public void draw(GL10 gl) {
gl.glFrontFace(GL10.GL_CCW);
gl.glEnable(GL10.GL_CULL_FACE);
gl.glCullFace(GL10.GL_BACK);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
/*
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnable(GL10.GL_BLEND);
gl.glEnable(GL10.GL_LINE_SMOOTH);
*/
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glLineWidth(3.0f);
gl.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
gl.glDrawArrays(GL10.GL_LINE_STRIP, 0, list.size()/3);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisable(GL10.GL_CULL_FACE);
//gl.glDisable(GL10.GL_BLEND);
//gl.glDisable(GL10.GL_LINE_SMOOTH);
}
my code is the following.
if i add this code
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnable(GL10.GL_BLEND);
gl.glEnable(GL10.GL_LINE_SMOOTH);
then i get a very thin (1px) line, and not an antialised line. what is the best way to do its correctly?
I think what you're doing is correct, but are you sure your device supports anti aliasing? Look at this blog post:
http://olofsj.posterous.com/playing-with-android-and-opengl
Related
I use 2D sprite texture applied to a square with transparent or semi-transparent area but I can't see anything through them (except the background) if there are other textures behind. I can see the background image because I use a transparent GLSurfaceView, the background is applied in a ImageView behind the GLSurfaceView.
My problem in an image:
Actually I use this code in the onSurfaceCreated method:
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glClearDepthf(1.0f);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glDepthFunc(GL10.GL_LEQUAL);
gl.glHint(GL10.GL_PERSPECTIVE_CORRECTION_HINT, GL10.GL_NICEST);
this in onDrawFrame method:
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
mObject1.draw(gl);
mObject2.draw(gl);
and this in draw method of mObject1 and mObject2:
gl.glPushMatrix();
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
gl.glTranslatef((float) mPosition.getX(), (float) mPosition.getY(), 0f);
float scaleFactor = (float) (2 * mRadius);
gl.glScalef(scaleFactor, scaleFactor, 0);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glColor4f (1f, 1.0f, 1, 1f);
gl.glFrontFace(GL10.GL_CW);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glPopMatrix();
after
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
put
gl.glEnable(GL10.GL_BLEND);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
I am attempting to draw a 2D square on a GLSurfaceView in 2D mode. I can draw the object in 3D mode and have tested that the square is out in 3D space. I then try to configure the matrix for 2d drawing and when I attempt to draw my object nothing appears.
My GLSurfaceView instance implements GLSurfaceView.Renderer.
I've broken the setup into two functions:
private void prepare3Ddrawing(GL10 gl)
{
gl.glLoadIdentity();
gl.glViewport(0, 0, getWidth(), getHeight());
gl.glDisable(GL10.GL_DITHER);
gl.glEnable(GL10.GL_DEPTH_TEST);
gl.glEnable(GL10.GL_CULL_FACE);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
GLU.gluPerspective(gl, 45.0f, (float)getWidth()/(float)getHeight(),0.1f,100.0f);
}
private void prepare2Ddrawing(GL10 gl)
{
gl.glDisable(GL10.GL_CULL_FACE);
gl.glDisable(GL10.GL_DEPTH_TEST);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glLoadIdentity();
GLU.gluOrtho2D(gl,0,getWidth(), 0, getHeight());
gl.glScalef(1, -1, 1);
gl.glTranslatef(0, -getHeight(), 0);
gl.glMatrixMode(GL10.GL_MODELVIEW);
}
And here is my draw method...
public void onDrawFrame(GL10 gl)
{
gl.glClear(GL10.GL_DEPTH_BUFFER_BIT|GL10.GL_COLOR_BUFFER_BIT);
prepare3Ddrawing(gl);
camera.draw(gl);
go2d.draw(gl);
prepare2Ddrawing(gl);
go2d.draw(gl);
}
and finally, my go2d object is an instance of an object I created called GameObject2d. It's draw method looks like this...
#Override
public void draw(GL10 gl)
{
super.draw(gl);
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glEnable(GL10.GL_ALPHA_TEST);
gl.glAlphaFunc(GL10.GL_GREATER, 0.0f);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glTexCoordPointer(2,GL10.GL_FLOAT,0,textureBuffer);
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureID);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnable(GL10.GL_BLEND);
gl.glFrontFace(GL10.GL_CW);
//gl.glEnable(GL10.GL_CULL_FACE);
gl.glCullFace(GL10.GL_BACK);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glDrawElements(GL10.GL_TRIANGLES, 6, GL10.GL_UNSIGNED_SHORT, indexBuffer);
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glDisable(GL10.GL_CULL_FACE);
gl.glDisable(GL10.GL_ALPHA_TEST);
gl.glDisable(GL10.GL_TEXTURE_2D);
}
Does anyone have any ideas? Again, I am still able to see the 3D rendered version of the go2D object, but I do not see the 2D version.
Thanks.
As you don't include any data, I can only propose two methods to debug the issue.
Step 1: try to force your 2d - perspective matrix and modelview matrix to be Identity Matrices. Then if you force your Square data vertices inside the clip space (e.g.
x,y = +-1 or x,y= +-0.75, z=0, you should see a square appearing in the screen.
Step 2: now that the data model is correct, check what your model view and perspective matrices do: multiply each of your square vertices (x,y,z, w=1) with ModelView Matrix * CameraMatrix * PerspectiveMatrix. What do you get? Are the x,y,z much outside |w| ?
I am a newbie with opengl on android. I am trying to draw two different shapes. Shape one has a texture while shape two is supposed to have a color, lets say green. When I run the application, the first shape gets its texture but has also the green color. The texture itself is turned greenish in color. Shape two is green as i wanted. Here is my draw method:
public void draw(GL10 gl) {
gl.glBindTexture(GL10.GL_TEXTURE_2D, textures[0]);
//My first shape
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glPushMatrix();
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, vertices.length / 3);
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glPopMatrix();
//My second shape
gl.glPushMatrix();
//Setting the color green
gl.glColor4f(0.0f, 1.0f, 0.0f, 0.5f);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, locvertexBuffer);
gl.glDrawArrays(GL10.GL_TRIANGLE_STRIP, 0, locvertices.length / 3);
gl.glPopMatrix();
gl.glDisableClientState(GL10.GL_VERTEX_ARRAY);
}
Can anyone help me with this?
Try to put gl.glColor4f(1.0f, 1.0f, 1.0f, 1.0f); before drawing the first shape
OR
use gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_REPLACE);
after you bind the texture
This question already has answers here:
Closed 11 years ago.
Possible Duplicate:
How to get rid of Jagged edges in Android OpenGL ES?
I want to do Antialiasing in my appliction.But it doesn't work no matter what I did.
My code is
public void onSurfaceCreated(GL10 gl, EGLConfig config){
g10 = gl;
gl.glClearColor(0f, 0, 0.0f, 1.0f);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glTexParameterx(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S,
GL10.GL_REPEAT);
gl.glTexParameterx(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T,
GL10.GL_REPEAT);
gl.glSampleCoverage(1.f, true);
gl.glEnable(GL10.GL_DITHER);
gl.glEnable(GL10.GL_MULTISAMPLE);
gl.glEnable(GL10.GL_POINT_SMOOTH);
gl.glEnable(GL10.GL_LINE_SMOOTH);
gl.glEnable(GL10.GL_SAMPLE_COVERAGE);
gl.glPointSize(8);
gl.glLineWidth(5);
gl.glHint(GL10.GL_POINT_SMOOTH_HINT, GL10.GL_NICEST); // Make round points, not square points
gl.glHint(GL10.GL_LINE_SMOOTH_HINT, GL10.GL_NICEST); // Antialias the lines
}
public void draw(GL10 gl){
gl.glClearColor(0f, 0, 0.0f, 1.0f);
gl.glClear(GL10.GL_COLOR_BUFFER_BIT | GL10.GL_DEPTH_BUFFER_BIT);
gl.glTexEnvf(GL10.GL_TEXTURE_ENV, GL10.GL_TEXTURE_ENV_MODE, GL10.GL_MODULATE);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnable(GL10.GL_TEXTURE_2D);
gl.glEnable(GL10.GL_BLEND);
gl.glBindTexture(GL10.GL_TEXTURE_2D, mTexture[0]);
gl.glFrontFace(GL10.GL_CCW);
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, m_TexBuffer[i]);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, m_VertexBuffer[i]);
gl.glDrawElements(GL10.GL_TRIANGLE_FAN, vertexCount, GL10.GL_UNSIGNED_SHORT, mIndexBuffer);
}
It didn't do any work.Please tell me why. Thank you.
If you want to do FSAA, you need to create an EGL context with multisampling enabled. Write an EGLConfigChooser that returns a multisampling config (specify 1 for EGL_SAMPLE_BUFFERS), and pass it to setEGLConfigChooser.
UPDATE: Summary:
I can draw a circle using TRIANGLE_FAN and, separately, I also can draw two squares with bitmaps as textures. But the problem is when I draw the textures and then the circles. Circles aren't drawn.
I'm drawing two texturized squares (4 vertex each). Then I draw a circle using GL_TRIANGLE_FAN but it isn't being drawn correctly (see images).
When I draw the circles without the squares, it is drawn correctly.
Any ideas where could be the problem?
Please, ask for more information. Thanks
Adding some code that I think is important:
public void onSurfaceCreated(GL10 gl, EGLConfig config) {
gl.glClearColor(0.0f, 0.0f, 0.0f, 1.0f);
gl.glShadeModel(GL10.GL_SMOOTH);
gl.glFrontFace(GL10.GL_CCW);
gl.glEnable(GL10.GL_CULL_FACE);
gl.glEnable(GL10.GL_BLEND);
gl.glCullFace(GL10.GL_BACK);
gl.glBlendFunc(GL10.GL_SRC_ALPHA, GL10.GL_ONE_MINUS_SRC_ALPHA);
gl.glEnableClientState(GL10.GL_VERTEX_ARRAY);
gl.glEnable(GL10.GL_TEXTURE_2D);
}
public void onSurfaceChanged(GL10 gl, int w, int h) {
gl.glViewport(0, 0, width, height);
gl.glMatrixMode(GL10.GL_PROJECTION);
gl.glOrthof(0, w, -0, h, -1, 1);
gl.glMatrixMode(GL10.GL_MODELVIEW);
gl.glLoadIdentity();
}
public void onDrawFrame(GL10 gl) {
gl.glClear(GL10.GL_COLOR_BUFFER_BIT);
gl.glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
circle.draw(gl);
needle.draw(gl);
synchronized (tokens) {
for (Token d : tokens) {
d.draw(gl);
}
}
}
Update:
Some screenshots.
Without drawing circle and needle objects:
Drawing circle and needle:
(Look at those red lines where should be a circle)
The only change in the code between those images is commenting the lines
circle.draw(gl);
needle.draw(gl);
Token:
public void draw(GL10 gl) {
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
gl.glPushMatrix();
gl.glTranslatef(x, y, 0f);
gl.glScalef(radius, radius, 0f);
gl.glColor4f(1.0f, 0.0f, 0.0f, 1.0f);
gl.glDrawArrays(GL10.GL_TRIANGLE_FAN, 0, nVertices+2);
gl.glPopMatrix();
}
Circle and Needle:
public void draw(GL10 gl) {
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
if (shouldLoadTexture) {
loadGLTexture(gl);
shouldLoadTexture = false;
}
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
gl.glPushMatrix();
gl.glTranslatef(x, y, 0f);
gl.glRotatef((float) angle, 0f, 0f, 1f);
angle += rotAngle;
if(angle+rotAngle > 360.0)
angle -= 360.0;
gl.glScalef(width, height, 0f);
gl.glDrawElements(GL10.GL_TRIANGLES, indices.length,
GL10.GL_UNSIGNED_SHORT, indexBuffer);
gl.glPopMatrix();
}
private void loadGLTexture(GL10 gl) {
int[] textures = new int[1];
gl.glGenTextures(1, textures, 0);
textureId = textures[0];
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MIN_FILTER,
GL10.GL_LINEAR);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_MAG_FILTER,
GL10.GL_LINEAR);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_S,
GL10.GL_CLAMP_TO_EDGE);
gl.glTexParameterf(GL10.GL_TEXTURE_2D, GL10.GL_TEXTURE_WRAP_T,
GL10.GL_REPEAT);
GLUtils.texImage2D(GL10.GL_TEXTURE_2D, 0, bitmap, 0);
}
Update:
Following what Arne says in the first answer, I changed:
public void draw(GL10 gl) {
//New line
gl.glEnableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
gl.glVertexPointer(3, GL10.GL_FLOAT, 0, vertexBuffer);
if (shouldLoadTexture) {
loadGLTexture(gl);
shouldLoadTexture = false;
}
gl.glTexCoordPointer(2, GL10.GL_FLOAT, 0, textureBuffer);
gl.glBindTexture(GL10.GL_TEXTURE_2D, textureId);
gl.glPushMatrix();
gl.glTranslatef(x, y, 0f);
gl.glRotatef((float) angle, 0f, 0f, 1f);
angle += rotAngle;
if(angle+rotAngle > 360.0)
angle -= 360.0;
gl.glScalef(width, height, 0f);
gl.glDrawElements(GL10.GL_TRIANGLES, indices.length,
GL10.GL_UNSIGNED_SHORT, indexBuffer);
gl.glPopMatrix();
//New line
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);
}
Now I get no circle at all. Neither red line as in the second image.
Update:
When I don't load the texture of circle and needle (just commenting the call to loadTexture() ), I get this:
So the problem should be with the textures.
You enable texturing (by calling glEnable(GL_TEXTURE_2D)) at the beginning, but you don't provide your circles (tokens) any texture coordinates. As I suppose these shouldn't be textured, you should only enable texturing for the objects that are really textured and disable texturing again after drawing them, the same way you enable and disable the texCoord array in your updated code.
Try to disable GL_TEXTURE_COORD_ARRAY before drawing the circles with
gl.glDisableClientState(GL10.GL_TEXTURE_COORD_ARRAY);