Pica/VertexShader: Fixed LOOP with more than one iteration.

Previously it wouldn't jump back to the start of the loop code once it reached the end of the block.
Fixes the texture problems in a lot of games.
This commit is contained in:
Subv 2015-02-21 12:52:21 -05:00
parent c7d1480ece
commit 9a03e9c61d

View file

@ -90,6 +90,7 @@ struct VertexShaderState {
u8 repeat_counter; // How often to repeat until this call stack element is removed
u8 loop_increment; // Which value to add to the loop counter after an iteration
// TODO: Should this be a signed value? Does it even matter?
u32 loop_address; // The address where we'll return to after each loop iteration
};
// TODO: Is there a maximal size for this?
@ -115,6 +116,8 @@ static void ProcessShaderCode(VertexShaderState& state) {
if (top.repeat_counter-- == 0) {
state.program_counter = &shader_memory[top.return_address];
state.call_stack.pop();
} else {
state.program_counter = &shader_memory[top.loop_address];
}
// TODO: Is "trying again" accurate to hardware?
@ -129,7 +132,7 @@ static void ProcessShaderCode(VertexShaderState& state) {
static auto call = [](VertexShaderState& state, u32 offset, u32 num_instructions,
u32 return_offset, u8 repeat_count, u8 loop_increment) {
state.program_counter = &shader_memory[offset] - 1; // -1 to make sure when incrementing the PC we end up at the correct offset
state.call_stack.push({ offset + num_instructions, return_offset, repeat_count, loop_increment });
state.call_stack.push({ offset + num_instructions, return_offset, repeat_count, loop_increment, offset });
};
u32 binary_offset = state.program_counter - shader_memory.data();