<div dir="ltr">Hi Brian,<div> </div><div>I added glFlush and glFinish still no luck with that.</div><div>Am I doing something wrong in the shader code ?</div><div>The same code works fine with the openGL libraries using freeglut and glew.</div><div> </div><div> </div><div>Thanks & Regards,</div><div>Vikram</div></div><div class="gmail_extra"> <div class="gmail_quote">On Thu, Mar 24, 2016 at 7:15 PM, Brian Paul <<a href="mailto:brianp@vmware.com" target="_blank">brianp@vmware.com</a>> wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">On 03/24/2016 12:45 AM, vikramnrao wrote: <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> Hi, Its been quite sometime that I am looking into Off screen rendering using Mesa 11.1.2. :) I was able to render the textured model using Mesa 7.5.1 but somehow I couldn't manage lighting the scene there. However I want my code to run using Mesa 11.1.2. I am not able to see anything in the off-screen rendered targa image. It just appears blank. What is wrong in the following code ? </blockquote> [...] <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> glGetError(); // Draw the triangle ! glDrawArrays(GL_TRIANGLES, 0, indexed_vertex_data.size()); </blockquote> Try putting a glFlush() or glFinish() call here. -Brian<div class="HOEnZb"><div class="h5"> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"> SaveScreenGrab("mesa_snapshot.tga"); glDisableVertexAttribArray(vertexPosition_modelspaceID); // Cleanup VBO glDeleteBuffers(1, &vertexbuffer); glDeleteBuffers(1, &normalbuffer); glDeleteBuffers(1, &uvbuffer); glDeleteTextures(1, &diffuseMap); glDeleteProgram(programID); } ************************* Shader code ************************* -------------------- vertex shader: --------------------- attribute vec3 vertexPosition_modelspace; attribute vec2 vertexUV; attribute vec3 normalv; varying vec2 TexCoords; varying vec3 normalf; varying vec3 FragPos; uniform mat4 MVP; uniform mat4 Model; void main() { gl_Position = MVP * vec4(vertexPosition_modelspace,1); FragPos = vec3(Model * vec4(vertexPosition_modelspace,1)); normalf = vec3(Model * vec4(normalv,1)); TexCoords = vertexUV; } ------------------------ Fragment shader: ------------------------- #version 120 struct Material{ vec4 ambient; vec4 diffuse; vec4 specular; float shininess; }; struct DirLight { vec3 direction; vec3 ambient; vec3 diffuse; vec3 specular; }; in vec3 FragPos; in vec3 normalf; in vec2 TexCoords; in vec3 vertexColor; vec4 texel0; uniform sampler2D MeshTexture; uniform DirLight dirLight; out vec4 ResultFragColor; uniform vec3 viewPos; uniform Material material; uniform float matAlpha; //Function prototype vec4 SurfaceColor (in Material mat, in vec4 texel); void main() { texel0 = texture2D(MeshTexture, TexCoords); vec3 norm = normalize(normalf); vec3 viewDir = normalize(viewPos - FragPos); vec3 lightDir = normalize(-dirLight.direction); // Diffuse shading float diff = max(dot(norm, lightDir), 0.0); // Specular shading vec3 reflectDir = reflect(-lightDir, norm); float spec = pow(max(dot(viewDir, reflectDir), 0.0), material.shininess); vec4 surfaceColorValue ; surfaceColorValue = mix(material.diffuse, texel0, texel0.a); surfaceColorValue.a = min(matAlpha*( 1 + texel0.a) , 1); vec4 ambient = vec4(dirLight.ambient, 1) * surfaceColorValue ; vec4 diffuse = vec4(dirLight.diffuse, 1) * diff * surfaceColorValue ; vec4 specular = vec4(dirLight.specular, 1) * spec * material.specular ; vec4 result = ambient + diffuse + specular ; ResultFragColor = result; } vec4 SurfaceColor (in Material mat, in vec4 texel) { vec4 SurfColor; SurfColor = mix(mat.diffuse, texel, texel.a); SurfColor.a = min(matAlpha*( 1 + texel.a) , 1); return SurfColor; } } Thanks & Regards, Vikram </blockquote> </div></div></blockquote></div> </div>