| static const char *demo_shader_hlsl = |
| "/*\n" |
| " * Copyright 2026 Behdad Esfahbod. All Rights Reserved.\n" |
| " */\n" |
| "\n" |
| "cbuffer Uniforms : register(b0) {\n" |
| " float4x4 mvp;\n" |
| " float2 viewport;\n" |
| " float gamma;\n" |
| " float stem_darkening;\n" |
| " float4 foreground;\n" |
| " float debug;\n" |
| " float3 _pad;\n" |
| "};\n" |
| "\n" |
| "struct VSInput {\n" |
| " float2 position : POSITION;\n" |
| " float2 texcoord : TEXCOORD0;\n" |
| " float2 normal : NORMAL;\n" |
| " float emPerPos : TEXCOORD1;\n" |
| " uint glyphLoc : TEXCOORD2;\n" |
| "};\n" |
| "\n" |
| "struct PSInput {\n" |
| " float4 pos : SV_Position;\n" |
| " float2 texcoord : TEXCOORD0;\n" |
| " nointerpolation uint glyphLoc : TEXCOORD1;\n" |
| "};\n" |
| "\n" |
| "PSInput vs_main (VSInput input) {\n" |
| " float2 pos = input.position;\n" |
| " float2 tex = input.texcoord;\n" |
| " float4 jac = float4 (input.emPerPos, 0.0, 0.0, -input.emPerPos);\n" |
| " hb_gpu_dilate (pos, tex, input.normal, jac, mvp, viewport);\n" |
| " PSInput output;\n" |
| " output.pos = mul (mvp, float4 (pos, 0.0, 1.0));\n" |
| " output.texcoord = tex;\n" |
| " output.glyphLoc = input.glyphLoc;\n" |
| " return output;\n" |
| "}\n" |
| "\n" |
| "float4 ps_main (PSInput input) : SV_Target {\n" |
| "#ifdef HB_GPU_DEMO_DRAW\n" |
| " float cov = hb_gpu_draw (input.texcoord, input.glyphLoc);\n" |
| " float4 c = float4 (foreground.rgb * foreground.a, foreground.a) * cov;\n" |
| "#else\n" |
| " float4 c = hb_gpu_paint (input.texcoord, input.glyphLoc, foreground);\n" |
| "#endif\n" |
| "\n" |
| " if (stem_darkening > 0.0 && c.a > 0.0) {\n" |
| " float2 fw = fwidth (input.texcoord);\n" |
| " float ppem = 1.0 / max (fw.x, fw.y);\n" |
| " float brightness = dot (c.rgb, float3 (1.0/3.0, 1.0/3.0, 1.0/3.0)) / c.a;\n" |
| " float darkened = hb_gpu_stem_darken (c.a, brightness, ppem);\n" |
| " c *= darkened / c.a;\n" |
| " }\n" |
| "\n" |
| " if (gamma != 1.0)\n" |
| " c.a = pow (c.a, gamma);\n" |
| " return c;\n" |
| "}\n" |
| ; |
