z*projection[0][0],cameraPos.w*projection[0][0])) + (in_Position * projection)) ;
pass_Color = in_Color;
pass_TextureCoord = in_TextureCoord;
}
注意：在顶点着色器中我计算位置，这是正确的，因为我使用这条精确的线来计算较新的着色器中的位置，并且效果很好。
我如何创建VBO：
vboId = GL15.glGenBuffers();
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, vboId);
GL15.glBufferData(GL15.GL_ARRAY_BUFFER, vboData, GL15.GL_STATIC_DRAW);
// Put the position coordinates in attribute list 0
GL20.glVertexAttribPointer(GL20.glGetAttribLocation(game.getResourceManager().getShaderProgramID(), "in_Position"), TexturedVertex.positionElementCount, GL11.GL_FLOAT,
false, TexturedVertex.stride, TexturedVertex.positionByteOffset);
// Put the color components in attribute list 1
GL20.glVertexAttribPointer(GL20.glGetAttribLocation(game.getResourceManager().getShaderProgramID(), "in_Color"), TexturedVertex.colorElementCount, GL11.GL_FLOAT,
false, TexturedVertex.stride, TexturedVertex.colorByteOffset);
// Put the texture coordinates in attribute list 2
GL20.glVertexAttribPointer(GL20.glGetAttribLocation(game.getResourceManager().getShaderProgramID(), "in_TextureCoord"), TexturedVertex.textureElementCount, GL11.GL_FLOAT,
false, TexturedVertex.stride, TexturedVertex.textureByteOffset);
GL15.glBindBuffer(GL15.GL_ARRAY_BUFFER, 0);
这是我呈现的方式:(留下无用的东西）
GL20.glUseProgram(game.getResourceManager().getShaderProgramID());
//Send the camera location and the projection matrix
int loc3 = GL20.glGetUniformLocation(game.getResourceManager().getShaderProgramID(), "projection");
FloatBuffer buf2 = BufferUtils.createFloatBuffer(16);
GL11.glGetFloat(GL11.GL_PROJECTION_MATRIX,buf2);
GL20.glUniformMatrix4(loc3,false,buf2);
int loc4 = GL20.glGetUniformLocation(game.getResourceManager().getShaderProgramID(), "cameraPos");
GL20.glUniform4f(loc4, game.getGameCamera().getCameraLocation().x*-1*Constants.PHYS_PIXEL_TO_METER_RATIO, game.getGameCamera().getCameraLocation().y*-1*Constants.PHYS_PIXEL_TO_METER_RATIO, 0,1);
////////////////////////////RENDERING\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\\
GL11.glBindTexture(GL11.GL_TEXTURE_2D, textureID);
GL20.glEnableVertexAttribArray(0);
GL20.glEnableVertexAttribArray(1);
GL20.glEnableVertexAttribArray(2);
// Bind to the index VBO that has all the information about the order of the vertices
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, VBOIndeciesID);
// Draw the vertices
GL11.glDrawElements(GL11.GL_TRIANGLES,6 , GL11.GL_UNSIGNED_INT, 0);
// Put everything back to default (deselect)
GL15.glBindBuffer(GL15.GL_ELEMENT_ARRAY_BUFFER, 0);
GL20.glDisableVertexAttribArray(0);
GL20.glDisableVertexAttribArray(1);
GL20.glDisableVertexAttribArray(2);
GL20.glUseProgram(0);
修改
我检查了几乎所有我遗漏的错误，因为它没有给我输出。这是我检查错误的方法：
private void exitOnGLError(String errorMessage) { //Method to check if any opengl errors occured
int errorValue = GL11.glGetError();
if (errorValue != GL11.GL_NO_ERROR) {
String errorString = GLU.gluErrorString(errorValue);
System.err.println("ERROR - " + errorMessage + ": " + errorString);
if (Display.isCreated()) Display.destroy();
System.exit(-1);
}
}
关联着色器：
loadShader("res/shaders/vert21.glsl",GL20.GL_VERTEX_SHADER);
loadShader("res/shaders/frag21.glsl",GL20.GL_FRAGMENT_SHADER);
shaderProgramID = GL20.glCreateProgram(); //Create a new shader program
for (Integer id : shaders) {
GL20.glAttachShader(shaderProgramID, id); //attach all the custom shaders to the program
}
// Position information will be attribute 0
GL20.glBindAttribLocation(shaderProgramID, 0, "in_Position");
// Color information will be attribute 1
GL20.glBindAttribLocation(shaderProgramID, 1, "in_Color");
// Textute information will be attribute 2
GL20.glBindAttribLocation(shaderProgramID, 2, "in_TextureCoord");
GL20.glLinkProgram(shaderProgramID); //Link the program to lwjgl
GL20.glValidateProgram(shaderProgramID); //Compile and make sure program was setup correctly
GL20.glUseProgram(shaderProgramID); //Use the program so we can pick the texture unit before continuing
setTextureUnit0(shaderProgramID); //pick the unit and set it in the shader to use
加载和编译：
StringBuilder shaderSource = new StringBuilder();
int shaderID = 0;
try { //Read shader
BufferedReader reader = new BufferedReader(new InputStreamReader(ClassLoader.getSystemResourceAsStream(filename)));
String line;
while ((line = reader.readLine()) != null) {
shaderSource.append(line).append("\n");
}
reader.close();
} catch (IOException e) {
System.err.println("Could not read file.");
Logger.getGlobal().log(Level.WARNING, e.getMessage(), e);
System.exit(-1);
} catch (NullPointerException e) {
try {
BufferedReader reader = new BufferedReader(new InputStreamReader( new FileInputStream(filename)));
String line;
while ((line = reader.readLine()) != null) {
shaderSource.append(line).append("\n");
}
reader.close();
} catch (IOException e1) {
e1.printStackTrace(); //To change body of catch statement use File | Settings | File Templates.
}
}
shaderID = GL20.glCreateShader(type); //Create shader
GL20.glShaderSource(shaderID, shaderSource); //Link source
GL20.glCompileShader(shaderID); //Compile
//Check if compiled correctly
if (GL20.glGetShaderi(shaderID, GL20.GL_COMPILE_STATUS) == GL11.GL_FALSE) {
System.err.println(shaderID+" | Shader wasn't able to be compiled correctly.");
System.out.println(GL20.glGetShaderInfoLog(shaderID,GL20.glGetShaderi(shaderID,GL20.GL_INFO_LOG_LENGTH)));
}
this.exitOnGLError("loadShader");