	[x] Posted via EE Mobile
	Search, ask, and monitor your questions on the go with EE Mobile. Visit Experts Exchange from your mobile device and never be out of touch again.

Question

	[x] Attachment Details

[x]

The Solution Rating System

With so many solutions, how can you tell which solutions are most likely to help you and which ones are not? To provide you with a tool to use, we rate our solutions based on various elements that most accurately determine if a solution is a quality solution. To explain what factors affect the solution rating, here are the elements we take into consideration when formulating our solution rating.

The Grade of the Solution
The Zone Rank of the Expert Providing the Solution
The Number of Author and Expert Comments
The Number of Experts Contributing
The Feedback of the Community

Your Input Matters
Because of the way the system is set up, the most important variable in this equation is you. As a member of Experts Exchange, you are able to cast your vote on the quality of the solutions in regard to how complete, accurate, helpful and easy to understand each solution is. When you provide your feedback, each rating is adjusted accordingly. So, if you see a solution that has a poor rating that you think is a good solution, let us know by rating it. As you do, the rating will be adjusted and will become more accurate for other members of our site.

If you have any suggestions that you would like to make for our rating system, please ask a question in the Suggestions Zone of Community Support.

Thank you!

6.8

cannot render texture to framebuffer (blank screen)

Asked by collages in OpenGL Graphics & Game Programming, 3D Game Programming

Tags: fbo, framebuffer, opengl, texture

I have read numerous articles/tutorials online regarding drawing a texture to a framebuffer in opengl, but I am having no luck getting it to work. I am creating a framebuffer, drawing a texture to the fbo, and then drawing the fbo texture to the screen but nothing displays. I am at a loss. If i comment out the fbo code and draw the embedded texture directly to the screen, that works. I am using OpenGL ES 1.1

View the Solution FREE for 30 Days

         
           
             1:
2:
3:
4:
5:
6:
7:
8:
9:
10:
11:
12:
13:
14:
15:
16:
17:
18:
19:
20:
21:
22:
23:
24:
25:
26:
27:
28:
29:
30:
31:
32:
33:
34:
35:
36:
37:
38:
39:
40:
41:
42:
43:
44:
45:
46:
47:
48:
49:
50:
51:
52:
53:
54:
55:
56:
57:
58:
59:
60:
61:
62:
63:
64:
65:
66:
67:
68:
69:
70:
71:
72:
73:
74:
75:
76:
77:
78:
79:

           
           
             // INITIALIZATION
	glEnable(GL_TEXTURE_2D);
	glEnable(GL_BLEND);
	glBlendFunc(GL_ONE, GL_ONE_MINUS_SRC_ALPHA);
	
	// Load Test Texture
	glGenTextures(1, &textureTest);
	glBindTexture(GL_TEXTURE_2D, textureTest);			// Bind Our Texture
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);	// Linear Filtered
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);	// Linear Filtered
	[self loadTexture: @"texture"]; // calls glTexImage2D with image data from png
	
	glMatrixMode(GL_PROJECTION);
	glLoadIdentity();
	glViewport(0,0, 320.0f,480.0f);
	glOrthof(0,320.0f, 480.0f,0, -1.0f, 1.0f); // left, right, bottom, top
	glMatrixMode(GL_MODELVIEW);
	
	//FBO Setup
	glGenTextures(1, &textureFBO); // texture handle
	glBindTexture(GL_TEXTURE_2D, textureFBO); //bind it.
	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, 512, 512, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL); 
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);	// Linear Filtered
	glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);	// Linear Filtered
	
	glGenFramebuffersOES(1, &FBO); // frame buffer 
	glBindFramebufferOES(GL_FRAMEBUFFER_OES, FBO); //bind the frame buffer
	
	// attach texture to framebuffer color buffer
	glFramebufferTexture2DOES(GL_FRAMEBUFFER_OES, GL_COLOR_ATTACHMENT0_OES, GL_TEXTURE_2D, textureFBO, 0);
	if(glCheckFramebufferStatusOES(GL_FRAMEBUFFER_OES) != GL_FRAMEBUFFER_COMPLETE_OES)  printf("CANNOT CREATE FRAMEBUFFER\n");
 
 
// MAIN DRAWING LOOP
	static const Vertex3D vertices[] = {
        {0.0,  100.0, 0.0},
        { 100.0,  100.0, 0.0},
        { 0.0, 200.0, 0.0},
        { 100.0, 200.0, 0.0}
    };
	static const GLfloat texCoords[] = {
        0.0, 1.0,
        1.0, 1.0,
        0.0, 0.0,
        1.0, 0.0
    };
	
	glClear(GL_COLOR_BUFFER_BIT);
	glLoadIdentity();
	
	// Render to texture
	glBindFramebufferOES(GL_FRAMEBUFFER_OES, FBO);
	
	// Draw test texture
	glBindTexture(GL_TEXTURE_2D, textureTest);
	glEnableClientState(GL_VERTEX_ARRAY);
	glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glVertexPointer(3, GL_FLOAT, 0, vertices);
	glTexCoordPointer(2, GL_FLOAT, 0, texCoords);
    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
	glDisableClientState(GL_VERTEX_ARRAY);
	glDisableClientState(GL_TEXTURE_COORD_ARRAY);
	glBindTexture(GL_TEXTURE_2D, 0); //disable any bound textures.
	// End draw test texture
	
	// Render to screen
	glBindFramebufferOES(GL_FRAMEBUFFER_OES, 0); 
	
	// Draw FBO texture
	glBindTexture(GL_TEXTURE_2D, textureFBO);
	glEnableClientState(GL_VERTEX_ARRAY);
	glEnableClientState(GL_TEXTURE_COORD_ARRAY);
    glVertexPointer(3, GL_FLOAT, 0, vertices);
	glTexCoordPointer(2, GL_FLOAT, 0, texCoords);
    glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
	glDisableClientState(GL_VERTEX_ARRAY);
	glDisableClientState(GL_TEXTURE_COORD_ARRAY);
	glBindTexture(GL_TEXTURE_2D, 0); //disable any bound textures.
	// End draw FBO texture

           
         

20091111-EE-VQP-92 - Hierarchy / EE_QW_3_20080625

Hall of Fame

1. ikework72,039
2. StormSeed6,450
3. Infinity084,972
4. abel4,000
4. jkr4,000
6. Interactive...2,600
7. richardpal...2,320
8. Callandor2,000
8. Jason2102,000
8. carl_tawn2,000
8. simonlai2,000
8. jgordos2,000
8. 2PiFL2,000
8. knoxzoo2,000
8. mrjoltcola2,000
8. bham3dman2,000
8. darkphotn2,000
8. Chimeraza2,000
19. JoseParrot1,752
20. hybridart1,500
20. tigin441,500
20. AnthonyR...1,500
20. Wouter_1,500
24. manojkum...1,400
25. evilrix1,268

1. ikework160,124
2. davebytes61,456
3. Infinity0842,492
4. JoseParrot27,350
5. Interactive...23,472
6. ozo18,840
7. NovaDeni...17,114
8. jgordos16,830
9. dbkruger15,784
10. sunnycoder14,020
11. SWortham7,360
12. itsmeandn...7,250
13. trinitrotolu...7,200
14. jkr7,000
15. StormSeed6,950
16. thegilb6,500
17. davidnsc16,050
18. evilrix5,768
19. _corey_5,220
20. fridom5,000
20. shirsoft5,000
22. MASQUE...4,350
23. TimYates4,300
24. DalTXColt...4,160
25. abel4,000

cannot render texture to framebuffer (blank screen)

Asked by collages in OpenGL Graphics & Game Programming, 3D Game Programming

Tags: fbo, framebuffer, opengl, texture

About this solution