added mipmaps for the hw renderer, improvementsHEADmain

This commit add mipmaps, but for now, mipmaps are generated on the gpu
at runtime. We should generate them in advance.

- added mipmaps for the hardware renderer
- renamed stb_image.c to stb_image.cpp
- add compiler flag to stb_image.cpp to prevent warning
- added pipe notation for various objects to have all clipping functions
  be left to right. We need this for the time being because dot notation
  would considerably complicate the current implementation
- small improvements

1 files changed, 7 insertions, 22 deletions

diff --git a/src/shaders/simple_shaders.hpp b/src/shaders/simple_shaders.hpp
index c308ab3..831f969 100644
--- a/src/shaders/simple_shaders.hpp
+++ b/src/shaders/simple_shaders.hpp
@@ -3,6 +3,7 @@
 
 #include <algorithm>
 #include <cmath>
+#include <vector>
 #include "fb/pixfb.hpp"
 #include "math/vector.hpp"
 #include "math/mat4.hpp"
@@ -16,7 +17,7 @@ class SimpleShaders {
 
         engine::math::Matrix4 model_mat, view_mat, proj_mat, final_mat;
         int w, h;
-        unsigned char* pixels;
+        std::vector<engine::math::Vector4> pixels;
 
         SimpleShaders(int w, int h, unsigned char* pixels);
         void set_view(const engine::math::Matrix4& view_mat, const engine::math::Matrix4& proj_mat);
@@ -54,27 +55,11 @@ class SimpleShaders {
             int tx1 = std::clamp(static_cast<int>(txf) + 1, 0, w);
             int ty0 = std::clamp(static_cast<int>(tyf) + 0, 0, h);
             int ty1 = std::clamp(static_cast<int>(tyf) + 1, 0, h);
-            float r00 = static_cast<float>(pixels[(tx0 + ty0 * w) * 4 + 0]) / 255.f;
-            float r10 = static_cast<float>(pixels[(tx1 + ty0 * w) * 4 + 0]) / 255.f;
-            float r01 = static_cast<float>(pixels[(tx0 + ty1 * w) * 4 + 0]) / 255.f;
-            float r11 = static_cast<float>(pixels[(tx1 + ty1 * w) * 4 + 0]) / 255.f;
-            float r = (1.f - fac_x) * (1.f - fac_y) * r00 + fac_x * (1.f - fac_y) * r10 + (1.f - fac_x) * fac_y * r01 + fac_x * fac_y * r11;
-            float g00 = static_cast<float>(pixels[(tx0 + ty0 * w) * 4 + 1]) / 255.f;
-            float g10 = static_cast<float>(pixels[(tx1 + ty0 * w) * 4 + 1]) / 255.f;
-            float g01 = static_cast<float>(pixels[(tx0 + ty1 * w) * 4 + 1]) / 255.f;
-            float g11 = static_cast<float>(pixels[(tx1 + ty1 * w) * 4 + 1]) / 255.f;
-            float g = (1.f - fac_x) * (1.f - fac_y) * g00 + fac_x * (1.f - fac_y) * g10 + (1.f - fac_x) * fac_y * g01 + fac_x * fac_y * g11;
-            float b00 = static_cast<float>(pixels[(tx0 + ty0 * w) * 4 + 2]) / 255.f;
-            float b10 = static_cast<float>(pixels[(tx1 + ty0 * w) * 4 + 2]) / 255.f;
-            float b01 = static_cast<float>(pixels[(tx0 + ty1 * w) * 4 + 2]) / 255.f;
-            float b11 = static_cast<float>(pixels[(tx1 + ty1 * w) * 4 + 2]) / 255.f;
-            float b = (1.f - fac_x) * (1.f - fac_y) * b00 + fac_x * (1.f - fac_y) * b10 + (1.f - fac_x) * fac_y * b01 + fac_x * fac_y * b11;
-            float a00 = static_cast<float>(pixels[(tx0 + ty0 * w) * 4 + 3]) / 255.f;
-            float a10 = static_cast<float>(pixels[(tx1 + ty0 * w) * 4 + 3]) / 255.f;
-            float a01 = static_cast<float>(pixels[(tx0 + ty1 * w) * 4 + 3]) / 255.f;
-            float a11 = static_cast<float>(pixels[(tx1 + ty1 * w) * 4 + 3]) / 255.f;
-            float a = (1.f - fac_x) * (1.f - fac_y) * a00 + fac_x * (1.f - fac_y) * a10 + (1.f - fac_x) * fac_y * a01 + fac_x * fac_y * a11;
-            return engine::math::Vector4 { r, g, b, a };
+            return
+                  ((1.f - fac_x) * (1.f - fac_y)) * pixels[tx0 + ty0 * w]
+                + (fac_x         * (1.f - fac_y)) * pixels[tx1 + ty0 * w]
+                + ((1.f - fac_x) * fac_y        ) * pixels[tx0 + ty1 * w]
+                + (fac_x         * fac_y        ) * pixels[tx1 + ty1 * w];
         }
 };