From 9d334f3cf3ce30f1fc7159b458707bdf3e8080f6 Mon Sep 17 00:00:00 2001 From: Jannik Vogel Date: Wed, 6 Apr 2016 03:14:13 +0200 Subject: [PATCH] Rasterizer: Use Fix12P4 (rasterizer coordinates) and make it signed --- src/video_core/rasterizer.cpp | 90 ++++++++++++++++++++++++++--------- 1 file changed, 67 insertions(+), 23 deletions(-) diff --git a/src/video_core/rasterizer.cpp b/src/video_core/rasterizer.cpp index 65168f05a..0fae3166b 100644 --- a/src/video_core/rasterizer.cpp +++ b/src/video_core/rasterizer.cpp @@ -260,21 +260,60 @@ static u8 PerformStencilAction(Regs::StencilAction action, u8 old_stencil, u8 re // NOTE: Assuming that rasterizer coordinates are 12.4 fixed-point values struct Fix12P4 { Fix12P4() {} - Fix12P4(u16 val) : val(val) {} + + static Fix12P4 FromRaw(s16 val) { + Fix12P4 res; + res.val = val; + return res; + } + + static Fix12P4 FromInt(s16 intVal, u16 fracVal = 0) { + return FromRaw(static_cast(((intVal * 16) & IntMask()) | (fracVal & FracMask()))); + } + + static Fix12P4 FromFloat(float fltVal) { + return FromRaw(static_cast(round(fltVal * 16.0f))); + } + + static Fix12P4 Zero() { + return FromRaw(0); + } static u16 FracMask() { return 0xF; } static u16 IntMask() { return (u16)~0xF; } - operator u16() const { + s16 Int() const { + return static_cast((val & IntMask()) / 16); + } + + u16 Frac() const { + return static_cast(val & FracMask()); + } + + operator s16() const { return val; } bool operator < (const Fix12P4& oth) const { - return (u16)*this < (u16)oth; + return (s16)*this < (s16)oth; } + Fix12P4 operator + (const Fix12P4& oth) const { + return FromRaw(val + oth.val); + } + + Fix12P4 operator / (const Fix12P4& oth) const { + return FromRaw(static_cast((int)val * 16 / (int)oth.val)); + } + + Fix12P4& operator += (const Fix12P4& oth) { + val += oth.val; + return *this; + } + + private: - u16 val; + s16 val; }; /** @@ -308,9 +347,9 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, // vertex positions in rasterizer coordinates static auto FloatToFix = [](float24 flt) { - // TODO: Rounding here is necessary to prevent garbage pixels at + // TODO: Rounding in Fix12P4::FromFloat is necessary to prevent garbage pixels at // triangle borders. Is it that the correct solution, though? - return Fix12P4(static_cast(round(flt.ToFloat32() * 16.0f))); + return Fix12P4::FromFloat(flt.ToFloat32()); }; static auto ScreenToRasterizerCoordinates = [](const Math::Vec3& vec) { return Math::Vec3{FloatToFix(vec.x), FloatToFix(vec.y), FloatToFix(vec.z)}; @@ -338,16 +377,19 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, return; } - // TODO: Proper scissor rect test! - u16 min_x = std::min({vtxpos[0].x, vtxpos[1].x, vtxpos[2].x}); - u16 min_y = std::min({vtxpos[0].y, vtxpos[1].y, vtxpos[2].y}); - u16 max_x = std::max({vtxpos[0].x, vtxpos[1].x, vtxpos[2].x}); - u16 max_y = std::max({vtxpos[0].y, vtxpos[1].y, vtxpos[2].y}); + // Get bounding box for triangle + Fix12P4 min_x = std::min({vtxpos[0].x, vtxpos[1].x, vtxpos[2].x}); + Fix12P4 min_y = std::min({vtxpos[0].y, vtxpos[1].y, vtxpos[2].y}); + Fix12P4 max_x = std::max({vtxpos[0].x, vtxpos[1].x, vtxpos[2].x}); + Fix12P4 max_y = std::max({vtxpos[0].y, vtxpos[1].y, vtxpos[2].y}); - min_x &= Fix12P4::IntMask(); - min_y &= Fix12P4::IntMask(); - max_x = ((max_x + Fix12P4::FracMask()) & Fix12P4::IntMask()); - max_y = ((max_y + Fix12P4::FracMask()) & Fix12P4::IntMask()); + // TODO: Proper scissor rect test! + + Fix12P4 frac = Fix12P4::FromInt(0, Fix12P4::FracMask()); + min_x = Fix12P4::FromInt(min_x.Int(), 0); + min_y = Fix12P4::FromInt(min_y.Int(), 0); + max_x = Fix12P4::FromInt((max_x + frac).Int()); + max_y = Fix12P4::FromInt((max_y + frac).Int()); // Triangle filling rules: Pixels on the right-sided edge or on flat bottom edges are not // drawn. Pixels on any other triangle border are drawn. This is implemented with three bias @@ -380,8 +422,10 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, // Enter rasterization loop, starting at the center of the topleft bounding box corner. // TODO: Not sure if looping through x first might be faster - for (u16 y = min_y + 8; y < max_y; y += 0x10) { - for (u16 x = min_x + 8; x < max_x; x += 0x10) { + Fix12P4 pixel = Fix12P4::FromInt(1); + Fix12P4 half_pixel = pixel / Fix12P4::FromInt(2); + for (Fix12P4 y = min_y + half_pixel; y < max_y; y += pixel) { + for (Fix12P4 x = min_x + half_pixel; x < max_x; x += pixel) { // Calculate the barycentric coordinates w0, w1 and w2 int w0 = bias0 + SignedArea(vtxpos[1].xy(), vtxpos[2].xy(), {x, y}); @@ -838,11 +882,11 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, auto UpdateStencil = [stencil_test, x, y, &old_stencil](Pica::Regs::StencilAction action) { u8 new_stencil = PerformStencilAction(action, old_stencil, stencil_test.reference_value); if (g_state.regs.framebuffer.allow_depth_stencil_write != 0) - SetStencil(x >> 4, y >> 4, (new_stencil & stencil_test.write_mask) | (old_stencil & ~stencil_test.write_mask)); + SetStencil(x.Int(), y.Int(), (new_stencil & stencil_test.write_mask) | (old_stencil & ~stencil_test.write_mask)); }; if (stencil_action_enable) { - old_stencil = GetStencil(x >> 4, y >> 4); + old_stencil = GetStencil(x.Int(), y.Int()); u8 dest = old_stencil & stencil_test.input_mask; u8 ref = stencil_test.reference_value & stencil_test.input_mask; @@ -913,7 +957,7 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, u32 z = (u32)(depth * ((1 << num_bits) - 1)); if (output_merger.depth_test_enable) { - u32 ref_z = GetDepth(x >> 4, y >> 4); + u32 ref_z = GetDepth(x.Int(), y.Int()); bool pass = false; @@ -959,13 +1003,13 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, } if (regs.framebuffer.allow_depth_stencil_write != 0 && output_merger.depth_write_enable) - SetDepth(x >> 4, y >> 4, z); + SetDepth(x.Int(), y.Int(), z); // The stencil depth_pass action is executed even if depth testing is disabled if (stencil_action_enable) UpdateStencil(stencil_test.action_depth_pass); - auto dest = GetPixel(x >> 4, y >> 4); + auto dest = GetPixel(x.Int(), y.Int()); Math::Vec4 blend_output = combiner_output; if (output_merger.alphablend_enable) { @@ -1168,7 +1212,7 @@ static void ProcessTriangleInternal(const Shader::OutputVertex& v0, }; if (regs.framebuffer.allow_color_write != 0) - DrawPixel(x >> 4, y >> 4, result); + DrawPixel(x.Int(), y.Int(), result); } } }