virtualx-engine/drivers/gles2/shaders/cube_to_dp.glsl
Rémi Verschelde 57416bfbce GLES2: Define 'lowp' for OpenGL 2.1
Precision qualifiers are only used on OpenGL ES 2.0 and 3.0,
and while OpenGL 3.3 defines them for compatibility (but without
practical effect), they're missing from OpenGL 2.1, so we define
them to prevent compilation errors.

Fixes #24521.
2018-12-21 15:14:58 +01:00

97 lines
2.2 KiB
GLSL

/* clang-format off */
[vertex]
#ifdef USE_GLES_OVER_GL
#define lowp
#define mediump
#define highp
#else
precision mediump float;
precision mediump int;
#endif
attribute highp vec4 vertex_attrib; // attrib:0
/* clang-format on */
attribute vec2 uv_in; // attrib:4
varying vec2 uv_interp;
void main() {
uv_interp = uv_in;
gl_Position = vertex_attrib;
}
/* clang-format off */
[fragment]
#ifdef USE_GLES_OVER_GL
#define lowp
#define mediump
#define highp
#else
precision mediump float;
precision mediump int;
#endif
uniform highp samplerCube source_cube; //texunit:0
/* clang-format on */
varying vec2 uv_interp;
uniform bool z_flip;
uniform highp float z_far;
uniform highp float z_near;
uniform highp float bias;
void main() {
highp vec3 normal = vec3(uv_interp * 2.0 - 1.0, 0.0);
/*
if (z_flip) {
normal.z = 0.5 - 0.5 * ((normal.x * normal.x) + (normal.y * normal.y));
} else {
normal.z = -0.5 + 0.5 * ((normal.x * normal.x) + (normal.y * normal.y));
}
*/
//normal.z = sqrt(1.0 - dot(normal.xy, normal.xy));
//normal.xy *= 1.0 + normal.z;
normal.z = 0.5 - 0.5 * ((normal.x * normal.x) + (normal.y * normal.y));
normal = normalize(normal);
/*
normal.z = 0.5;
normal = normalize(normal);
*/
if (!z_flip) {
normal.z = -normal.z;
}
//normal = normalize(vec3( uv_interp * 2.0 - 1.0, 1.0 ));
float depth = textureCube(source_cube, normal).r;
// absolute values for direction cosines, bigger value equals closer to basis axis
vec3 unorm = abs(normal);
if ((unorm.x >= unorm.y) && (unorm.x >= unorm.z)) {
// x code
unorm = normal.x > 0.0 ? vec3(1.0, 0.0, 0.0) : vec3(-1.0, 0.0, 0.0);
} else if ((unorm.y > unorm.x) && (unorm.y >= unorm.z)) {
// y code
unorm = normal.y > 0.0 ? vec3(0.0, 1.0, 0.0) : vec3(0.0, -1.0, 0.0);
} else if ((unorm.z > unorm.x) && (unorm.z > unorm.y)) {
// z code
unorm = normal.z > 0.0 ? vec3(0.0, 0.0, 1.0) : vec3(0.0, 0.0, -1.0);
} else {
// oh-no we messed up code
// has to be
unorm = vec3(1.0, 0.0, 0.0);
}
float depth_fix = 1.0 / dot(normal, unorm);
depth = 2.0 * depth - 1.0;
float linear_depth = 2.0 * z_near * z_far / (z_far + z_near - depth * (z_far - z_near));
gl_FragDepth = (linear_depth * depth_fix + bias) / z_far;
}