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Diffstat (limited to 'src/osd/modules/opengl/shader/glsl_bilinear_idx16_lut.fsh.c')
-rw-r--r--src/osd/modules/opengl/shader/glsl_bilinear_idx16_lut.fsh.c57
1 files changed, 57 insertions, 0 deletions
diff --git a/src/osd/modules/opengl/shader/glsl_bilinear_idx16_lut.fsh.c b/src/osd/modules/opengl/shader/glsl_bilinear_idx16_lut.fsh.c
new file mode 100644
index 00000000000..62844692cbe
--- /dev/null
+++ b/src/osd/modules/opengl/shader/glsl_bilinear_idx16_lut.fsh.c
@@ -0,0 +1,57 @@
+const char glsl_bilinear_idx16_lut_fsh_src[] =
+"\n"
+"#pragma optimize (on)\n"
+"#pragma debug (off)\n"
+"\n"
+"uniform sampler2D color_texture;\n"
+"uniform sampler2D colortable_texture;\n"
+"uniform vec2 colortable_sz; // ct size\n"
+"uniform vec2 colortable_pow2_sz; // pow2 ct size\n"
+"uniform vec2 color_texture_pow2_sz; // pow2 tex size\n"
+"\n"
+"vec4 lutTex2D(in vec2 texcoord)\n"
+"{\n"
+" vec4 color_tex;\n"
+" vec2 color_map_coord;\n"
+"\n"
+" // normalized texture coordinates ..\n"
+" color_tex = texture2D(color_texture, texcoord);\n"
+"\n"
+" // GL_UNSIGNED_SHORT GL_ALPHA in ALPHA16 conversion:\n"
+" // general: f = c / ((2*N)-1), c color bitfield, N number of bits\n"
+" // ushort: c = ((2**16)-1)*f;\n"
+" color_map_coord.x = floor( 65535.0 * color_tex.a + 0.5 );\n"
+"\n"
+" // map it to the 2D lut table\n"
+" color_map_coord.y = floor(color_map_coord.x/colortable_sz.x);\n"
+" color_map_coord.x = mod(color_map_coord.x,colortable_sz.x);\n"
+"\n"
+" return texture2D(colortable_texture, (color_map_coord+vec2(0.5)) / colortable_pow2_sz);\n"
+"}\n"
+"\n"
+"void main()\n"
+"{\n"
+" vec2 xy = gl_TexCoord[0].st;\n"
+"\n"
+" // mix(x,y,a): x*(1-a) + y*a\n"
+" //\n"
+" // bilinear filtering includes 2 mix:\n"
+" //\n"
+" // pix1 = tex[x0][y0] * ( 1 - u_ratio ) + tex[x1][y0] * u_ratio\n"
+" // pix2 = tex[x0][y1] * ( 1 - u_ratio ) + tex[x1][y1] * u_ratio\n"
+" // fin = pix1 * ( 1 - v_ratio ) + pix2 * v_ratio\n"
+" //\n"
+" // so we can use the build in mix function for these 2 computations ;-)\n"
+" //\n"
+" vec2 uv_ratio = fract(xy*color_texture_pow2_sz); // xy*color_texture_pow2_sz - floor(xy*color_texture_pow2_sz);\n"
+" vec2 one = 1.0/color_texture_pow2_sz;\n"
+"\n"
+" vec4 col1, col2;\n"
+"\n"
+" col1 = mix( lutTex2D(xy ), lutTex2D(xy + vec2(one.x, 0.0)), uv_ratio.x);\n"
+" col2 = mix( lutTex2D(xy + vec2(0.0, one.y)), lutTex2D(xy + one ), uv_ratio.x);\n"
+"\n"
+" gl_FragColor = mix ( col1, col2, uv_ratio.y );\n"
+"}\n"
+"\n"
+;