// Copyright (c) 2012- PPSSPP Project. // This program is free software: you can redistribute it and/or modify // it under the terms of the GNU General Public License as published by // the Free Software Foundation, version 2.0 or later versions. // This program is distributed in the hope that it will be useful, // but WITHOUT ANY WARRANTY; without even the implied warranty of // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the // GNU General Public License 2.0 for more details. // A copy of the GPL 2.0 should have been included with the program. // If not, see http://www.gnu.org/licenses/ // Official git repository and contact information can be found at // https://github.com/hrydgard/ppsspp and http://www.ppsspp.org/. #if defined(USING_GLES2) #define GLSL_ES_1_0 #else #define GLSL_1_3 // SDL 1.2 on Apple does not have support for OpenGL 3 and hence needs // special treatment in the shader generator. #if defined(__APPLE__) #define FORCE_OPENGL_2_0 #endif #endif #include "FragmentShaderGenerator.h" #include "../ge_constants.h" #include "../GPUState.h" #include #define WRITE p+=sprintf // #define DEBUG_SHADER // GL_NV_shader_framebuffer_fetch looks interesting.... static bool IsAlphaTestTriviallyTrue() { int alphaTestFunc = gstate.alphatest & 7; int alphaTestRef = (gstate.alphatest >> 8) & 0xFF; switch (alphaTestFunc) { case GE_COMP_ALWAYS: return true; case GE_COMP_GEQUAL: if (alphaTestRef == 0) return true; case GE_COMP_LEQUAL: if (alphaTestRef == 255) return true; default: return false; } } // Here we must take all the bits of the gstate that determine what the fragment shader will // look like, and concatenate them together into an ID. void ComputeFragmentShaderID(FragmentShaderID *id) { memset(&id->d[0], 0, sizeof(id->d)); bool enableFog = gstate.isFogEnabled() && !gstate.isModeThrough() && !gstate.isModeClear(); int lmode = (gstate.lmode & 1) && (gstate.lightingEnable & 1); if (gstate.clearmode & 1) { // We only need one clear shader, so let's ignore the rest of the bits. id->d[0] = 1; } else { bool enableAlphaTest = (gstate.alphaTestEnable & 1) && !IsAlphaTestTriviallyTrue(); bool enableColorTest = (gstate.colorTestEnable & 1); // id->d[0] |= (gstate.clearmode & 1); if (gstate.textureMapEnable & 1) { id->d[0] |= 1 << 1; id->d[0] |= (gstate.texfunc & 0x7) << 2; id->d[0] |= ((gstate.texfunc & 0x100) >> 8) << 5; // rgb or rgba id->d[0] |= ((gstate.texfunc & 0x10000) >> 16) << 6; // color double } id->d[0] |= (lmode & 1) << 7; id->d[0] |= (gstate.alphaTestEnable & 1) << 8; if (enableAlphaTest) id->d[0] |= (gstate.alphatest & 0x7) << 9; // alpha test func id->d[0] |= (gstate.colorTestEnable & 1) << 12; if (enableColorTest) id->d[0] |= (gstate.colortest & 0x3) << 13; // color test func id->d[0] |= (enableFog & 1) << 15; } } // Missing: Alpha test, color test, Z depth range, fog // Also, logic ops etc, of course. Urgh. // We could do all this with booleans, but I don't trust the shader compilers on // Android devices to be anything but stupid. void GenerateFragmentShader(char *buffer) { char *p = buffer; #if defined(GLSL_ES_1_0) WRITE(p, "precision lowp float;\n"); #elif !defined(FORCE_OPENGL_2_0) WRITE(p, "#version 110\n"); #endif int lmode = (gstate.lmode & 1) && (gstate.lightingEnable & 1); int doTexture = (gstate.textureMapEnable & 1) && !(gstate.clearmode & 1); bool enableFog = gstate.isFogEnabled() && !gstate.isModeThrough() && !gstate.isModeClear(); bool enableAlphaTest = (gstate.alphaTestEnable & 1) && !gstate.isModeClear() && !IsAlphaTestTriviallyTrue(); bool enableColorTest = (gstate.colorTestEnable & 1) && !gstate.isModeClear(); bool enableColorDoubling = (gstate.texfunc & 0x10000) != 0; if (doTexture) WRITE(p, "uniform sampler2D tex;\n"); if (enableAlphaTest || enableColorTest) { WRITE(p, "uniform vec4 u_alphacolorref;\n"); WRITE(p, "uniform vec4 u_colormask;\n"); } if (gstate.textureMapEnable & 1) { WRITE(p, "uniform vec3 u_texenv;\n"); } WRITE(p, "varying vec4 v_color0;\n"); if (lmode) WRITE(p, "varying vec3 v_color1;\n"); if (enableFog) { WRITE(p, "uniform vec3 u_fogcolor;\n"); #if defined(GLSL_ES_1_0) WRITE(p, "varying mediump float v_fogdepth;\n"); #else WRITE(p, "varying float v_fogdepth;\n"); #endif } if (doTexture) WRITE(p, "varying vec2 v_texcoord;\n"); WRITE(p, "void main() {\n"); if (gstate.clearmode & 1) { // Clear mode does not allow any fancy shading. WRITE(p, " gl_FragColor = v_color0;\n"); } else { const char *secondary = ""; // Secondary color for specular on top of texture if (lmode) { WRITE(p, " vec4 s = vec4(v_color1, 0.0);\n"); secondary = " + s"; } else { secondary = ""; } if (gstate.textureMapEnable & 1) { WRITE(p, " vec4 t = texture2D(tex, v_texcoord);\n"); WRITE(p, " vec4 p = v_color0;\n"); if (gstate.texfunc & 0x100) { // texfmt == RGBA switch (gstate.texfunc & 0x7) { case GE_TEXFUNC_MODULATE: WRITE(p, " vec4 v = t * p%s;\n", secondary); break; case GE_TEXFUNC_DECAL: WRITE(p, " vec4 v = vec4(1.0 - t.a * p.rgb + t.a * u_texenv.rgb, p.a)%s;\n", secondary); break; case GE_TEXFUNC_BLEND: WRITE(p, " vec4 v = vec4((1.0 - t.rgb) * p.rgb + t.rgb * u_texenv.rgb, p.a * t.a)%s;\n", secondary); break; case GE_TEXFUNC_REPLACE: WRITE(p, " vec4 v = t%s;\n", secondary); break; case GE_TEXFUNC_ADD: WRITE(p, " vec4 v = vec4(t.rgb + p.rgb, p.a * t.a)%s;\n", secondary); break; default: WRITE(p, " vec4 v = p;\n"); break; } } else { // texfmt == RGB switch (gstate.texfunc & 0x7) { case GE_TEXFUNC_MODULATE: WRITE(p, " vec4 v = vec4(t.rgb * p.rgb, p.a)%s;\n", secondary); break; case GE_TEXFUNC_DECAL: WRITE(p, " vec4 v = vec4(t.rgb, p.a)%s;\n", secondary); break; case GE_TEXFUNC_BLEND: WRITE(p, " vec4 v = vec4(1.0 - t.rgb) * p.rgb + t.rgb * u_texenv.rgb, p.a)%s;\n", secondary); break; case GE_TEXFUNC_REPLACE: WRITE(p, " vec4 v = vec4(t.rgb, p.a)%s;\n", secondary); break; case GE_TEXFUNC_ADD: WRITE(p, " vec4 v = vec4(t.rgb + p.rgb, p.a)%s;\n", secondary); break; default: WRITE(p, " vec4 v = p;\n"); break; } } } else { // No texture mapping WRITE(p, " vec4 v = v_color0 %s;\n", secondary); } if (enableColorDoubling) { WRITE(p, " v = v * 2.0;\n"); } if (enableAlphaTest) { int alphaTestFunc = gstate.alphatest & 7; const char *alphaTestFuncs[] = { "#", "#", " != ", " == ", " >= ", " > ", " <= ", " < " }; // never/always don't make sense if (alphaTestFuncs[alphaTestFunc][0] != '#') WRITE(p, " if (v.a %s u_alphacolorref.a) discard;\n", alphaTestFuncs[alphaTestFunc]); } // Disabled for now until we actually find a need for it. /* if (enableColorTest) { // TODO: There are some colortestmasks we could handle. int colorTestFunc = gstate.colortest & 3; const char *colorTestFuncs[] = { "#", "#", " == ", " != " }; // never/always don't make sense} int colorTestMask = gstate.colormask; if (colorTestFuncs[colorTestFunc][0] != '#') WRITE(p, "if (!(v.rgb %s (u_alphacolorref.rgb & u_colormask.rgb)) discard;\n", colorTestFuncs[colorTestFunc]); }*/ if (enableFog) { WRITE(p, " float fogCoef = clamp(v_fogdepth, 0.0, 1.0);\n"); WRITE(p, " gl_FragColor = mix(vec4(u_fogcolor, v.a), v, fogCoef);\n"); // WRITE(p, " v.x = v_depth;\n"); } else { WRITE(p, " gl_FragColor = v;\n"); } } #ifdef DEBUG_SHADER if (doTexture) { WRITE(p, " gl_FragColor = texture2D(tex, v_texcoord);\n"); } else { WRITE(p, " gl_FragColor = vec4(1,0,1,1);\n"); } #endif WRITE(p, "}\n"); }