thirdparty/scummvm
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Some more fraction data & an optimized formula (I still have no clue what that tries to compute, though :)

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svn-id: r26043
This commit is contained in:
Max Horn 2007-03-09 22:31:27 +00:00
parent 3b09bc6c00
commit e8e33e8077
1 changed files with 9 additions and 3 deletions
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12
engines/scumm/he/logic_he.cpp
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@ -357,13 +357,12 @@ int32 LogicHErace::op_1140(int32 *args) {
double projX = args[0] - 2 * scalarProduct * args[2]; double projX = args[0] - 2 * scalarProduct * args[2];
double projY = args[1] - 2 * scalarProduct * args[3]; double projY = args[1] - 2 * scalarProduct * args[3];
// 0.86956525 = 1/1.15 = 20/23 = 40/46 projX = projX * 20.0 / 23.0; // FIXME: Why is this here?
projX *= 0.86956525; // FIXME: Why is this here?
writeScummVar(108, (int32)projX); writeScummVar(108, (int32)projX);
if (args[3] >= 0) // FIXME: Why is this here? if (args[3] >= 0) // FIXME: Why is this here?
projY *= 0.83333331f; // FIXME: This value looks like 5/6 projY = projY * 5.0 / 6.0;
writeScummVar(109, (int32)projY); writeScummVar(109, (int32)projY);
@ -684,13 +683,19 @@ int LogicHEfootball::op_1006(int32 *args) {
// 2.9411764e-4 = 1/3400 // 2.9411764e-4 = 1/3400
// 5.3050399e-2 = 1/18.85 = 20/377 // 5.3050399e-2 = 1/18.85 = 20/377
// 1.1764706e-2 = 1/85 = 40/3400 // 1.1764706e-2 = 1/85 = 40/3400
// 1.2360656e-1 = 377/3050
res = (1.0 - a1 * 2.9411764e-4 * 5.3050399e-2) * 1.2360656e-1 * args[0] + res = (1.0 - a1 * 2.9411764e-4 * 5.3050399e-2) * 1.2360656e-1 * args[0] +
a1 * 1.1764706e-2 + 46; a1 * 1.1764706e-2 + 46;
// Shortened / optimized version of that formula:
// res = (377.0 - a1 / 170.0) / 3050.0 * args[0] + a1 / 85.0 + 46;
writeScummVar(108, (int32)res); writeScummVar(108, (int32)res);
// 1.2360656e-1 = 377/3050 // 1.2360656e-1 = 377/3050
// 1.1588235e-1 = 197/1700 = 394/3400 // 1.1588235e-1 = 197/1700 = 394/3400
res = 640.0 - args[2] * 1.2360656e-1 - a1 * 1.1588235e-1 - 26; res = 640.0 - args[2] * 1.2360656e-1 - a1 * 1.1588235e-1 - 26;
writeScummVar(109, (int32)res); writeScummVar(109, (int32)res);
return 1; return 1;
@ -724,6 +729,7 @@ int LogicHEfootball::op_1010(int32 *args) {
// 2.9411764e-4 = 1/3400 // 2.9411764e-4 = 1/3400
// 5.3050399e-2 = 1/18.85 = 20/377 // 5.3050399e-2 = 1/18.85 = 20/377
// 1.1764706e-2 = 1/85 = 40/3400 // 1.1764706e-2 = 1/85 = 40/3400
// 1.2360656e-1 = 377/3050
double a0 = ((double)args[0] - 46 - a1 * 1.1764706e-2) / double a0 = ((double)args[0] - 46 - a1 * 1.1764706e-2) /
((1.0 - a1 * 2.9411764e-4 * 5.3050399e-2) * 1.2360656e-1); ((1.0 - a1 * 2.9411764e-4 * 5.3050399e-2) * 1.2360656e-1);