81 lines
2.3 KiB
C++
81 lines
2.3 KiB
C++
#pragma once
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#include <stdint.h>
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#include <algorithm>
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#include "../datatypes.cpp"
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#include "../helpers.cpp"
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#include "../buffer.cpp"
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#include "../shader.cpp"
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namespace UwU {
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// trapezoid (horizontally constrained)
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class Trapezoid {
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public:
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Trapezoid(uint16_t y0, uint16_t y1, uint16_t xl0, uint16_t xl1, uint16_t xr0, uint16_t xr1) {
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this->y0 = y0;
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this->y1 = y1;
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this->xl0 = xl0;
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this->xl1 = xl1;
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this->xr0 = xr0;
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this->xr1 = xr1;
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}
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Trapezoid() {}
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uint16_t y0;
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uint16_t y1;
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uint16_t xl0;
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uint16_t xl1;
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uint16_t xr0;
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uint16_t xr1;
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// Draw a horizontally bounded trapezoid
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// y1 >= y0
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void draw (Buffer buffer, Shader shader) {
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uint16_t height = 1 + y1 - y0;
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int16_t LeftBound[height];
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int16_t RightBound[height];
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Helpers::bresenham(0, xl0, y1 - y0, xl1, LeftBound);
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Helpers::bresenham(0, xr0, y1 - y0, xr1, RightBound);
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if (shader.shaderType == COLOR) {
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for (uint16_t i = 0; i < height; i++) {
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for (uint16_t x = LeftBound[i]; x <= RightBound[i]; x++) {
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buffer.drawPixel(x, i + y0, shader.c0);
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}
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}
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return;
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} else if (shader.shaderType == HGRADIENT) {
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// find left-right boundaries
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uint16_t leftmost = std::min(xl0, xl1);
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uint16_t rightmost = std::max(xr0, xr1);
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// precompute gradient LUT
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Color cols[rightmost - leftmost];
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for (uint16_t x = leftmost; x < rightmost; x++) {
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cols[x - leftmost] = ShaderMethods::gradient(shader.u0, shader.scale, shader.c0, shader.c1, x);
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}
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for (uint16_t i = 0; i < height; i++) {
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for (uint16_t x = LeftBound[i]; x <= RightBound[i]; x++) {
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buffer.drawPixel(x, i + y0, cols[x - leftmost]);
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}
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}
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return;
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} else if (shader.shaderType == VGRADIENT) {
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Color c;
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for (uint16_t i = 0; i < height; i++) {
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c = ShaderMethods::gradient(shader.v0, shader.scale, shader.c0, shader.c1, i + y0);
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for (uint16_t x = LeftBound[i]; x <= RightBound[i]; x++) {
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buffer.drawPixel(x, i + y0, c);
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}
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}
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return;
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}
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return;
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}
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};
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} |