Chief_

08-12-2013, 05:42 AM

Hello folks,

i've got the following problem:

I actually working on my bachelorthesis. My title is "Displacement Mapping with Tessellation".

I am almost finished, but i need the numbers of triangles/vertices to do some comparisons.

I am working with the JMonkey3-Engine(JME3) and OpenGL under windows. JME3 provides a statsView, the problem there is that it only gives you the number of your object you created.

For example: I create a triangle so I have 3 Vertices and 1 Triangle, now I start my programm and raise the TessellationLevel, but the counts are not increasing because the Tessellation is in the GPU.

Now there is my question, how can I get the numbers?

Here are my Shader Stages (a simple one, without DisplacemetMapping):

//vertex-shader

uniform mat4 g_WorldMatrix;

in vec3 inPosition;

out vec3 vPosition;

void main() {

vec4 position = g_WorldMatrix * vec4(inPosition, 1.0);

position /= position.w;

vPosition = position.xyz;

}

//TC

layout(vertices = 3) out;

in vec3 vPosition[];

out vec3 tcPosition[];

uniform float m_InnerTess;

uniform float m_OuterTess;

void main()

{

tcPosition[gl_InvocationID] = vPosition[gl_InvocationID];

if (gl_InvocationID == 0) {

gl_TessLevelInner[0] = m_InnerTess;

gl_TessLevelOuter[0] = m_OuterTess;

gl_TessLevelOuter[1] = m_OuterTess;

gl_TessLevelOuter[2] = m_OuterTess;

}

}

//TES

layout(triangles, equal_spacing, ccw) in;

in vec3 tcPosition[];

out vec3 tePosition;

uniform mat4 g_ViewProjectionMatrix;

vec3 interpolate3D(vec3 v0, vec3 v1, vec3 v2)

{

return vec3(gl_TessCoord.x) * v0 + vec3(gl_TessCoord.y) * v1 + vec3(gl_TessCoord.z) * v2;

}

void main()

{

tePosition = interpolate3D(tcPosition[0], tcPosition[1], tcPosition[2]);

gl_Position = g_ViewProjectionMatrix * vec4(tePosition, 1.0);

}

//FS

out vec4 outFragColor;

void main() {

vec4 color = vec4(1.0);

outFragColor = color;

}

That is my code for a single triangle to tessellate, by giving him the number of the tessellationlevel.

I guess i have to look at the TES because he gives me the vertices to draw.

If you have any more question, feel free to ask, I hope you guys can help me.

i've got the following problem:

I actually working on my bachelorthesis. My title is "Displacement Mapping with Tessellation".

I am almost finished, but i need the numbers of triangles/vertices to do some comparisons.

I am working with the JMonkey3-Engine(JME3) and OpenGL under windows. JME3 provides a statsView, the problem there is that it only gives you the number of your object you created.

For example: I create a triangle so I have 3 Vertices and 1 Triangle, now I start my programm and raise the TessellationLevel, but the counts are not increasing because the Tessellation is in the GPU.

Now there is my question, how can I get the numbers?

Here are my Shader Stages (a simple one, without DisplacemetMapping):

//vertex-shader

uniform mat4 g_WorldMatrix;

in vec3 inPosition;

out vec3 vPosition;

void main() {

vec4 position = g_WorldMatrix * vec4(inPosition, 1.0);

position /= position.w;

vPosition = position.xyz;

}

//TC

layout(vertices = 3) out;

in vec3 vPosition[];

out vec3 tcPosition[];

uniform float m_InnerTess;

uniform float m_OuterTess;

void main()

{

tcPosition[gl_InvocationID] = vPosition[gl_InvocationID];

if (gl_InvocationID == 0) {

gl_TessLevelInner[0] = m_InnerTess;

gl_TessLevelOuter[0] = m_OuterTess;

gl_TessLevelOuter[1] = m_OuterTess;

gl_TessLevelOuter[2] = m_OuterTess;

}

}

//TES

layout(triangles, equal_spacing, ccw) in;

in vec3 tcPosition[];

out vec3 tePosition;

uniform mat4 g_ViewProjectionMatrix;

vec3 interpolate3D(vec3 v0, vec3 v1, vec3 v2)

{

return vec3(gl_TessCoord.x) * v0 + vec3(gl_TessCoord.y) * v1 + vec3(gl_TessCoord.z) * v2;

}

void main()

{

tePosition = interpolate3D(tcPosition[0], tcPosition[1], tcPosition[2]);

gl_Position = g_ViewProjectionMatrix * vec4(tePosition, 1.0);

}

//FS

out vec4 outFragColor;

void main() {

vec4 color = vec4(1.0);

outFragColor = color;

}

That is my code for a single triangle to tessellate, by giving him the number of the tessellationlevel.

I guess i have to look at the TES because he gives me the vertices to draw.

If you have any more question, feel free to ask, I hope you guys can help me.