So today I'm trying to port that one to ZGE: https://stackoverflow.com/questions/816 ... ngl-es-2-0
Since I'm not using textures, I was trying to do that directly with the vertex colors. But the only thing I can get is to make the colors more white with the u_glowIntensity. It doesn't glow outside the mesh. Is that a restriction due to me not using a texture, or is there something else that I don't understand in the logic?
Code: Select all
<?xml version="1.0" encoding="iso-8859-1" ?>
<ZApplication Name="App" Caption="ZGameEditor application" GLBase="1" FileVersion="2">
<OnLoaded>
<SpawnModel Model="ModelCube"/>
</OnLoaded>
<Content>
<Model Name="ModelCube" Rotation="0 0.01 0" RotationVelocity="0.02 0.01 0">
<OnRender>
<UseMaterial Material="MaterialGlow"/>
<RenderMesh Mesh="MeshCube"/>
</OnRender>
</Model>
<Mesh Name="MeshCube">
<Producers>
<MeshBox/>
<MeshExpression VertexColors="255">
<Expression>
<![CDATA[
C.R = rnd();
C.G = rnd();
C.B = rnd();]]>
</Expression>
</MeshExpression>
</Producers>
</Mesh>
<Material Name="MaterialGlow" Shader="ShaderGlow"/>
<Shader Name="ShaderGlow">
<VertexShaderSource>
<![CDATA[#ifdef GL_ES
#ifdef GL_FRAGMENT_PRECISION_HIGH
precision highp float;
#else
precision mediump float;
#endif
#endif
uniform mat4 modelViewMatrix;
uniform mat4 modelViewProjectionMatrix;
uniform mat3 normalMatrix;
attribute vec4 position, color; // vertex position & color
attribute vec3 normal; // vertex normal
varying vec3 N;
varying vec3 v_position; // View-space position to pass to the fragment shader
varying vec4 v_color;
void main(void)
{
// Calculate view-space position
v_position = vec3(modelViewMatrix * position);
// Calculate view-space normal
N = normalize(normalMatrix * normal);
// Pass vertex color to fragment shader
v_color = color;
// Calculate position of the vertex in clip space
gl_Position = modelViewProjectionMatrix * position;
}]]>
</VertexShaderSource>
<FragmentShaderSource>
<![CDATA[#ifdef GL_ES
precision mediump float;
#endif
varying vec4 v_color; // Vertex color from the vertex shader
varying vec3 v_position; // View-space position to pass to the fragment shader
//uniform vec2 u_resolution; // Resolution of the screen
//uniform float u_glowIntensity; // Glow intensity
//uniform float u_sigma; // Sigma value for Gaussian blur
//uniform int u_width; // Width value for Gaussian blur
const vec2 u_resolution = vec2(800.0, 600.0);
const float u_glowIntensity = 0.5; // 0 = no color variation, 1 = white
const float u_sigma = 1.0; // Adjust the sigma value for Gaussian blur
const int u_width = 5; // Adjust the width for Gaussian blur
// Function to apply Gaussian blur for glow effect
vec4 gaussianBlur(vec2 coord) {
vec4 blurColor = vec4(0.0);
float weightSum = 0.0;
vec2 texSize = u_resolution; // Texture size based on screen resolution
// Sample around the current coordinate
for (int i = -u_width; i <= u_width; i++) {
for (int j = -u_width; j <= u_width; j++) {
vec2 offset = vec2(i, j) / texSize;
float distance = length(offset);
float weight = exp(-distance * distance / (2.0 * u_sigma * u_sigma));
// Sample the color from the offset position and apply the weight
vec2 sampleCoord = coord + offset;
blurColor += v_color * weight;
weightSum += weight;
}
}
// Normalize the blur color
return blurColor / weightSum;
}
void main() {
// Calculate the screen coordinates
vec2 screenCoord = gl_FragCoord.xy / u_resolution;
// Apply Gaussian blur
vec4 glowColor = gaussianBlur(screenCoord);
// Combine the vertex color and the glow effect
gl_FragColor = v_color + glowColor * u_glowIntensity;
// For debug
//gl_FragColor = v_color;
}]]>
</FragmentShaderSource>
</Shader>
</Content>
</ZApplication>
