Add some comments to the shaders

This commit is contained in:
Tristan Daniël Maat 2022-08-12 22:51:48 +01:00
parent 7f6cede914
commit 63e062596c
Signed by: tlater
GPG key ID: 49670FD774E43268
2 changed files with 20 additions and 7 deletions

View file

@ -1,4 +1,8 @@
#version 300 es
//FRAGMENT SHADER
//
// Basic fragment shader, just passes along colors, we don't do much
// with textures or anything else complex in this project.
precision highp float;

View file

@ -1,5 +1,10 @@
#version 300 es
//VERTEX SHADER
//
// Takes vertices of a unit cube, scales them up along Y according to
// aHeight, and colors them with basic diffuse shading.
#define CLEAR_COLOR vec4(0.0, 0.0, 0.0, 1.0)
#define BASE_COLOR vec4(1.0, 1.0, 1.0, 1.0)
#define AMBIENT_LIGHT vec3(0.3, 0.3, 0.3)
#define LIGHT_DIRECTION normalize(vec3(0.85, 0.8, 0.75))
@ -17,24 +22,28 @@ uniform mat4 uProjectionMatrix;
uniform mat4 uNormalMatrix;
void main() {
// The X position of each vertex depends on its cube's instance;
// they should align to the X axis.
float instanceX =
aVertexPosition.x + float(gl_InstanceID) * 2.0 * abs(aVertexPosition.x);
float(gl_InstanceID * 2) * abs(aVertexPosition.x) + aVertexPosition.x;
// Since we want to scale the boxes by their frequencies, make the Y
// positions of any vertices that are > 0 (1, because this is a
// cube) = the height of the frequency.
float vertexY =
aVertexPosition.y > 0.0 ? aVertexPosition.y * aHeight : aVertexPosition.y;
gl_Position = uProjectionMatrix * uModelViewMatrix *
vec4(instanceX, vertexY, aVertexPosition.zw);
vec4 transformedNormal = uNormalMatrix * vec4(aVertexNormal, 1.0);
float directionalLight =
max(dot(transformedNormal.xyz, LIGHT_DIRECTION), 0.0);
if (aHeight == 0.0) {
vColor = vec4(0.0, 0.0, 0.0, 0.0);
// Don't render cubes that don't currently have a height
// (frequency = 0)
vColor = CLEAR_COLOR;
} else {
// Properly shade and color any other cubes
vec4 transformedNormal = uNormalMatrix * vec4(aVertexNormal, 1.0);
float directionalLight =
max(dot(transformedNormal.xyz, LIGHT_DIRECTION), 0.0);
vColor = vec4(AMBIENT_LIGHT + (directionalLight * LIGHT_COLOR), 1.0);
vColor = vec4(directionalLight * LIGHT_COLOR + AMBIENT_LIGHT, 1.0);
}
}